Merge pull request 'Étape 4' (#46) from etape4 into master

Jenkinsfile

@@ -11,6 +11,10 @@
             sh 'echo "BUILDING SERVER"'
             sh 'echo Main-Class: serverP2P/ServerP2P > MANIFEST.MF'
             sh 'jar -cvmf MANIFEST.MF server.jar $(find bin/ -maxdepth 1 -mindepth 1 -printf "-C bin %f\n")'
+            sh 'echo "BUILDING TRACKER"'
+            sh 'echo Main-Class: tracker/Tracker > MANIFEST.MF'
+            sh 'jar -cvmf MANIFEST.MF tracker.jar $(find bin/ -maxdepth 1 -mindepth 1 -printf "-C bin %f\n")'
+            sh 'echo "CREATING sources.tar.gz"'
             sh 'tar -zcvf sources.tar.gz src/'
           }
         }
@@ -24,6 +28,7 @@
         success {
           archiveArtifacts artifacts: 'client.jar', fingerprint: true
           archiveArtifacts artifacts: 'server.jar', fingerprint: true
+          archiveArtifacts artifacts: 'tracker.jar', fingerprint: true
           archiveArtifacts artifacts: 'sources.tar.gz', fingerprint: true
         }
       }

README.md

@@ -6,6 +6,12 @@ Lien vers le [document original](https://stri-online.net/FTLV/mod/resource/view.
 **But** : le but de ce projet est de créer une application répartie en Java de téléchargement de fichier en mode P2P (peer to peer ou poste à poste).
 Les étapes suivantes sont conseillées.
 
+# Usage
+
+tracker : java tracker.Tracker (interactive) or java trackerP2P.trackerP2P -- <hostname> <PORT> (default port 6969 (range 6000 -> 6999))
+server : java serveurP2P.ServeurP2P (interactive) or java serveurP2P.ServeurP2P -- <serveurHOSTNAME> <serveurPORT> <trackerHOSTNAME> <trackerPORT> (default server port: server 7070 (range 7000->7070) and tracker port 6969 (range 7000 -> 7999))
+client/serveur : java clientP2P.ClientP2P or java clientP2P.ClientP2P -- <clientTransportProtocol> <integratedServerHOSTNAME> <integratedServerPORT> <trackerHOSTNAME> <trackerPORT> (default tracker port 6969 (range 7000 -> 7999) and server port: server 7070 (range 7000->7070))
+
 ## Étape 1 : Téléchargement à la FTP
 
 La première étape doit permettre de télécharger un fichier en intégralité d'une machine vers une autre machine de façon similaire aux applications suivant le protocole FTP.
@@ -47,4 +53,4 @@ Options :
 - Permettre la recherche de fichiers à partir de leur nom ou de toute autre caractéristique. À l'issu de la recherche on devra pouvoir connaître un ensemble d'application possédant le fichier et commencer le téléchargement.
 - Gérer le protocole d'une application de téléchargement P2P existante (bittorrent, emule ou autre).
 
-Note : toute fonctionnalité supplémentaire ne sera prise en compte dans la notation que si toutes les étapes ont été correctement traitées.
+Note : toute fonctionnalité supplémentaire ne sera prise en compte dans la notation que si toutes les étapes ont été correctement traitées.

doc/protocol.md

@@ -17,17 +17,22 @@ x bytes: [(bytes 8-?): PAYLOAD]
 	- `LIST` (0x00)
 	- `LOAD` (0x01)
 	- `HASH` (0x02)
+	- `DISCOVER` (0x03)
+	- `REGISTER` (0x04)
+	- `UNREGISTER` (0x05)
 
 - RESPONSES (msb is 1):
 	- `LIST` (0x80)
 	- `LOAD` (0x81)
 	- `HASH` (0x82)
+	- `DISCOVER` (0x83)
 	- `VERSION ERROR` (0xC0)
 	- `PROTOCOL ERROR` (0xC1)
 	- `INTERNAL ERROR` (0xC2)
 	- `EMPTY DIRECTORY` (0xC3)
 	- `NOT FOUND` (0xC4)
 	- `EMPTY FILE` (0xC5)
+	- `NOT A TRACKER` (0xC6)
 
 ### List
 Payload size for list request is always zero.
@@ -97,6 +102,55 @@ A algo hash bloc contains:
 
 ```
 
+### Tracker specific messages
+#### Register
+Used by a server to register itself on a tracker.
+Server may want to do a free `DISCOVER` to check if they have been registered.
+Payload contains:
+
+```
+2 bytes: [<PORT NUMBER>]
+```
+
+#### Unregister
+Used by a server to unregister itself from a tracker.
+No error is raised if the server was not registered.
+Server may want to do a free `DISCOVER` to check if they have been unregistered.
+Payload contains:
+
+```
+2 bytes: [<PORT NUMBER>]
+? bytes: [<HOSTNAME>]
+```
+
+#### Discover request
+If payload size is null, lists all servers registered.
+If payload contains a filename, list all servers having this file in their list.
+
+```
+? bytes: [<FILENAME>]
+? bytes: [<HOSTNAME>]
+```
+
+#### Discover response
+Contains:
+```
+4 bytes: [(bytes  8-11): FILENAME SIZE]
+y bytes: [<FILENAME>]
+? bytes [multiple server blocks] 
+```
+
+Server block is composed with:
+
+```
+2 bytes: [port]
+? bytes: hostname
+\n
+```
+
+#### Not a Tracker
+This error is raised when receiving a DISCOVER, a REGISTER, or an UNREGISTER request,
+but this application is not a tracker.
 
 ### Other response code (errors)
 #### Version error

doc/tracker_sequence_diagram.drawio

@@ -0,0 +1 @@
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src/clientP2P/ClientDownload.java

@@ -0,0 +1,409 @@
+package clientP2P;
+
+import java.util.List;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Random;
+import java.io.IOException;
+import java.io.File;
+import java.nio.file.Files;
+import java.nio.file.StandardOpenOption;
+import java.nio.file.StandardCopyOption;
+import exception.LocalException;
+import exception.RemoteException;
+import localException.SocketClosed;
+import localException.ProtocolError;
+import localException.InternalError;
+import localException.TransmissionError;
+import localException.SizeError;
+import localException.VersionError;
+import remoteException.EmptyDirectory;
+import remoteException.EmptyFile;
+import remoteException.VersionRemoteError;
+import remoteException.ProtocolRemoteError;
+import remoteException.NotFound;
+import remoteException.InternalRemoteError;
+import remoteException.NotATracker;
+import protocolP2P.HashAlgorithm;
+import protocolP2P.HashResponse;
+import protocolP2P.HashRequest;
+import protocolP2P.Payload;
+import protocolP2P.FilePart;
+import protocolP2P.LoadRequest;
+import protocolP2P.ProtocolP2PPacket;
+import clientP2P.ClientDownloadPart;
+import tools.HostItem;
+import tools.Logger;
+import tools.LogLevel;
+import tools.ServeErrors;
+
+/** Class to download file
+* @author	Louis Royer
+* @author	Flavien Haas
+* @author	JS Auge
+* @version	1.0
+*/
+public abstract class ClientDownload extends ServeErrors implements Runnable {
+	protected List<HostItem> hostList;
+	protected String filename;
+	protected byte[] hash512;
+	protected List<ClientDownloadPart> sockList = new ArrayList<ClientDownloadPart>();
+	protected List<Long> offsetsToAsk = new ArrayList<Long>();
+	protected List<Long> offsetsPending = new ArrayList<Long>();
+	protected boolean stop;
+	protected long size;
+	protected static final long MAX_PARTIAL_SIZE = 4096;
+	protected String partsSubdir;
+	protected String dirStorage;
+	protected boolean success = false;
+	protected Logger logger;
+	
+	/** Constructor with parameters: filename, list of hosts, parts subdirectory and dirStorage
+	 * @param filename	name of file to download
+	 * @param hostList	list of servers
+	 * @param partsSubdir	directory to store .part files
+	 * @param dirStorage	directory to write assembled file
+	 * @param logger	Logger
+	 */
+	public ClientDownload(String filename, List<HostItem> hostList, String partsSubdir, String dirStorage, Logger logger) {
+		this.partsSubdir = partsSubdir;
+		this.dirStorage = dirStorage;
+		this.filename = filename;
+		this.hostList = hostList;
+		this.logger = logger;
+		this.stop = false;
+	}
+
+	/** Success getter.
+	 * @return	true when file have successfully been reassembled.
+	 */
+	public boolean getSuccess() {
+		return success;
+	}
+
+	/** Getter for hash512sum
+	 * @return	hash512sum
+	 */
+	public byte[] getHashSum512() {
+		return hash512;
+	}
+
+	/** Stop threads */
+	protected void stopTasks() {
+		for(ClientDownloadPart c : sockList) {
+			try {
+				c.setStop();
+			} catch (InterruptedException e) {
+				writeLog(e, LogLevel.Error);
+			}
+		}
+	}
+
+	/** Asks thread to stop
+	 */
+	public void setStop() {
+		stop = true;
+	}
+
+	/** Assign tasks randomly to threads.
+	 * @throws	InternalError
+	 */
+	protected void assignTasks() throws InternalError {
+		Random rand = new Random();
+		for(long offset : offsetsToAsk) {
+			try {
+				sockList.get(rand.nextInt(sockList.size())).assignTask(offset);
+				offsetsPending.add(offset);
+				System.err.println("Assigned task "+ offset);
+				writeLog("Assigned task "+ offset, LogLevel.Info);
+			} catch(InterruptedException e) {
+				writeLog(e, LogLevel.Error);
+				throw new InternalError();
+			}
+		}
+		offsetsToAsk.removeAll(offsetsPending);
+	}
+
+	/** Create a clientDownloadPart
+	 * @param filename	name of the file to download
+	 * @param hostItem	Hostitem of the server
+	 */
+	protected abstract ClientDownloadPart createDownloadPart(String filename, HostItem hostItem);
+
+	/** Starts threads for each server in hostList.
+	 */
+	protected void initThreads() {
+		for(HostItem hostItem: hostList) {
+			sockList.add(createDownloadPart(filename, hostItem));
+		}
+		for(ClientDownloadPart c: sockList) {
+			Thread t = new Thread(c);
+			t.start();
+		}
+		writeLog("Threads initialized", LogLevel.Info);
+	}
+
+	/** Remove tasks from failed threads. Update done status.
+	 * @throws	InternalError
+	 */
+	protected void checkTasksStatus() throws InternalError {
+		try {
+			synchronized(this) {
+				this.wait();
+				List<ClientDownloadPart> sockListCpy = new ArrayList<>(sockList);
+				for(ClientDownloadPart c: sockListCpy) {
+					if (c.hasFailed() == true) {
+						sockList.remove(c);
+						offsetsPending.removeAll(c.getFailed());
+						offsetsToAsk.addAll(c.getFailed());
+					}
+					try {
+						offsetsPending.removeAll(c.getDone());
+					} catch (InterruptedException e) {
+						throw new InternalError();
+					}
+				}
+				writeLog("Task check status: " + offsetsToAsk.size() + " to asks, " + offsetsPending.size() + " pending", LogLevel.Info);
+				if (offsetsToAsk.isEmpty() && offsetsPending.isEmpty()) {
+					stop = true;
+				}
+				if (sockList.size() == 0) {
+					logger.writeUDP("No thread working", LogLevel.Error);
+					throw new InternalError();
+				}
+			}
+		} catch (InterruptedException e) {
+			throw new InternalError();
+		}
+	}
+
+	/** Get hashsum from server.
+	 * @param hostItem	server to ask hash
+	 * @return	hash512sum
+	 * @throws	InternalError
+	 */
+	protected byte[] getHashSum512(HostItem hostItem) throws InternalError {
+		byte[] hash;
+		HashAlgorithm[] hashesAlgo = new HashAlgorithm[1];
+		hashesAlgo[0] = HashAlgorithm.SHA512;
+		ProtocolP2PPacket<?> d = createProtocolP2PPacket(new HashRequest(filename, hashesAlgo));
+		try {
+			d.sendRequest(getHostItemSocket(hostItem));
+			try {
+				Payload pHash = d.receiveResponse().getPayload();
+				assert pHash instanceof HashResponse : "This payload must be instance of HashResponse";
+				if (!(pHash instanceof HashResponse)) {
+					throw new InternalError();
+				} else {
+					hash = ((HashResponse)pHash).getHash(HashAlgorithm.SHA512);
+				}
+			} catch (EmptyDirectory e) {
+				writeLog(e, LogLevel.Error);
+				hash = new byte[0];
+			} catch (NotFound e) {
+				writeLog(e, LogLevel.Error);
+				hash = new byte[0];
+			} catch (LocalException e) {
+				writeLog(e, LogLevel.Error);
+				throw new InternalError();
+			} catch (RemoteException e) {
+				writeLog(e, LogLevel.Error);
+				throw new InternalError();
+			}
+			return hash;
+		} catch (IOException e) {
+			writeLog(e, LogLevel.Error);
+			throw new InternalError();
+		} catch (SocketClosed e){
+			System.err.println("getHashSum512 : SocketClosed");
+			writeLog("getHashSum512 : SocketClosed", LogLevel.Error);
+			throw new InternalError();
+		}
+	}
+
+	/** Removes servers not owning the correct file to download from list.
+	 * This is done by comparing hash512sum.
+	 * @throws	InternalError
+	 */
+	protected void purgeList() throws InternalError {
+		List<HostItem> blackList = new ArrayList<HostItem>();
+		boolean first = false;
+		byte[] hashsum;
+		for(HostItem host: hostList) {
+			// already have hashsum from 1st server
+			if (!first) {
+				first = true;
+				continue;
+			}
+			// ask hashsum
+			hashsum = getHashSum512(host);
+			if (!Arrays.equals(hash512, hashsum)) {
+				blackList.add(host);
+			}
+		}
+		// purge list
+		for(HostItem host: blackList) {
+			hostList.remove(host);
+		}
+		writeLog("Host list purge: done", LogLevel.Info);
+	}
+
+
+	/** Reassemble file from file parts.
+	 * Set success to true if file is reassembled successfully.
+	 */
+	protected void reassembleFile() {
+		boolean firstPart = true;
+		boolean abort = false;
+		long nextOffset = 0;
+		do {
+			if (firstPart) {
+				writeLog("Reassembling: First part", LogLevel.Info);
+				try {
+					// create file
+					Files.copy(new File(partsSubdir + filename + "_" + nextOffset + ".part").toPath(), new File(dirStorage + filename).toPath(), StandardCopyOption.REPLACE_EXISTING);
+					nextOffset = (new File(dirStorage + filename)).length();
+					firstPart = false;
+				} catch (IOException e) {
+					writeLog("Reassembling: aborting on first part", LogLevel.Warning);
+					abort = true;
+				}
+			} else if (nextOffset >= size) {
+				success = true;
+				writeLog("Reassembling: success", LogLevel.Info);
+			} else {
+				// append to file
+				try {
+					Files.write(new File(dirStorage + filename).toPath(), Files.readAllBytes(new File(partsSubdir + filename + "_" + nextOffset + ".part").toPath()), StandardOpenOption.APPEND);
+					nextOffset = (new File(dirStorage + filename)).length();
+				} catch (IOException e) {
+					abort = true;
+					writeLog("Aborting: bad number " + nextOffset, LogLevel.Error);
+				}
+			}
+		} while((!success) && (!abort));
+	}
+
+
+	/** Set size of file to download. Also download first file part.
+	 * @throws InternalError
+	 */
+	protected void setSize() throws InternalError {
+		ProtocolP2PPacket<?> d = createProtocolP2PPacket(new LoadRequest(filename, 0, MAX_PARTIAL_SIZE));
+		try {
+			d.sendRequest(getHostItemSocket(hostList.get(0)));
+			try {
+				Payload p = d.receiveResponse().getPayload();
+				assert p instanceof FilePart : "This payload must be instance of FilePart";
+				if (!(p instanceof FilePart)) {
+					System.err.println("Error: cannot get size.");
+					writeLog("cannot get size.", LogLevel.Error);
+					throw new InternalError();
+				} else {
+					FilePart fp = (FilePart)p;
+					if (!fp.getFilename().equals(filename)) {
+						System.err.println("Error: wrong file received: `" + fp.getFilename() + "`");
+						writeLog("wrong file received: `" + fp.getFilename() + "`", LogLevel.Error);
+						throw new ProtocolError();
+					}
+					if (fp.getOffset() == 0) {
+						try {
+							Files.write(new File(partsSubdir + filename + "_0.part").toPath(), fp.getPartialContent());
+						} catch (IOException e) {
+							System.err.println("Error: cannot write file (" + partsSubdir + filename + "_0.part)");
+							writeLog("cannot write file (" + partsSubdir + filename + "_0.part)", LogLevel.Error);
+						}
+						size = fp.getTotalSize();
+						if (fp.getPartialContent().length == size) {
+							stop = true;
+						}
+					} else {
+						System.err.println("Error: wrong file part received.");
+						writeLog("wrong file part received.", LogLevel.Error);
+						throw new InternalError();
+					}
+				}
+			} catch (EmptyDirectory e) {
+				System.err.println("Error: empty directory.");
+				writeLog("empty directory.", LogLevel.Error);
+				throw new InternalError();
+			} catch (LocalException e) {
+				writeLog(e, LogLevel.Error);
+				throw new InternalError();
+			} catch (RemoteException e) {
+				writeLog(e, LogLevel.Error);
+				throw new InternalError();
+			}
+		} catch (IOException e) {
+			writeLog(e, LogLevel.Error);
+			throw new InternalError();
+		} catch (SocketClosed e){
+			System.err.println("setSize : SocketClosed");
+			writeLog("setSize : SocketClosed", LogLevel.Error);
+		}
+	}
+
+	/** Close HostItem socket
+	 * @param hostItem	HostItem
+	 */
+	protected abstract void closeHostItemSocket(HostItem hostItem);
+
+
+	/** Runnable implementation
+	 */
+	public void run() {
+		try {
+			init();
+			if (stop) {
+				writeLog("File is smaller than part max size.", LogLevel.Info);
+				closeHostItemSocket(hostList.get(0));
+			} else {
+				writeLog("File is bigger than part max size.", LogLevel.Info);
+				purgeList();
+				initThreads();
+				while(!stop) {
+					assignTasks();
+					checkTasksStatus();
+
+				}
+			}
+			writeLog("Reassembling file parts.", LogLevel.Info);
+			reassembleFile();
+		} catch(InternalError e) {
+			writeLog("Error while downloading file. Aborting.", LogLevel.Error);
+		} finally {
+			stopTasks();
+		}
+	}
+
+	/** Initialize infos about file to download (size, hash512sum, partslist to dl).
+	 * Also download first partfile (to get size).
+	 * @throws	InternalError
+	 */
+	protected void init() throws InternalError {
+		// get size
+		setSize();
+
+		// get hashsum from 1st server in list
+		hash512 = getHashSum512(hostList.get(0));
+		if (hash512.length == 0) {
+			writeLog("no hash512sum support.", LogLevel.Error);
+			throw new InternalError();
+		}
+
+		// Add tasks
+		if (!stop) {
+			for(long i=MAX_PARTIAL_SIZE; i<size;i+=MAX_PARTIAL_SIZE) {
+				offsetsToAsk.add(Long.valueOf(i));
+			}
+			writeLog("Adding tasks: done", LogLevel.Info);
+		}
+	}
+	
+	/** Getter for HostItem socket
+	 * @param hostItem	HostItem
+	 */
+	protected abstract Object getHostItemSocket(HostItem hostItem);
+
+
+}

src/clientP2P/ClientDownloadPart.java

@@ -0,0 +1,310 @@
+package clientP2P;
+import java.util.List;
+import java.util.ArrayList;
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import protocolP2P.ProtocolP2PPacket;
+import protocolP2P.Payload;
+import protocolP2P.LoadRequest;
+import protocolP2P.FilePart;
+import localException.InternalError;
+import localException.ProtocolError;
+import localException.TransmissionError;
+import localException.VersionError;
+import localException.SizeError;
+import localException.SocketClosed;
+import remoteException.EmptyDirectory;
+import remoteException.EmptyFile;
+import remoteException.InternalRemoteError;
+import remoteException.VersionRemoteError;
+import remoteException.ProtocolRemoteError;
+import remoteException.NotFound;
+import remoteException.NotATracker;
+import exception.LocalException;
+import exception.RemoteException;
+import tools.Logger;
+import tools.LogLevel;
+import tools.ServeErrors;
+
+/** Class to download file parts.
+* @author	Louis Royer
+* @author	Flavien Haas
+* @author	JS Auge
+* @version	1.0
+*/
+public abstract class ClientDownloadPart extends ServeErrors implements Runnable {
+	protected List<Long> toDoTasks;
+	protected List<Long> pendingTasks;
+	protected List<Long> tasksDone;
+	protected volatile boolean tasksListsLock;
+	protected volatile boolean stop;
+	protected volatile boolean failed;
+	protected String filename;
+	protected volatile boolean noTask;
+	protected String partsSubdir;
+	protected static final long MAX_PARTIAL_SIZE = 4096;
+	protected ClientDownload manager;
+	protected Logger logger;
+
+	/** Constructor with filename, socket, and part subdir
+	 * @param filename	name of file to download
+	 * @param socket	socket to use
+	 * @param partsSubdir	directory to store .part files
+	 * @param logger	Logger
+	 */
+	public ClientDownloadPart(ClientDownload manager, String filename, String partsSubdir, Logger logger) {
+		this.manager = manager;
+		this.partsSubdir = partsSubdir;
+		this.filename = filename;
+		this.logger = logger;
+		stop = false;
+		failed = false;
+		pendingTasks = new ArrayList<>();
+		toDoTasks = new ArrayList<>();
+		tasksDone = new ArrayList<>();
+		noTask = true;
+		tasksListsLock = false;
+	}
+
+	/** True if thread has failed to get a file.
+	 * @return	true if thread has failed to get a file
+	 */
+	public boolean hasFailed() {
+		return failed;
+	}
+
+	/** Asks to stop thread.
+	 * @throws	InterruptedException
+	 */
+	public synchronized void setStop() throws InterruptedException {
+		stop = true;
+		this.notifyAll();
+	}
+
+	/** Runnable implementation */
+	public void run() {
+		while(!stop) {
+			try {
+				doTasks();
+				synchronized(manager) {
+					manager.notify();
+				}
+			} catch(InterruptedException e) {
+				try {
+					setStop();
+					synchronized(manager) {
+						manager.notify();
+					}
+				} catch (InterruptedException e2) {
+				}
+			}
+		}
+		writeLog("Closing socket", LogLevel.Info);
+		try{
+			closeSocket();
+		} catch(IOException e){
+			writeLog("can't close socket", LogLevel.Error);
+		}
+	}
+
+	/** Close the socket
+	 */
+	protected abstract void closeSocket() throws IOException;
+
+	/** Get list of offsets that have not be downloaded if failed, else
+	 * empty list.
+	 * @return list of offsets
+	 */
+	public List<Long> getFailed() {
+		List<Long> ret = new ArrayList<>();
+		if (failed) {
+			ret.addAll(pendingTasks);
+			ret.addAll(toDoTasks);
+		}
+		return ret;
+	}
+
+	/** Get list of downloaded file parts offset, then clear this list.
+	 * @return	list of offsets
+	 * @throws	InterruptedException
+	 */
+	public List<Long> getDone() throws InterruptedException {
+		if (tasksDone.size() == 0) {
+			return new ArrayList<>();
+		} else {
+			synchronized (this) {
+				while(tasksListsLock) {
+					this.wait();
+				}
+				tasksListsLock = true;
+				List<Long> ret = new ArrayList<>(tasksDone);
+				tasksDone.clear();
+				tasksListsLock = false;
+				this.notifyAll();
+				return ret;
+			}
+		}
+	}
+
+	/** Adds offset of files parts to download.
+	 * @param task	offset to download
+	 * @throws	InterruptedException
+	 */
+	public synchronized void assignTask(Long task) throws InterruptedException {
+		synchronized(this) {
+			while(tasksListsLock) {
+				this.wait();
+			}
+			tasksListsLock = true;
+			toDoTasks.add(task);
+			noTask = false;
+			tasksListsLock = false;
+			this.notifyAll();
+		}
+	}
+
+
+	/** Send one request and wait for one response. Blocks when no task.
+	 * @throws InterruptedException
+	 */
+	public synchronized void doTasks() throws InterruptedException {
+		while(noTask && !stop) {
+			this.wait();
+		}
+		if (!stop) {
+			try {
+				Long offset = toDoTasks.get(0);
+				ProtocolP2PPacket<?> p = reqPart(offset);
+				if (p == null) {
+					stop = true;
+				}
+
+				failed = downloadPart(p);
+				if (failed) {
+					System.err.println("Error: DownloadPart failed.");
+					writeLog("DownloadPart failed.", LogLevel.Error);
+					stop = true;
+				} else if (toDoTasks.isEmpty()) {
+						noTask = true;
+				}
+			} catch (IndexOutOfBoundsException e) {
+				writeLog(e, LogLevel.Error);
+				noTask = true;
+			}
+		}
+	}
+
+	/** Send a request for a specific offset.
+	 * @param offset	Offset of the file part to download
+	 * @return	ProtocolP2PPacketTCP used to send request
+	 */
+	protected ProtocolP2PPacket<?> reqPart(Long offset) {
+		writeLog("New request: " + offset, LogLevel.Info);
+		// maintain tracking of tasks
+		if (toDoTasks.contains(offset)) {
+			try {
+				synchronized (this) {
+					while(tasksListsLock) {
+						this.wait();
+					}
+					tasksListsLock = true;
+					toDoTasks.remove(offset);
+					pendingTasks.add(offset);
+					tasksListsLock = false;
+					this.notifyAll();
+				}
+			} catch(InterruptedException e) {
+				writeLog("reqPart interruptedException", LogLevel.Error);
+				return null;
+			}
+		} else {
+			writeLog("reqPart (offset " + offset + " not in toDoTasks)", LogLevel.Error);
+			return null;
+		}
+		// send request
+		try {
+			ProtocolP2PPacket<?> d = createProtocolP2PPacket(new LoadRequest(filename, offset.longValue(), MAX_PARTIAL_SIZE));
+			d.sendRequest(getSocket());
+			return d;
+		} catch (InternalError e) {
+			writeLog("reqPart internalError", LogLevel.Error);
+			return null;
+		} catch (IOException e) {
+			writeLog("reqPart ioexception", LogLevel.Error);
+			writeLog(e, LogLevel.Error);
+			return null;
+		} catch (SocketClosed e){
+			writeLog("reqPart SocketClosed", LogLevel.Error);
+			return null;
+		}
+	}
+
+	/** Get the socket */
+	protected abstract Object getSocket();
+
+
+	/** Download file part associated to the request send (d).
+	 * @param d	request packet
+	 * @return	true on failure, else false
+	 */
+	public < T extends ProtocolP2PPacket<?> > boolean downloadPart(T d) {
+		if (d == null) {
+			writeLog("downloadPart -> d is null.", LogLevel.Error);
+			return true;
+		}
+		try {
+			Payload p = d.receiveResponse().getPayload();
+			assert p instanceof FilePart : "This payload must be instance of FilePart";
+			if (!(p instanceof FilePart)) {
+				writeLog("cannot get size.", LogLevel.Error);
+				return true;
+			} else {
+				FilePart fp = (FilePart)p;
+				if (!fp.getFilename().equals(filename)) {
+					writeLog("wrong file received: `" + fp.getFilename() + "`", LogLevel.Error);
+					return true;
+				}
+				Long offset = Long.valueOf(fp.getOffset());
+				if (pendingTasks.contains(offset)) {
+					try {
+						Files.write(new File(partsSubdir + filename + "_" + offset + ".part").toPath(), fp.getPartialContent());
+					} catch (IOException e) {
+						writeLog("cannot write file (" + partsSubdir + filename + "_" + offset + ".part)", LogLevel.Error);
+					}
+				} else {
+					writeLog("wrong file part received.", LogLevel.Error);
+					return true;
+				}
+				try {
+					synchronized(this) {
+						while(tasksListsLock) {
+							this.wait();
+						}
+						tasksListsLock = true;
+						pendingTasks.remove(offset);
+						tasksDone.add(offset);
+						tasksListsLock = false;
+						this.notifyAll();
+					}
+				} catch(InterruptedException e) {
+					writeLog("DownloadPart Interrupted exception", LogLevel.Error);
+					return true;
+				}
+			}
+		} catch (LocalException e) {
+			writeLog(e, LogLevel.Error);
+			return true;
+		} catch (RemoteException e) {
+			writeLog(e, LogLevel.Error);
+			return true;
+		} catch (IOException e) {
+			System.err.println("Error: downloadPart ioexception");
+			writeLog("downloadPart ioexception", LogLevel.Error);
+			return true;
+		}
+		return false;
+	}
+
+
+}

src/clientP2P/ClientDownloadPartTCP.java

@@ -2,26 +2,30 @@ package clientP2P;
 import java.util.List;
 import java.util.ArrayList;
 import java.net.Socket;
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
 import protocolP2P.ProtocolP2PPacketTCP;
+import protocolP2P.ProtocolP2PPacket;
 import protocolP2P.Payload;
 import protocolP2P.LoadRequest;
 import protocolP2P.FilePart;
-import exception.InternalError;
+import localException.InternalError;
+import localException.ProtocolError;
+import localException.TransmissionError;
+import localException.VersionError;
+import localException.SizeError;
+import localException.SocketClosed;
 import remoteException.EmptyDirectory;
 import remoteException.EmptyFile;
-import exception.ProtocolError;
 import remoteException.InternalRemoteError;
 import remoteException.VersionRemoteError;
-import exception.TransmissionError;
 import remoteException.ProtocolRemoteError;
-import exception.VersionError;
-import exception.SizeError;
 import remoteException.NotFound;
-import java.nio.file.Files;
-import java.io.File;
-import java.nio.file.Paths;
-import java.io.IOException;
-import exception.SocketClosed;
+import remoteException.NotATracker;
+import tools.Logger;
+import tools.LogLevel;
+import clientP2P.ClientDownloadPart;
 
 /** Class to download file parts on tcp.
 * @author	Louis Royer
@@ -29,297 +33,55 @@ import exception.SocketClosed;
 * @author	JS Auge
 * @version	1.0
 */
-public class ClientDownloadPartTCP implements Runnable {
+public class ClientDownloadPartTCP extends ClientDownloadPart {
 
-	private List<Long> toDoTasks;
-	private List<Long> pendingTasks;
-	private List<Long> tasksDone;
-	private volatile boolean tasksListsLock;
-	private volatile boolean stop;
-	private volatile boolean failed;
-	private String filename;
 	private Socket socket;
-	private volatile boolean noTask;
-	private String partsSubdir;
-	private static final long MAX_PARTIAL_SIZE = 4096;
-	private ClientDownloadTCP manager;
 
 	/** Constructor with filename, socket, and part subdir
 	 * @param filename	name of file to download
 	 * @param socket	socket to use
 	 * @param partsSubdir	directory to store .part files
+	 * @param logger	Logger
 	 */
-	public ClientDownloadPartTCP(ClientDownloadTCP manager, String filename, Socket socket, String partsSubdir) {
-		this.manager = manager;
-		this.partsSubdir = partsSubdir;
-		this.filename = filename;
+	public ClientDownloadPartTCP(ClientDownload manager, String filename, Socket socket, String partsSubdir, Logger logger) {
+		super(manager, filename, partsSubdir, logger);
 		this.socket = socket;
-		stop = false;
-		failed = false;
-		pendingTasks = new ArrayList<>();
-		toDoTasks = new ArrayList<>();
-		tasksDone = new ArrayList<>();
-		noTask = true;
-		tasksListsLock = false;
-	}
-
-	/** True if thread has failed to get a file.
-	 * @return	true if thread has failed to get a file
-	 */
-	public boolean hasFailed() {
-		return failed;
-	}
-
-	/** Asks to stop thread.
-	 * @throws	InterruptedException
-	 */
-	public synchronized void setStop() throws InterruptedException {
-		stop = true;
-		this.notifyAll();
 	}
 
-	/** Runnable implementation */
-	public void run() {
-		while(!stop) {
-			try {
-				doTasks();
-				synchronized(manager) {
-					manager.notify();
-				}
-			} catch(InterruptedException e) {
-				try {
-					setStop();
-					synchronized(manager) {
-						manager.notify();
-					}
-				} catch (InterruptedException e2) {
-				}
-			}
-		}
-		System.err.println("Closing socket");
-		try{
-			socket.close();
-		} catch(IOException e){
-			System.err.println("can't close socket");
-		}
-	}
 
-	/** Get list of offsets that have not be downloaded if failed, else
-	 * empty list.
-	 * @return list of offsets
-	 */
-	public List<Long> getFailed() {
-		List<Long> ret = new ArrayList<>();
-		if (failed) {
-			ret.addAll(pendingTasks);
-			ret.addAll(toDoTasks);
-		}
-		return ret;
+	
+	/** Get the socket */
+	protected Object getSocket() {
+		return (Object) socket;
 	}
-
-	/** Get list of downloaded file parts offset, then clear this list.
-	 * @return	list of offsets
-	 * @throws	InterruptedException
+	
+	/** Close the socket
 	 */
-	public List<Long> getDone() throws InterruptedException {
-		if (tasksDone.size() == 0) {
-			return new ArrayList<>();
-		} else {
-			synchronized (this) {
-				while(tasksListsLock) {
-					this.wait();
-				}
-				tasksListsLock = true;
-				List<Long> ret = new ArrayList<>(tasksDone);
-				tasksDone.clear();
-				tasksListsLock = false;
-				this.notifyAll();
-				return ret;
-			}
-		}
+	protected void closeSocket() throws IOException {
+		socket.close();
 	}
 
-	/** Adds offset of files parts to download.
-	 * @param task	offset to download
-	 * @throws	InterruptedException
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
 	 */
-	public synchronized void assignTask(Long task) throws InterruptedException {
-		synchronized(this) {
-			while(tasksListsLock) {
-				this.wait();
-			}
-			tasksListsLock = true;
-			toDoTasks.add(task);
-			noTask = false;
-			tasksListsLock = false;
-			this.notifyAll();
-		}
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeTCP(text, logLevel);
 	}
 
-	/** Send one request and wait for one response. Blocks when no task.
-	 * @throws InterruptedException
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
 	 */
-	public synchronized void doTasks() throws InterruptedException {
-		while(noTask && !stop) {
-			this.wait();
-		}
-		if (!stop) {
-			try {
-				Long offset = toDoTasks.get(0);
-				ProtocolP2PPacketTCP p = reqPart(offset);
-				if (p == null) {
-					stop = true;
-				}
-
-				failed = downloadPart(p);
-				if (failed) {
-					System.err.println("Error: DownloadPart failed.");
-					stop = true;
-				} else if (toDoTasks.isEmpty()) {
-						noTask = true;
-				}
-			} catch (IndexOutOfBoundsException e) {
-				noTask = true;
-			}
-
-		}
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeTCP(e, logLevel);
 	}
 
-	/** Send a request for a specific offset.
-	 * @param offset	Offset of the file part to download
-	 * @return	ProtocolP2PPacketTCP used to send request
-	 */
-	private ProtocolP2PPacketTCP reqPart(Long offset) {
-		System.err.println("New request: "+ offset);
-		// maintain tracking of tasks
-		if (toDoTasks.contains(offset)) {
-			try {
-				synchronized (this) {
-					while(tasksListsLock) {
-						this.wait();
-					}
-					tasksListsLock = true;
-					toDoTasks.remove(offset);
-					pendingTasks.add(offset);
-					tasksListsLock = false;
-					this.notifyAll();
-				}
-			} catch(InterruptedException e) {
-				System.err.println("Error: reqPart interruptedException");
-				return null;
-			}
-		} else {
-			System.err.println("Error: reqPart (offset " + offset + " not in toDoTasks)");
-			return null;
-		}
-		// send request
-		try {
-			ProtocolP2PPacketTCP d = new ProtocolP2PPacketTCP((Payload) new LoadRequest(filename, offset.longValue(), MAX_PARTIAL_SIZE));
-			d.sendRequest((Object)socket);
-			return d;
-		} catch (InternalError e) {
-			System.err.println("Error: reqPart internalError");
-			return null;
-		} catch (IOException e) {
-			e.printStackTrace();
-			System.err.println("Error: reqPart ioexception");
-			return null;
-		} catch (SocketClosed e){
-			System.err.println("Error: reqPart SocketClosed");
-			return null;
-		}
-	}
 
-	/** Download file part associated to the request send (d).
-	 * @param d	request packet
-	 * @return	true on failure, else false
+	/** Create packets
+	 * @param payload	Payload
 	 */
-	public boolean downloadPart(ProtocolP2PPacketTCP d) {
-		if (d == null) {
-			System.err.println("Error: downloadPart -> d is null.");
-			return true;
-		}
-		try {
-			Payload p = d.receiveResponse().getPayload();
-			assert p instanceof FilePart : "This payload must be instance of FilePart";
-			if (!(p instanceof FilePart)) {
-				System.err.println("Error: cannot get size.");
-				return true;
-			} else {
-				FilePart fp = (FilePart)p;
-				if (!fp.getFilename().equals(filename)) {
-					System.err.println("Error: wrong file received: `" + fp.getFilename() + "`");
-					return true;
-				}
-				Long offset = Long.valueOf(fp.getOffset());
-				if (pendingTasks.contains(offset)) {
-					try {
-						Files.write(new File(partsSubdir + filename + "_" + offset + ".part").toPath(), fp.getPartialContent());
-					} catch (IOException e) {
-						System.err.println("Error: cannot write file (" + partsSubdir + filename + "_" + offset + ".part)");
-					}
-				} else {
-					System.err.println("Error: wrong file part received.");
-					return true;
-				}
-				try {
-					synchronized(this) {
-						while(tasksListsLock) {
-							this.wait();
-						}
-						tasksListsLock = true;
-						pendingTasks.remove(offset);
-						tasksDone.add(offset);
-						tasksListsLock = false;
-						this.notifyAll();
-					}
-				} catch(InterruptedException e) {
-					System.err.println("Error: DownloadPart Interrupted exception");
-					return true;
-				}
-			}
-		} catch (EmptyDirectory e) {
-			System.err.println("Error: empty directory.");
-			return true;
-		} catch (EmptyFile e) {
-			System.err.println("Error: downloadPart emptyFile");
-			// TODO: use more specific errors
-			return true;
-		} catch (ProtocolError e) {
-			System.err.println("Error: downloadPart protocolError");
-			return true;
-		} catch (InternalRemoteError e) {
-			System.err.println("Error: downloadPart internalRemoteError");
-			return true;
-		} catch (VersionRemoteError e) {
-			System.err.println("Error: downloadPart versionRemoteError");
-			return true;
-		} catch (ProtocolRemoteError e) {
-			System.err.println("Error: downloadPart protocolRemoteError");
-			return true;
-		} catch (TransmissionError e) {
-			System.err.println("Error: downloadPart transmissionError");
-			return true;
-		} catch (VersionError e) {
-			System.err.println("Error: downloadPart versionError");
-			return true;
-		} catch (SizeError e) {
-			System.err.println("Error: downloadPart sizeError");
-			return true;
-		} catch (NotFound e) {
-			System.err.println("Error: downloadPart notFound");
-			return true;
-		} catch (IOException e) {
-			System.err.println("Error: downloadPart ioexception");
-			return true;
-		} catch (InternalError e) {
-			System.err.println("Error: downloadPart internalError");
-			return true;
-		} catch (SocketClosed e){
-			System.err.println("Error: downloadPart SocketClosed");
-			return true;
-		}
-		return false;
+	protected < T extends Payload > ProtocolP2PPacket<T> createProtocolP2PPacket(T payload) {
+		return (ProtocolP2PPacket<T>)new ProtocolP2PPacketTCP<T>(payload);
 	}
-
 }

src/clientP2P/ClientDownloadPartUDP.java

@@ -3,24 +3,28 @@ import java.util.List;
 import java.util.ArrayList;
 import java.net.DatagramSocket;
 import protocolP2P.ProtocolP2PPacketUDP;
+import protocolP2P.ProtocolP2PPacket;
 import protocolP2P.Payload;
 import protocolP2P.LoadRequest;
 import protocolP2P.FilePart;
-import exception.InternalError;
+import localException.InternalError;
 import remoteException.EmptyDirectory;
 import remoteException.EmptyFile;
-import exception.ProtocolError;
+import localException.ProtocolError;
 import remoteException.InternalRemoteError;
 import remoteException.VersionRemoteError;
-import exception.TransmissionError;
+import localException.TransmissionError;
 import remoteException.ProtocolRemoteError;
-import exception.VersionError;
-import exception.SizeError;
+import localException.VersionError;
+import localException.SizeError;
 import remoteException.NotFound;
+import remoteException.NotATracker;
 import java.nio.file.Files;
 import java.io.File;
-import java.nio.file.Paths;
 import java.io.IOException;
+import tools.Logger;
+import tools.LogLevel;
+import clientP2P.ClientDownloadPart;
 
 /** Class to download file parts on udp.
 * @author	Louis Royer
@@ -28,287 +32,54 @@ import java.io.IOException;
 * @author	JS Auge
 * @version	1.0
 */
-public class ClientDownloadPartUDP implements Runnable {
+public class ClientDownloadPartUDP extends ClientDownloadPart {
 
-	private List<Long> toDoTasks;
-	private List<Long> pendingTasks;
-	private List<Long> tasksDone;
-	private volatile boolean tasksListsLock;
-	private volatile boolean stop;
-	private volatile boolean failed;
-	private String filename;
 	private DatagramSocket socket;
-	private volatile boolean noTask;
-	private String partsSubdir;
-	private static final long MAX_PARTIAL_SIZE = 4096;
-	private ClientDownloadUDP manager;
+
 
 	/** Constructor with filename, socket, and part subdir
 	 * @param filename	name of file to download
 	 * @param socket	socket to use
 	 * @param partsSubdir	directory to store .part files
+	 * @param logger	Logger
 	 */
-	public ClientDownloadPartUDP(ClientDownloadUDP manager, String filename, DatagramSocket socket, String partsSubdir) {
-		this.manager = manager;
-		this.partsSubdir = partsSubdir;
-		this.filename = filename;
+	public ClientDownloadPartUDP(ClientDownload manager, String filename, DatagramSocket socket, String partsSubdir, Logger logger) {
+		super(manager, filename, partsSubdir, logger);
 		this.socket = socket;
-		stop = false;
-		failed = false;
-		pendingTasks = new ArrayList<>();
-		toDoTasks = new ArrayList<>();
-		tasksDone = new ArrayList<>();
-		noTask = true;
-		tasksListsLock = false;
 	}
 
-	/** True if thread has failed to get a file.
-	 * @return	true if thread has failed to get a file
-	 */
-	public boolean hasFailed() {
-		return failed;
+	/** Get the socket */
+	protected Object getSocket() {
+		return (Object) socket;
 	}
-
-	/** Asks to stop thread.
-	 * @throws	InterruptedException
+	
+	/** Close the socket
 	 */
-	public synchronized void setStop() throws InterruptedException {
-		stop = true;
-		this.notifyAll();
-	}
-
-	/** Runnable implementation */
-	public void run() {
-		while(!stop) {
-			try {
-				doTasks();
-				synchronized(manager) {
-					manager.notify();
-				}
-			} catch(InterruptedException e) {
-				try {
-					setStop();
-					synchronized(manager) {
-						manager.notify();
-					}
-				} catch (InterruptedException e2) {
-				}
-			}
-		}
-		System.err.println("Closing socket");
+	protected void closeSocket() throws IOException {
 		socket.close();
 	}
 
-	/** Get list of offsets that have not be downloaded if failed, else
-	 * empty list.
-	 * @return list of offsets
-	 */
-	public List<Long> getFailed() {
-		List<Long> ret = new ArrayList<>();
-		if (failed) {
-			ret.addAll(pendingTasks);
-			ret.addAll(toDoTasks);
-		}
-		return ret;
-	}
-
-	/** Get list of downloaded file parts offset, then clear this list.
-	 * @return	list of offsets
-	 * @throws	InterruptedException
-	 */
-	public List<Long> getDone() throws InterruptedException {
-		if (tasksDone.size() == 0) {
-			return new ArrayList<>();
-		} else {
-			synchronized (this) {
-				while(tasksListsLock) {
-					this.wait();
-				}
-				tasksListsLock = true;
-				List<Long> ret = new ArrayList<>(tasksDone);
-				tasksDone.clear();
-				tasksListsLock = false;
-				this.notifyAll();
-				return ret;
-			}
-		}
-	}
 
-	/** Adds offset of files parts to download.
-	 * @param task	offset to download
-	 * @throws	InterruptedException
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
 	 */
-	public synchronized void assignTask(Long task) throws InterruptedException {
-		synchronized(this) {
-			while(tasksListsLock) {
-				this.wait();
-			}
-			tasksListsLock = true;
-			toDoTasks.add(task);
-			noTask = false;
-			tasksListsLock = false;
-			this.notifyAll();
-		}
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeUDP(text, logLevel);
 	}
 
-	/** Send one request and wait for one response. Blocks when no task.
-	 * @throws InterruptedException
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
 	 */
-	public synchronized void doTasks() throws InterruptedException {
-		while(noTask && !stop) {
-			this.wait();
-		}
-		if (!stop) {
-			try {
-				Long offset = toDoTasks.get(0);
-				ProtocolP2PPacketUDP p = reqPart(offset);
-				if (p == null) {
-					stop = true;
-				}
-				
-				failed = downloadPart(p);
-				if (failed) {
-					System.err.println("Error: DownloadPart failed.");
-					stop = true;
-				} else if (toDoTasks.isEmpty()) {
-						noTask = true;
-				}
-			} catch (IndexOutOfBoundsException e) {
-				noTask = true;
-			}
-			
-		}
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeUDP(e, logLevel);
 	}
 
-	/** Send a request for a specific offset.
-	 * @param offset	Offset of the file part to download
-	 * @return	ProtocolP2PPacketTCP used to send request
+	/** Create packets
+	 * @param payload	Payload
 	 */
-	private ProtocolP2PPacketUDP reqPart(Long offset) {
-		System.err.println("New request: "+ offset);
-		// maintain tracking of tasks
-		if (toDoTasks.contains(offset)) {
-			try {
-				synchronized (this) {
-					while(tasksListsLock) {
-						this.wait();
-					}
-					tasksListsLock = true;
-					toDoTasks.remove(offset);
-					pendingTasks.add(offset);
-					tasksListsLock = false;
-					this.notifyAll();
-				}
-			} catch(InterruptedException e) {
-				System.err.println("Error: reqPart interruptedException");
-				return null;
-			}
-		} else {
-			System.err.println("Error: reqPart (offset " + offset + " not in toDoTasks)");
-			return null;
-		}
-		// send request
-		try {
-			ProtocolP2PPacketUDP d = new ProtocolP2PPacketUDP((Payload) new LoadRequest(filename, offset.longValue(), MAX_PARTIAL_SIZE));
-			d.sendRequest((Object)socket);
-			return d;
-		} catch (InternalError e) {
-			System.err.println("Error: reqPart internalError");
-			return null;
-		} catch (IOException e) {
-			e.printStackTrace();
-			System.err.println("Error: reqPart ioexception");
-			return null;
-		}
+	protected < T extends Payload > ProtocolP2PPacket<T> createProtocolP2PPacket(T payload) {
+		return (ProtocolP2PPacket<T>)new ProtocolP2PPacketUDP<T>(payload);
 	}
-
-	/** Download file part associated to the request send (d).
-	 * @param d	request packet
-	 * @return	true on failure, else false
-	 */
-	public boolean downloadPart(ProtocolP2PPacketUDP d) {
-		if (d == null) {
-			System.err.println("Error: downloadPart -> d is null.");
-			return true;
-		}
-		try {
-			Payload p = d.receiveResponse().getPayload();
-			assert p instanceof FilePart : "This payload must be instance of FilePart";
-			if (!(p instanceof FilePart)) {
-				System.err.println("Error: cannot get size.");
-				return true;
-			} else {
-				FilePart fp = (FilePart)p;
-				if (!fp.getFilename().equals(filename)) {
-					System.err.println("Error: wrong file received: `" + fp.getFilename() + "`");
-					return true;
-				}
-				Long offset = Long.valueOf(fp.getOffset());
-				if (pendingTasks.contains(offset)) {
-					try {
-						Files.write(new File(partsSubdir + filename + "_" + offset + ".part").toPath(), fp.getPartialContent());
-					} catch (IOException e) {
-						System.err.println("Error: cannot write file (" + partsSubdir + filename + "_" + offset + ".part)");
-					}
-				} else {
-					System.err.println("Error: wrong file part received.");
-					return true;
-				}
-				try {
-					synchronized(this) {
-						while(tasksListsLock) {
-							this.wait();
-						}
-						tasksListsLock = true;
-						pendingTasks.remove(offset);
-						tasksDone.add(offset);
-						tasksListsLock = false;
-						this.notifyAll();
-					}
-				} catch(InterruptedException e) {
-					System.err.println("Error: DownloadPart Interrupted exception");
-					return true;
-				}
-			}
-		} catch (EmptyDirectory e) {
-			System.err.println("Error: empty directory.");
-			return true;
-		} catch (EmptyFile e) {
-			System.err.println("Error: downloadPart emptyFile");
-			// TODO: use more specific errors
-			return true;
-		} catch (ProtocolError e) {
-			System.err.println("Error: downloadPart protocolError");
-			return true;
-		} catch (InternalRemoteError e) {
-			System.err.println("Error: downloadPart internalRemoteError");
-			return true;
-		} catch (VersionRemoteError e) {
-			System.err.println("Error: downloadPart versionRemoteError");
-			return true;
-		} catch (ProtocolRemoteError e) {
-			System.err.println("Error: downloadPart protocolRemoteError");
-			return true;
-		} catch (TransmissionError e) {
-			System.err.println("Error: downloadPart transmissionError");
-			return true;
-		} catch (VersionError e) {
-			System.err.println("Error: downloadPart versionError");
-			return true;
-		} catch (SizeError e) {
-			System.err.println("Error: downloadPart sizeError");
-			return true;
-		} catch (NotFound e) {
-			System.err.println("Error: downloadPart notFound");
-			return true;
-		} catch (IOException e) {
-			System.err.println("Error: downloadPart ioexception");
-			return true;
-		} catch (InternalError e) {
-			System.err.println("Error: downloadPart internalError");
-			return true;
-		}
-		return false;
-	}
-
 }

src/clientP2P/ClientDownloadTCP.java

@@ -1,35 +1,40 @@
 package clientP2P;
-import clientP2P.ClientDownloadPartTCP;
-import tools.HostItem;
+
 import java.util.List;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Random;
+import java.io.IOException;
+import java.io.File;
+import java.nio.file.Files;
+import java.nio.file.StandardOpenOption;
+import java.nio.file.StandardCopyOption;
 import remoteException.EmptyDirectory;
 import remoteException.EmptyFile;
 import remoteException.VersionRemoteError;
 import remoteException.ProtocolRemoteError;
 import remoteException.NotFound;
 import remoteException.InternalRemoteError;
+import remoteException.NotATracker;
+import localException.ProtocolError;
+import localException.InternalError;
+import localException.TransmissionError;
+import localException.SizeError;
+import localException.VersionError;
+import localException.SocketClosed;
 import protocolP2P.HashAlgorithm;
 import protocolP2P.HashResponse;
 import protocolP2P.HashRequest;
 import protocolP2P.ProtocolP2PPacketTCP;
+import protocolP2P.ProtocolP2PPacket;
 import protocolP2P.Payload;
-import exception.ProtocolError;
-import exception.InternalError;
-import exception.TransmissionError;
-import exception.SizeError;
-import exception.VersionError;
 import protocolP2P.FilePart;
 import protocolP2P.LoadRequest;
-import java.io.IOException;
-import java.nio.file.Files;
-import java.io.File;
-import java.nio.file.Paths;
-import java.nio.file.StandardOpenOption;
-import java.nio.file.StandardCopyOption;
-import exception.SocketClosed;
+import clientP2P.ClientDownloadPartTCP;
+import clientP2P.ClientDownload;
+import tools.HostItem;
+import tools.Logger;
+import tools.LogLevel;
 
 /** Class to download file from tcp
 * @author	Louis Royer
@@ -37,353 +42,61 @@ import exception.SocketClosed;
 * @author	JS Auge
 * @version	1.0
 */
-public class ClientDownloadTCP implements Runnable {
-
-	private List<HostItem> hostList;
-	private String filename;
-	private byte[] hash512;
-	private List<ClientDownloadPartTCP> sockList = new ArrayList<ClientDownloadPartTCP>();
-	private List<Long> offsetsToAsk = new ArrayList<Long>();
-	private List<Long> offsetsPending = new ArrayList<Long>();
-	private boolean stop;
-	private long size;
-	private static final long MAX_PARTIAL_SIZE = 4096;
-	private String partsSubdir;
-	private String dirStorage;
-	private boolean success = false;
+public class ClientDownloadTCP extends ClientDownload {
 
 	/** Constructor with parameters: filename, list of hosts, parts subdirectory and dirStorage
 	 * @param filename	name of file to download
 	 * @param hostList	list of servers
 	 * @param partsSubdir	directory to store .part files
 	 * @param dirStorage	directory to write assembled file
+	 * @param logger	Logger
 	 */
-	public ClientDownloadTCP(String filename, List<HostItem> hostList, String partsSubdir, String dirStorage) {
-		this.partsSubdir = partsSubdir;
-		this.dirStorage = dirStorage;
-		this.filename = filename;
-		this.hostList = hostList;
-		this.stop = false;
-	}
-
-	/** Asks thread to stop
-	 */
-	public void setStop() {
-		stop = true;
-	}
-
-	/** Runnable implementation
-	 */
-	public void run() {
-		try {
-			init();
-			if (stop) {
-				System.err.println("File is smaller than part max size.");
-				hostList.get(0).closeTCPSocket();
-			} else {
-				System.err.println("File is bigger than part max size.");
-				purgeList();
-				initThreads();
-				while(!stop) {
-					assignTasks();
-					checkTasksStatus();
-
-				}
-			}
-			System.err.println("Reassembling file parts.");
-			reassembleFile();
-		} catch(InternalError e) {
-			System.err.println("Error while downloading file. Aborting.");
-		} finally {
-			stopTasks();
-		}
-	}
-
-	/** Starts threads for each server in hostList.
-	 */
-	private void initThreads() {
-		for(HostItem hostItem: hostList) {
-			sockList.add(new ClientDownloadPartTCP(this, filename, hostItem.getTCPSocket(), partsSubdir));
-		}
-		for(ClientDownloadPartTCP c: sockList) {
-			Thread t = new Thread(c);
-			t.start();
-		}
-		System.err.println("Threads initialized");
-	}
-
-	/** Remove tasks from failed threads. Update done status.
-	 * @throws	InternalError
-	 */
-	private void checkTasksStatus() throws InternalError {
-		try {
-			synchronized(this) {
-				this.wait();
-				List<ClientDownloadPartTCP> sockListCpy = new ArrayList<>(sockList);
-				for(ClientDownloadPartTCP c: sockListCpy) {
-					if (c.hasFailed() == true) {
-						sockList.remove(c);
-						offsetsPending.removeAll(c.getFailed());
-						offsetsToAsk.addAll(c.getFailed());
-					}
-					try {
-						offsetsPending.removeAll(c.getDone());
-					} catch (InterruptedException e) {
-						throw new InternalError();
-					}
-				}
-				System.err.println("Task check status: " + offsetsToAsk.size() + " to asks, " + offsetsPending.size() + " pending");
-				if (offsetsToAsk.isEmpty() && offsetsPending.isEmpty()) {
-					stop = true;
-				}
-				if (sockList.size() == 0) {
-					System.err.println("No thread working");
-					throw new InternalError();
-				}
-			}
-		} catch (InterruptedException e) {
-			throw new InternalError();
-		}
-	}
-
-	/** Assign tasks randomly to threads.
-	 * @throws	InternalError
-	 */
-	private void assignTasks() throws InternalError {
-		Random rand = new Random();
-		for(long offset : offsetsToAsk) {
-			try {
-				sockList.get(rand.nextInt(sockList.size())).assignTask(offset);
-				offsetsPending.add(offset);
-				System.err.println("Assigned task "+ offset);
-			} catch(InterruptedException e) {
-				throw new InternalError();
-			}
-		}
-		offsetsToAsk.removeAll(offsetsPending);
-	}
-
-	/** Stop threads */
-	private void stopTasks() {
-		for(ClientDownloadPartTCP c : sockList) {
-			try {
-				c.setStop();
-			} catch (InterruptedException e) {}
-		}
-	}
-
-	/** Get hashsum from server.
-	 * @param hostItem	server to ask hash
-	 * @return	hash512sum
-	 * @throws	InternalError
-	 */
-	private byte[] getHashSum512(HostItem hostItem) throws InternalError {
-		byte[] hash;
-		HashAlgorithm[] hashesAlgo = new HashAlgorithm[1];
-		hashesAlgo[0] = HashAlgorithm.SHA512;
-		ProtocolP2PPacketTCP d = new ProtocolP2PPacketTCP((Payload) new HashRequest(filename, hashesAlgo));
-		try {
-			d.sendRequest((Object)hostItem.getTCPSocket());
-			try {
-				Payload pHash = d.receiveResponse().getPayload();
-				assert pHash instanceof HashResponse : "This payload must be instance of HashResponse";
-				if (!(pHash instanceof HashResponse)) {
-					throw new InternalError();
-				} else {
-					hash = ((HashResponse)pHash).getHash(HashAlgorithm.SHA512);
-				}
-			} catch (EmptyDirectory e) {
-				hash = new byte[0];
-			} catch (NotFound e) {
-				hash = new byte[0];
-				// TODO: use more specific errors
-			} catch (EmptyFile e) {
-				throw new InternalError();
-			} catch (ProtocolError e) {
-				throw new InternalError();
-			} catch (InternalRemoteError e) {
-				throw new InternalError();
-			} catch (VersionRemoteError e) {
-				throw new InternalError();
-			} catch (ProtocolRemoteError e) {
-				throw new InternalError();
-			} catch (TransmissionError e) {
-				throw new InternalError();
-			} catch (VersionError e) {
-				throw new InternalError();
-			} catch (SizeError e) {
-				throw new InternalError();
-			}
-			return hash;
-		} catch (IOException e) {
-			throw new InternalError();
-		} catch (SocketClosed e){
-			System.err.println("getHashSum512 : SocketClosed");
-			throw new InternalError();
-		}
+	public ClientDownloadTCP(String filename, List<HostItem> hostList, String partsSubdir, String dirStorage, Logger logger) {
+		super(filename, hostList, partsSubdir, dirStorage, logger);
 	}
 
-	/** Removes servers not owning the correct file to download from list.
-	 * This is done by comparing hash512sum.
-	 * @throws	InternalError
+	/** Create a clientDownloadPart
+	 * @param filename	name of the file to download
+	 * @param hostItem	Hostitem of the server
 	 */
-	private void purgeList() throws InternalError {
-		List<HostItem> blackList = new ArrayList<HostItem>();
-		boolean first = false;
-		byte[] hashsum;
-		for(HostItem host: hostList) {
-			// already have hashsum from 1st server
-			if (!first) {
-				first = true;
-				continue;
-			}
-			// ask hashsum
-			hashsum = getHashSum512(host);
-			if (!Arrays.equals(hash512, hashsum)) {
-				blackList.add(host);
-			}
-		}
-		// purge list
-		for(HostItem host: blackList) {
-			hostList.remove(host);
-		}
-		System.err.println("Host list purge: done");
+	protected ClientDownloadPart createDownloadPart(String filename, HostItem hostItem) {
+		return (ClientDownloadPart)new ClientDownloadPartTCP((ClientDownload)this, filename, hostItem.getTCPSocket(), partsSubdir, logger);
 	}
-
-	/** Getter for hash512sum
-	 * @return	hash512sum
+	
+	/** Close HostItem socket
+	 * @param hostItem	HostItem
 	 */
-	public byte[] getHashSum512() {
-		return hash512;
+	protected void closeHostItemSocket(HostItem hostItem) {
+		hostItem.closeTCPSocket();
 	}
 
-	/** Initialize infos about file to download (size, hash512sum, partslist to dl).
-	 * Also download first partfile (to get size).
-	 * @throws	InternalError
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
 	 */
-	private void init() throws InternalError {
-		// get size
-		setSize();
-
-		// get hashsum from 1st server in list
-		hash512 = getHashSum512(hostList.get(0));
-		if (hash512.length == 0) {
-			System.err.println("Error: no hash512sum support.");
-			throw new InternalError();
-		}
-
-		// Add tasks
-		if (!stop) {
-			for(long i=MAX_PARTIAL_SIZE; i<size;i+=MAX_PARTIAL_SIZE) {
-				offsetsToAsk.add(Long.valueOf(i));
-			}
-			System.err.println("Adding tasks: done");
-		}
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeTCP(text, logLevel);
 	}
 
-	/** Set size of file to download. Also download first file part.
-	 * @throws InternalError
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
 	 */
-	private void setSize() throws InternalError {
-		ProtocolP2PPacketTCP d = new ProtocolP2PPacketTCP((Payload) new LoadRequest(filename, 0, MAX_PARTIAL_SIZE));
-		try {
-			d.sendRequest((Object)hostList.get(0).getTCPSocket());
-			try {
-				Payload p = d.receiveResponse().getPayload();
-				assert p instanceof FilePart : "This payload must be instance of FilePart";
-				if (!(p instanceof FilePart)) {
-					System.err.println("Error: cannot get size.");
-					throw new InternalError();
-				} else {
-					FilePart fp = (FilePart)p;
-					if (!fp.getFilename().equals(filename)) {
-						System.err.println("Error: wrong file received: `" + fp.getFilename() + "`");
-						throw new ProtocolError();
-					}
-					if (fp.getOffset() == 0) {
-						try {
-							Files.write(new File(partsSubdir + filename + "_0.part").toPath(), fp.getPartialContent());
-						} catch (IOException e) {
-							System.err.println("Error: cannot write file (" + partsSubdir + filename + "_0.part)");
-						}
-						size = fp.getTotalSize();
-						if (fp.getPartialContent().length == size) {
-							stop = true;
-						}
-					} else {
-						System.err.println("Error: wrong file part received.");
-						throw new InternalError();
-					}
-				}
-			} catch (EmptyDirectory e) {
-				System.err.println("Error: empty directory.");
-				throw new InternalError();
-			} catch (EmptyFile e) {
-				// TODO: use more specific errors
-				throw new InternalError();
-			} catch (ProtocolError e) {
-				throw new InternalError();
-			} catch (InternalRemoteError e) {
-				throw new InternalError();
-			} catch (VersionRemoteError e) {
-				throw new InternalError();
-			} catch (ProtocolRemoteError e) {
-				throw new InternalError();
-			} catch (TransmissionError e) {
-				throw new InternalError();
-			} catch (VersionError e) {
-				throw new InternalError();
-			} catch (SizeError e) {
-				throw new InternalError();
-			} catch (NotFound e) {
-				throw new InternalError();
-			}
-		} catch (IOException e) {
-			throw new InternalError();
-		} catch (SocketClosed e){
-			System.err.println("setSize : SocketClosed");
-		}
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeTCP(e, logLevel);
 	}
 
-	/** Success getter.
-	 * @return	true when file have successfully been reassembled.
+	/** Create packets
+	 * @param payload	Payload
 	 */
-	public boolean getSuccess() {
-		return success;
+	protected < T extends Payload > ProtocolP2PPacket<T> createProtocolP2PPacket(T payload) {
+		return (ProtocolP2PPacket<T>)new ProtocolP2PPacketTCP<T>(payload);
 	}
 
-	/** Reassemble file from file parts.
-	 * Set success to true if file is reassembled successfully.
+	/** Getter for HostItem socket
+	 * @param hostItem	HostItem
 	 */
-	private void reassembleFile() {
-		boolean firstPart = true;
-		boolean abort = false;
-		long nextOffset = 0;
-		do {
-			if (firstPart) {
-				System.err.println("Reassembling: First part");
-				try {
-					// create file
-					Files.copy(new File(partsSubdir + filename + "_" + nextOffset + ".part").toPath(), new File(dirStorage + filename).toPath(), StandardCopyOption.REPLACE_EXISTING);
-					nextOffset = (new File(dirStorage + filename)).length();
-					firstPart = false;
-				} catch (IOException e) {
-					System.err.println("Reassembling: aborting on first part");
-					abort = true;
-				}
-			} else if (nextOffset >= size) {
-				success = true;
-				System.err.println("Reassembling: success");
-			} else {
-				// append to file
-				try {
-					Files.write(new File(dirStorage + filename).toPath(), Files.readAllBytes(new File(partsSubdir + filename + "_" + nextOffset + ".part").toPath()), StandardOpenOption.APPEND);
-					nextOffset = (new File(dirStorage + filename)).length();
-				} catch (IOException e) {
-					abort = true;
-					System.err.println("Aborting: bad number " + nextOffset);
-				}
-			}
-		} while((!success) && (!abort));
+	protected Object getHostItemSocket(HostItem hostItem) {
+		return (Object)hostItem.getTCPSocket();
 	}
 }

src/clientP2P/ClientDownloadUDP.java

@@ -1,34 +1,40 @@
 package clientP2P;
-import clientP2P.ClientDownloadPartUDP;
-import tools.HostItem;
+
 import java.util.List;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Random;
+import java.io.IOException;
+import java.io.File;
+import java.nio.file.Files;
+import java.nio.file.StandardOpenOption;
+import java.nio.file.StandardCopyOption;
+import localException.ProtocolError;
+import localException.InternalError;
+import localException.TransmissionError;
+import localException.SizeError;
+import localException.VersionError;
 import remoteException.EmptyDirectory;
 import remoteException.EmptyFile;
 import remoteException.VersionRemoteError;
 import remoteException.ProtocolRemoteError;
 import remoteException.NotFound;
 import remoteException.InternalRemoteError;
+import remoteException.NotATracker;
 import protocolP2P.HashAlgorithm;
 import protocolP2P.HashResponse;
 import protocolP2P.HashRequest;
 import protocolP2P.ProtocolP2PPacketUDP;
+import protocolP2P.ProtocolP2PPacket;
 import protocolP2P.Payload;
-import exception.ProtocolError;
-import exception.InternalError;
-import exception.TransmissionError;
-import exception.SizeError;
-import exception.VersionError;
 import protocolP2P.FilePart;
 import protocolP2P.LoadRequest;
-import java.io.IOException;
-import java.nio.file.Files;
-import java.io.File;
-import java.nio.file.Paths;
-import java.nio.file.StandardOpenOption;
-import java.nio.file.StandardCopyOption;
+import clientP2P.ClientDownloadPartUDP;
+import clientP2P.ClientDownload;
+import tools.HostItem;
+import tools.Logger;
+import tools.LogLevel;
+
 
 /** Class to download file from udp
 * @author	Louis Royer
@@ -36,348 +42,61 @@ import java.nio.file.StandardCopyOption;
 * @author	JS Auge
 * @version	1.0
 */
-public class ClientDownloadUDP implements Runnable {
-
-	private List<HostItem> hostList;
-	private String filename;
-	private byte[] hash512;
-	private List<ClientDownloadPartUDP> sockList = new ArrayList<ClientDownloadPartUDP>();
-	private List<Long> offsetsToAsk = new ArrayList<Long>();
-	private List<Long> offsetsPending = new ArrayList<Long>();
-	private boolean stop;
-	private long size;
-	private static final long MAX_PARTIAL_SIZE = 4096;
-	private String partsSubdir;
-	private String dirStorage;
-	private boolean success = false;
+public class ClientDownloadUDP extends ClientDownload {
 
 	/** Constructor with parameters: filename, list of hosts, parts subdirectory and dirStorage
 	 * @param filename	name of file to download
 	 * @param hostList	list of servers
 	 * @param partsSubdir	directory to store .part files
 	 * @param dirStorage	directory to write assembled file
+	 * @param logger	Logger
 	 */
-	public ClientDownloadUDP(String filename, List<HostItem> hostList, String partsSubdir, String dirStorage) {
-		this.partsSubdir = partsSubdir;
-		this.dirStorage = dirStorage;
-		this.filename = filename;
-		this.hostList = hostList;
-		this.stop = false;
-	}
-
-	/** Asks thread to stop
-	 */
-	public void setStop() {
-		stop = true;
-	}
-	
-	/** Runnable implementation
-	 */
-	public void run() {
-		try {
-			init();
-			if (stop) {
-				System.err.println("File is smaller than part max size.");
-				hostList.get(0).closeUDPSocket();
-			} else {
-				System.err.println("File is bigger than part max size.");
-				purgeList();
-				initThreads();
-				while(!stop) {
-					assignTasks();
-					checkTasksStatus();
-
-				}
-			}
-			System.err.println("Reassembling file parts.");
-			reassembleFile();
-		} catch(InternalError e) {
-			System.err.println("Error while downloading file. Aborting.");
-		} finally {
-			stopTasks();
-		}
-	}
-
-	/** Starts threads for each server in hostList.
-	 */
-	private void initThreads() {
-		for(HostItem hostItem: hostList) {
-			sockList.add(new ClientDownloadPartUDP(this, filename, hostItem.getUDPSocket(), partsSubdir));
-		}
-		for(ClientDownloadPartUDP c: sockList) {
-			Thread t = new Thread(c);
-			t.start();
-		}
-		System.err.println("Threads initialized");
-	}
-
-	/** Remove tasks from failed threads. Update done status.
-	 * @throws	InternalError
-	 */
-	private void checkTasksStatus() throws InternalError {
-		try {
-			synchronized(this) {
-				this.wait();
-				List<ClientDownloadPartUDP> sockListCpy = new ArrayList<>(sockList);
-				for(ClientDownloadPartUDP c: sockListCpy) {
-					if (c.hasFailed() == true) {
-						sockList.remove(c);
-						offsetsPending.removeAll(c.getFailed());
-						offsetsToAsk.addAll(c.getFailed());
-					}
-					try {
-						offsetsPending.removeAll(c.getDone());
-					} catch (InterruptedException e) {
-						throw new InternalError();
-					}
-				}
-				System.err.println("Task check status: " + offsetsToAsk.size() + " to asks, " + offsetsPending.size() + " pending");
-				if (offsetsToAsk.isEmpty() && offsetsPending.isEmpty()) {
-					stop = true;
-				}
-				if (sockList.size() == 0) {
-					System.err.println("No thread working");
-					throw new InternalError();
-				}
-			}
-		} catch (InterruptedException e) {
-			throw new InternalError();
-		}
-	}
-
-	/** Assign tasks randomly to threads.
-	 * @throws	InternalError
-	 */
-	private void assignTasks() throws InternalError {
-		Random rand = new Random();
-		for(long offset : offsetsToAsk) {
-			try {
-				sockList.get(rand.nextInt(sockList.size())).assignTask(offset);
-				offsetsPending.add(offset);
-				System.err.println("Assigned task "+ offset);
-			} catch(InterruptedException e) {
-				throw new InternalError();
-			}
-		}
-		offsetsToAsk.removeAll(offsetsPending);
-	}
-
-	/** Stop threads */
-	private void stopTasks() {
-		for(ClientDownloadPartUDP c : sockList) {
-			try {
-				c.setStop();
-			} catch (InterruptedException e) {}
-		}
-	}
-
-	/** Get hashsum from server.
-	 * @param hostItem	server to ask hash
-	 * @return	hash512sum
-	 * @throws	InternalError
-	 */
-	private byte[] getHashSum512(HostItem hostItem) throws InternalError {
-		byte[] hash;
-		HashAlgorithm[] hashesAlgo = new HashAlgorithm[1];
-		hashesAlgo[0] = HashAlgorithm.SHA512;
-		ProtocolP2PPacketUDP d = new ProtocolP2PPacketUDP((Payload) new HashRequest(filename, hashesAlgo));
-		try {
-			d.sendRequest((Object)hostItem.getUDPSocket());
-			try {
-				Payload pHash = d.receiveResponse().getPayload();
-				assert pHash instanceof HashResponse : "This payload must be instance of HashResponse";
-				if (!(pHash instanceof HashResponse)) {
-					throw new InternalError();
-				} else { 
-					hash = ((HashResponse)pHash).getHash(HashAlgorithm.SHA512);
-				}
-			} catch (EmptyDirectory e) {
-				hash = new byte[0];
-			} catch (NotFound e) {
-				hash = new byte[0];
-				// TODO: use more specific errors
-			} catch (EmptyFile e) {
-				throw new InternalError();
-			} catch (ProtocolError e) {
-				throw new InternalError();
-			} catch (InternalRemoteError e) {
-				throw new InternalError();
-			} catch (VersionRemoteError e) {
-				throw new InternalError();
-			} catch (ProtocolRemoteError e) {
-				throw new InternalError();
-			} catch (TransmissionError e) {
-				throw new InternalError();
-			} catch (VersionError e) {
-				throw new InternalError();
-			} catch (SizeError e) {
-				throw new InternalError();
-			}
-			return hash;
-		} catch (IOException e) {
-			throw new InternalError();
-		}
+	public ClientDownloadUDP(String filename, List<HostItem> hostList, String partsSubdir, String dirStorage, Logger logger) {
+		super(filename, hostList, partsSubdir, dirStorage, logger);
 	}
 
-	/** Removes servers not owning the correct file to download from list.
-	 * This is done by comparing hash512sum.
-	 * @throws	InternalError
+	/** Create a clientDownloadPart
+	 * @param filename	name of the file to download
+	 * @param hostItem	Hostitem of the server
 	 */
-	private void purgeList() throws InternalError {
-		List<HostItem> blackList = new ArrayList<HostItem>();
-		boolean first = false;
-		byte[] hashsum;
-		for(HostItem host: hostList) {
-			// already have hashsum from 1st server
-			if (!first) {
-				first = true;
-				continue;
-			}
-			// ask hashsum
-			hashsum = getHashSum512(host);
-			if (!Arrays.equals(hash512, hashsum)) {
-				blackList.add(host);
-			}
-		}
-		// purge list
-		for(HostItem host: blackList) {
-			hostList.remove(host);
-		}
-		System.err.println("Host list purge: done");
+	protected ClientDownloadPart createDownloadPart(String filename, HostItem hostItem) {
+		return (ClientDownloadPart)new ClientDownloadPartUDP((ClientDownload)this, filename, hostItem.getUDPSocket(), partsSubdir, logger);
 	}
 
-	/** Getter for hash512sum
-	 * @return	hash512sum
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
 	 */
-	public byte[] getHashSum512() {
-		return hash512;
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeUDP(text, logLevel);
 	}
 
-	/** Initialize infos about file to download (size, hash512sum, partslist to dl).
-	 * Also download first partfile (to get size).
-	 * @throws	InternalError
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
 	 */
-	private void init() throws InternalError {
-		// get size
-		setSize();
-		
-		// get hashsum from 1st server in list
-		hash512 = getHashSum512(hostList.get(0));
-		if (hash512.length == 0) {
-			System.err.println("Error: no hash512sum support.");
-			throw new InternalError();
-		}
-		
-		// Add tasks
-		if (!stop) {
-			for(long i=MAX_PARTIAL_SIZE; i<size;i+=MAX_PARTIAL_SIZE) {
-				offsetsToAsk.add(Long.valueOf(i));
-			}
-			System.err.println("Adding tasks: done");
-		}
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeUDP(e, logLevel);
 	}
 
-	/** Set size of file to download. Also download first file part.
-	 * @throws InternalError
+	/** Create packets
+	 * @param payload	Payload
 	 */
-	private void setSize() throws InternalError {
-		ProtocolP2PPacketUDP d = new ProtocolP2PPacketUDP((Payload) new LoadRequest(filename, 0, MAX_PARTIAL_SIZE));
-		try {
-			d.sendRequest((Object)hostList.get(0).getUDPSocket());
-			try {
-				Payload p = d.receiveResponse().getPayload();
-				assert p instanceof FilePart : "This payload must be instance of FilePart";
-				if (!(p instanceof FilePart)) {
-					System.err.println("Error: cannot get size.");
-					throw new InternalError();
-				} else {
-					FilePart fp = (FilePart)p;
-					if (!fp.getFilename().equals(filename)) {
-						System.err.println("Error: wrong file received: `" + fp.getFilename() + "`");
-						throw new ProtocolError();
-					}
-					if (fp.getOffset() == 0) {
-						try {
-							Files.write(new File(partsSubdir + filename + "_0.part").toPath(), fp.getPartialContent());
-						} catch (IOException e) {
-							System.err.println("Error: cannot write file (" + partsSubdir + filename + "_0.part)");
-						}
-						size = fp.getTotalSize();
-						if (fp.getPartialContent().length == size) {
-							stop = true;
-						}
-					} else {
-						System.err.println("Error: wrong file part received.");
-						throw new InternalError();
-					}
-				}
-			} catch (EmptyDirectory e) {
-				System.err.println("Error: empty directory.");
-				throw new InternalError();
-			} catch (EmptyFile e) {
-				// TODO: use more specific errors
-				throw new InternalError();
-			} catch (ProtocolError e) {
-				throw new InternalError();
-			} catch (InternalRemoteError e) {
-				throw new InternalError();
-			} catch (VersionRemoteError e) {
-				throw new InternalError();
-			} catch (ProtocolRemoteError e) {
-				throw new InternalError();
-			} catch (TransmissionError e) {
-				throw new InternalError();
-			} catch (VersionError e) {
-				throw new InternalError();
-			} catch (SizeError e) {
-				throw new InternalError();
-			} catch (NotFound e) {
-				throw new InternalError();
-			}
-		} catch (IOException e) {
-			throw new InternalError();
-		}
+	protected < T extends Payload > ProtocolP2PPacket<T> createProtocolP2PPacket(T payload) {
+		return (ProtocolP2PPacket<T>)new ProtocolP2PPacketUDP<T>(payload);
 	}
 
-	/** Success getter.
-	 * @return	true when file have successfully been reassembled.
+	/** Getter for HostItem socket
+	 * @param hostItem	HostItem
 	 */
-	public boolean getSuccess() {
-		return success;
+	protected Object getHostItemSocket(HostItem hostItem) {
+		return (Object)hostItem.getUDPSocket();
 	}
 
-	/** Reassemble file from file parts.
-	 * Set success to true if file is reassembled successfully.
+	/** Close HostItem socket
+	 * @param hostItem	HostItem
 	 */
-	private void reassembleFile() {
-		boolean firstPart = true;
-		boolean abort = false;
-		long nextOffset = 0;
-		do {
-			if (firstPart) {
-				System.err.println("Reassembling: First part");
-				try {
-					// create file
-					Files.copy(new File(partsSubdir + filename + "_" + nextOffset + ".part").toPath(), new File(dirStorage + filename).toPath(), StandardCopyOption.REPLACE_EXISTING);
-					nextOffset = (new File(dirStorage + filename)).length();
-					firstPart = false;
-				} catch (IOException e) {
-					System.err.println("Reassembling: aborting on first part");
-					abort = true;
-				}
-			} else if (nextOffset >= size) {
-				success = true;
-				System.err.println("Reassembling: success");
-			} else {
-				// append to file
-				try {
-					Files.write(new File(dirStorage + filename).toPath(), Files.readAllBytes(new File(partsSubdir + filename + "_" + nextOffset + ".part").toPath()), StandardOpenOption.APPEND);
-					nextOffset = (new File(dirStorage + filename)).length();
-				} catch (IOException e) {
-					abort = true;
-					System.err.println("Aborting: bad number " + nextOffset);
-				}
-			}
-		} while((!success) && (!abort));
+	protected void closeHostItemSocket(HostItem hostItem) {
+		hostItem.closeUDPSocket();
 	}
 }

src/clientP2P/ClientManagement.java

@@ -0,0 +1,262 @@
+package clientP2P;
+import tools.HostItem;
+import tools.Logger;
+import tools.LogLevel;
+import java.util.Scanner;
+import java.util.List;
+import localException.ProtocolError;
+import tools.ServeErrors;
+import protocolP2P.RequestResponseCode;
+import protocolP2P.FileList;
+import protocolP2P.ProtocolP2PPacket;
+import protocolP2P.DiscoverRequest;
+import protocolP2P.DiscoverResponse;
+import protocolP2P.Payload;
+import protocolP2P.HashAlgorithm;
+import localException.InternalError;
+import localException.ProtocolError;
+import localException.SizeError;
+import localException.TransmissionError;
+import localException.VersionError;
+import localException.SocketClosed;
+import remoteException.EmptyFile;
+import remoteException.EmptyDirectory;
+import remoteException.InternalRemoteError;
+import remoteException.NotFound;
+import remoteException.ProtocolRemoteError;
+import remoteException.VersionRemoteError;
+import remoteException.NotATracker;
+import java.io.IOException;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.net.UnknownHostException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.Arrays;
+
+
+/** Implementation of P2P-JAVA-PROJECT CLIENT
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public abstract class ClientManagement extends ServeErrors implements Runnable {
+	protected String baseDirectory;
+	protected String partsSubdir;
+	protected List<HostItem> hostList;
+	protected HostItem tracker;
+	protected Logger logger;
+	protected Scanner scanner;
+	protected ClientDownload downLoader;
+	
+	/** Constructor with baseDirectory, tracker, partsSubdir, logger, and scanner parameters.
+	 * @param baseDirectory	the root directory where files are stored
+	 * @param tracker Tracker hostItem
+	 * @param partsSubdir	subdirectory to store file parts
+	 * @param logger	Loggger
+	 * @param scanner	Scanner used to read input
+	 */
+	public ClientManagement(String baseDirectory, HostItem tracker, String partsSubdir, Logger logger, Scanner scanner) {
+		this.scanner = scanner;
+		this.baseDirectory = baseDirectory;
+		this.tracker = tracker;
+		this.partsSubdir = partsSubdir;
+		this.logger = logger;
+		try {
+			initHostList();
+		} catch (InternalError e) {
+			System.exit(-1);
+		} catch (ProtocolError e) {
+			System.exit(-2);
+		}
+	}
+
+	/** Getter for tracker socket
+	 */
+	protected abstract Object getTrackerSocket(); 
+
+
+	/** Initialize hostList from tracker
+	 * @throws	ProtocolError
+	 * @throws	InternalError
+	 */
+	private void initHostList() throws ProtocolError, InternalError {
+		ProtocolP2PPacket<?> d = createProtocolP2PPacket(new DiscoverRequest(null));
+		try {
+			d.sendRequest(getTrackerSocket());
+			Payload p = d.receiveResponse().getPayload();
+			assert p instanceof DiscoverResponse : "This payload must be instance of Filelist";
+			if (!(p instanceof DiscoverResponse)) {
+				throw new InternalError();
+			} else {
+				hostList = ((DiscoverResponse)p).getHostList();
+			}
+		} catch (SocketClosed e){
+			writeLog("listDirectory : SocketClosed", LogLevel.Error);
+			throw new ProtocolError();
+		} catch (NotATracker e) {
+			writeLog(e, LogLevel.Error);
+			throw new ProtocolError();
+		} catch (Exception e) {
+			writeLog(e, LogLevel.Error);
+			throw new ProtocolError();
+		}
+	}
+
+	/** Compute Hashsum of a file.
+	 * @param	filename
+	 * @return	hashsum
+	 */
+	protected byte[] computeHashsum(String filename, HashAlgorithm h) {
+		try {
+			MessageDigest md = MessageDigest.getInstance(HashAlgorithm.SHA512.getName());
+			return md.digest(Files.readAllBytes(Paths.get(baseDirectory + filename)));
+		} catch (NoSuchAlgorithmException e) {
+			writeLog(h.getName() + " not supported", LogLevel.Error);
+		} catch (IOException e) {
+			writeLog("cannot read " + filename, LogLevel.Error);
+		}
+		return new byte[0];
+	}
+
+	/** Getter for HostItem socket
+	 * @param hostItem	HostItem
+	 */
+	protected abstract Object getHostItemSocket(HostItem hostItem);
+
+	/** list server’s directory content
+	 * @return	list of files
+	 * @throws	InternalError
+	 * @throws	UnknowHostException
+	 * @throws	IOException
+	 * @throws	TransmissionError
+	 * @throws	ProtocolError
+	 * @throws	VersionError
+	 * @throws	SizeError
+	 * @throws	EmptyDirectory
+	 * @throws	InternalRemoteError
+	 * @throws	ProtocolRemoteError
+	 * @throws	VersionRemoteError
+	 */
+	protected String[] listDirectory() throws EmptyDirectory, InternalError, UnknownHostException, IOException, TransmissionError, ProtocolError, VersionError, SizeError, InternalRemoteError, ProtocolRemoteError, VersionRemoteError {
+		ProtocolP2PPacket<?> d = createProtocolP2PPacket(new Payload(RequestResponseCode.LIST_REQUEST));
+		try {
+			d.sendRequest(getHostItemSocket(hostList.get(0)));
+			Payload p = d.receiveResponse().getPayload();
+			assert p instanceof FileList : "This payload must be instance of Filelist";
+			if (!(p instanceof FileList)) {
+				throw new InternalError();
+			} else {
+				return ((FileList)p).getFileList();
+			}
+		} catch (NotFound e) {
+			writeLog(e, LogLevel.Error);
+			throw new ProtocolError();
+		} catch (EmptyFile e) {
+			writeLog(e, LogLevel.Error);
+			throw new ProtocolError();
+		} catch (SocketClosed e){
+			writeLog("listDirectory : SocketClosed", LogLevel.Error);
+			throw new ProtocolError();
+		} catch (NotATracker e) {
+			writeLog(e, LogLevel.Error);
+			throw new ProtocolError();
+		}
+	}
+
+	/** Initialize downloader
+	 * @param filename	Name of the file to download
+	 */
+	protected abstract void initDownloader(String filename);
+
+	/** Try to download a file
+	 * @param filename	name of the file to download
+	 * @throws	NotFound
+	 * @throws	InternalError
+	 * @throws	UnknownHostException
+	 * @throws	IOException
+	 * @throws	TransmissionError
+	 * @throws	ProtocolError
+	 * @throws	VersionError
+	 * @throws	SizeError
+	 * @throws	InternalRemoteError
+	 * @throws	ProtocolRemoteError
+	 * @throws	VersionRemoteError
+	 * @throws	EmptyFile
+	 */
+	private void download(String filename) throws EmptyFile, NotFound, InternalError, UnknownHostException, IOException, TransmissionError, ProtocolError, VersionError, SizeError, InternalRemoteError, ProtocolRemoteError, VersionRemoteError {
+		initDownloader(filename);
+		Thread t = new Thread(downLoader);
+		t.start();
+		try {
+			t.join();
+			if (downLoader.getSuccess()) {
+				byte[] hash512 = downLoader.getHashSum512();
+				if (!Arrays.equals(hash512, computeHashsum(filename, HashAlgorithm.SHA512))) {
+					writeLog("Hashsum does not match", LogLevel.Error);
+					String line = "Computed checksum:\n";
+					byte[] c = computeHashsum(filename, HashAlgorithm.SHA512);
+					for (byte b: c) {
+						line += String.format("%02X", b);
+					}
+					line += "\nReceived checksum:\n";
+					for (byte b: hash512) {
+						line += String.format("%02X", b);
+					}
+					line += "\n";
+					writeLog(line, LogLevel.Info);
+					throw new InternalError();
+				}
+			} else {
+				throw new InternalError();
+			}
+		} catch (InterruptedException e) {
+			throw new InternalError();
+		}
+	}
+
+	/** Implementation of Runnable
+	 */
+	public void run() {
+		try {
+			String[] list = listDirectory();
+			System.out.println("Files present on the server:");
+			for(String listItem: list) {
+				System.out.println(listItem);
+			}
+			System.out.println("Name of the file to download:");
+			String f = scanner.nextLine();
+			download(f);
+			System.out.println("File " + f + " sucessfully downloaded");
+			writeLog("File " + f + " sucessfully downloaded", LogLevel.Info);
+		} catch (EmptyDirectory e) {
+			writeLog("Server has no file in directory", LogLevel.Error);
+		} catch (InternalError e) {
+			writeLog("Client internal error", LogLevel.Error);
+		} catch (UnknownHostException e) {
+			writeLog("Server host is unknown", LogLevel.Error);
+		} catch (IOException e) {
+			writeLog("Request cannot be send or response cannot be received", LogLevel.Error);
+		} catch (TransmissionError e) {
+			writeLog("Message received is too big", LogLevel.Error);
+		} catch (ProtocolError e) {
+			writeLog("Cannot decode server’s response", LogLevel.Error);
+		} catch (VersionError e) {
+			writeLog("Server’s response use bad version of the protocol", LogLevel.Error);
+		} catch (SizeError e) {
+			writeLog("Cannot handle this packets because of internal representation limitations of numbers on the client", LogLevel.Error);
+		} catch (InternalRemoteError e) {
+			writeLog("Server internal error", LogLevel.Error);
+		} catch (ProtocolRemoteError e) {
+			writeLog("Server cannot decode client’s request", LogLevel.Error);
+		} catch (VersionRemoteError e) {
+			writeLog("Server cannot decode this version of the protocol", LogLevel.Error);
+		} catch (NotFound e) {
+			writeLog("Server has not this file in directory", LogLevel.Error);
+		} catch (EmptyFile e) {
+			writeLog("File is empty", LogLevel.Error);
+		}
+	}
+
+}

src/clientP2P/ClientManagementTCP.java

@@ -1,38 +1,15 @@
 package clientP2P;
-import exception.InternalError;
-import exception.ProtocolError;
-import exception.SizeError;
-import exception.TransmissionError;
-import exception.VersionError;
-import remoteException.EmptyFile;
-import remoteException.EmptyDirectory;
-import remoteException.InternalRemoteError;
-import remoteException.NotFound;
-import remoteException.ProtocolRemoteError;
-import remoteException.VersionRemoteError;
-import java.net.UnknownHostException;
+
 import java.util.Scanner;
-import java.io.IOException;
-import java.nio.file.Files;
-import java.io.File;
-import java.nio.file.Paths;
-import java.nio.file.StandardOpenOption;
-import java.util.Arrays;
-import java.util.List;
-import tools.HostItem;
-import protocolP2P.ProtocolP2PPacketTCP;
 import protocolP2P.Payload;
-import protocolP2P.RequestResponseCode;
-import protocolP2P.FileList;
-import protocolP2P.FilePart;
-import protocolP2P.LoadRequest;
-import protocolP2P.HashAlgorithm;
-import protocolP2P.HashRequest;
-import protocolP2P.HashResponse;
-import java.security.MessageDigest;
-import java.security.NoSuchAlgorithmException;
+import protocolP2P.ProtocolP2PPacket;
+import protocolP2P.ProtocolP2PPacketTCP;
+import tools.HostItem;
+import tools.Logger;
+import tools.LogLevel;
 import clientP2P.ClientDownloadTCP;
-import exception.SocketClosed;
+import clientP2P.ClientManagement;
+
 
 /** Implementation of P2P-JAVA-PROJECT CLIENT
  * @author	Louis Royer
@@ -40,160 +17,60 @@ import exception.SocketClosed;
  * @author	JS Auge
  * @version	1.0
  */
-public class ClientManagementTCP implements Runnable {
-	private String baseDirectory;
-	private String partsSubdir;
-	private List<HostItem> hostList;
-
-	/** Constructor for TCP implementation, with baseDirectory and TCPPort parameters.
+public class ClientManagementTCP extends ClientManagement {
+	/** Constructor for TCP implementation, with baseDirectory, tracker, partsSubdir, logger, and scanner parameters.
 	 * @param baseDirectory	the root directory where files are stored
-	 * @param host	hostname of the server
-	 * @param TCPPort	the server will listen on this port
+	 * @param tracker Tracker hostItem
+	 * @param partsSubdir	subdirectory to store file parts
+	 * @param logger	Loggger
+	 * @param scanner	Scanner used to read input
+	 */
+	public ClientManagementTCP(String baseDirectory, HostItem tracker, String partsSubdir, Logger logger, Scanner scanner) {
+		super(baseDirectory, tracker, partsSubdir, logger, scanner);
+	}
+
+	/** Initialize downloader
+	 * @param filename	Name of the file to download
+	 */
+	protected void initDownloader(String filename) {
+		downLoader = (ClientDownload) new ClientDownloadTCP(filename, hostList, partsSubdir, baseDirectory, logger);
+	}
+	
+
+
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
 	 */
-	public ClientManagementTCP(String baseDirectory, List<HostItem> hostList, String partsSubdir) {
-		this.baseDirectory = baseDirectory;
-		this.hostList = hostList;
-		this.partsSubdir = partsSubdir;
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeTCP(text, logLevel);
 	}
 
-	/** Implementation of Runnable
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
 	 */
-	public void run() {
-		try {
-			System.out.println("Enter all servers: type \"stop\" when finished");
-			Scanner scanner = new Scanner(System.in);
-			String[] list = listDirectory();
-			System.out.println("Files present on the server:");
-			for(String listItem: list) {
-				System.out.println(listItem);
-			}
-			System.out.println("Name of the file to download:");
-			String f = scanner.nextLine();
-			download(f);
-			System.out.println("File sucessfully downloaded");
-		} catch (EmptyDirectory e) {
-			System.err.println("Error: Server has no file in directory");
-		} catch (InternalError e) {
-			System.err.println("Error: Client internal error");
-		} catch (UnknownHostException e) {
-			System.err.println("Error: Server host is unknown");
-		} catch (IOException e) {
-			System.err.println("Error: Request cannot be send or response cannot be received");
-		} catch (TransmissionError e) {
-			System.err.println("Error: Message received is too big");
-		} catch (ProtocolError e) {
-			System.err.println("Error: Cannot decode server’s response");
-		} catch (VersionError e) {
-			System.err.println("Error: Server’s response use bad version of the protocol");
-		} catch (SizeError e) {
-			System.err.println("Error: Cannot handle this packets because of internal representation limitations of numbers on the client");
-		} catch (InternalRemoteError e) {
-			System.err.println("Error: Server internal error");
-		} catch (ProtocolRemoteError e) {
-			System.err.println("Error: Server cannot decode client’s request");
-		} catch (VersionRemoteError e) {
-			System.err.println("Error: Server cannot decode this version of the protocol");
-		} catch (NotFound e) {
-			System.err.println("Error: Server has not this file in directory");
-		} catch (EmptyFile e) {
-			System.err.println("Error: File is empty");
-		}
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeTCP(e, logLevel);
 	}
 
-	/** Try to download a file
-	 * @param filename	name of the file to download
-	 * @throws	NotFound
-	 * @throws	InternalError
-	 * @throws	UnknownHostException
-	 * @throws	IOException
-	 * @throws	TransmissionError
-	 * @throws	ProtocolError
-	 * @throws	VersionError
-	 * @throws	SizeError
-	 * @throws	InternalRemoteError
-	 * @throws	ProtocolRemoteError
-	 * @throws	VersionRemoteError
-	 * @throws	EmptyFile
+	/** Create packets
+	 * @param payload	Payload
 	 */
-	private void download(String filename) throws EmptyFile, NotFound, InternalError, UnknownHostException, IOException, TransmissionError, ProtocolError, VersionError, SizeError, InternalRemoteError, ProtocolRemoteError, VersionRemoteError {
-		ClientDownloadTCP downLoader = new ClientDownloadTCP(filename, hostList, partsSubdir, baseDirectory);
-		Thread t = new Thread(downLoader);
-		t.start();
-		try {
-			t.join();
-			if (downLoader.getSuccess()) {
-				byte[] hash512 = downLoader.getHashSum512();
-				if (!Arrays.equals(hash512, computeHashsum(filename, HashAlgorithm.SHA512))) {
-					System.err.println("Error: Hashsum does not match");
-					System.err.println("Computed checksum:");
-					byte[] c = computeHashsum(filename, HashAlgorithm.SHA512);
-					for (byte b: c) {
-						System.err.print(String.format("%02X", b));
-					}
-					System.err.println("");
-					System.err.println("Received checksum:");
-					for (byte b: hash512) {
-						System.err.print(String.format("%02X", b));
-					}
-					System.err.println("");
-					throw new InternalError();
-				}
-			} else {
-				throw new InternalError();
-			}
-		} catch (InterruptedException e) {
-			throw new InternalError();
-		}
+	protected < T extends Payload > ProtocolP2PPacket<T> createProtocolP2PPacket(T payload) {
+		return (ProtocolP2PPacket<T>)new ProtocolP2PPacketTCP<T>(payload);
 	}
 
-	/** list server’s directory content
-	 * @return	list of files
-	 * @throws	InternalError
-	 * @throws	UnknowHostException
-	 * @throws	IOException
-	 * @throws	TransmissionError
-	 * @throws	ProtocolError
-	 * @throws	VersionError
-	 * @throws	SizeError
-	 * @throws	EmptyDirectory
-	 * @throws	InternalRemoteError
-	 * @throws	ProtocolRemoteError
-	 * @throws	VersionRemoteError
+	/** Getter for tracker socket
 	 */
-	private String[] listDirectory() throws EmptyDirectory, InternalError, UnknownHostException, IOException, TransmissionError, ProtocolError, VersionError, SizeError, InternalRemoteError, ProtocolRemoteError, VersionRemoteError {
-		ProtocolP2PPacketTCP d = new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.LIST_REQUEST));
-		try {
-			d.sendRequest((Object)hostList.get(0).getTCPSocket());
-			Payload p = d.receiveResponse().getPayload();
-			assert p instanceof FileList : "This payload must be instance of Filelist";
-			if (!(p instanceof FileList)) {
-				throw new InternalError();
-			} else {
-				return ((FileList)p).getFileList();
-			}
-		} catch (NotFound e) {
-			throw new ProtocolError();
-		} catch (EmptyFile e) {
-			throw new ProtocolError();
-		} catch (SocketClosed e){
-			System.err.println("listDirectory : SocketClosed");
-			throw new ProtocolError();
-		}
+	protected Object getTrackerSocket() {
+		return (Object)tracker.getTCPSocket();
 	}
 
-	/** Compute Hashsum of a file.
-	 * @param	filename
-	 * @return	hashsum
+	/** Getter for HostItem socket
+	 * @param hostItem	HostItem
 	 */
-	private byte[] computeHashsum(String filename, HashAlgorithm h) {
-		try {
-			MessageDigest md = MessageDigest.getInstance(HashAlgorithm.SHA512.getName());
-			return md.digest(Files.readAllBytes(Paths.get(baseDirectory + filename)));
-		} catch (NoSuchAlgorithmException e) {
-			System.out.println("Error: " + h.getName() + " not supported");
-		} catch (IOException e) {
-			System.out.println("Error: cannot read " + filename);
-		}
-		return new byte[0];
+	protected Object getHostItemSocket(HostItem hostItem) {
+		return (Object)hostItem.getTCPSocket();
 	}
 }

src/clientP2P/ClientManagementUDP.java

@@ -1,38 +1,14 @@
 package clientP2P;
-import exception.InternalError;
-import exception.ProtocolError;
-import exception.SizeError;
-import exception.TransmissionError;
-import exception.VersionError;
-import remoteException.EmptyFile;
-import remoteException.EmptyDirectory;
-import remoteException.InternalRemoteError;
-import remoteException.NotFound;
-import remoteException.ProtocolRemoteError;
-import remoteException.VersionRemoteError;
-import java.net.UnknownHostException;
+
 import java.util.Scanner;
-import java.net.DatagramSocket;
-import java.io.IOException;
-import java.nio.file.Files;
-import java.io.File;
-import java.nio.file.Paths;
-import java.nio.file.StandardOpenOption;
-import java.util.Arrays;
-import java.util.List;
-import tools.HostItem;
-import protocolP2P.ProtocolP2PPacketUDP;
 import protocolP2P.Payload;
-import protocolP2P.RequestResponseCode;
-import protocolP2P.FileList;
-import protocolP2P.FilePart;
-import protocolP2P.LoadRequest;
-import protocolP2P.HashAlgorithm;
-import protocolP2P.HashRequest;
-import protocolP2P.HashResponse;
-import java.security.MessageDigest;
-import java.security.NoSuchAlgorithmException;
+import protocolP2P.ProtocolP2PPacket;
+import protocolP2P.ProtocolP2PPacketUDP;
+import tools.HostItem;
+import tools.Logger;
+import tools.LogLevel;
 import clientP2P.ClientDownloadUDP;
+import clientP2P.ClientManagement;
 
 /** Implementation of P2P-JAVA-PROJECT CLIENT
  * @author	Louis Royer
@@ -40,157 +16,65 @@ import clientP2P.ClientDownloadUDP;
  * @author	JS Auge
  * @version	1.0
  */
-public class ClientManagementUDP implements Runnable {
-	private String baseDirectory;
-	private String partsSubdir;
-	private List<HostItem> hostList;
-
-	/** Constructor for UDP implementation, with baseDirectory and UDPPort parameters.
+public class ClientManagementUDP extends ClientManagement {
+	/** Constructor for UDP implementation, with baseDirectory, tracker, partsSubdir, logger and scanner parameters.
 	 * @param baseDirectory	the root directory where files are stored
-	 * @param host	hostname of the server
-	 * @param UDPPort	the server will listen on this port
+	 * @param tracker	tracker HostItem
+	 * @param partsSubdir	subdirectory to store file parts
+	 * @param logger	Loggger
+	 * @param scanner	Scanner used to read input
+	 */
+	public ClientManagementUDP(String baseDirectory, HostItem tracker, String partsSubdir, Logger logger, Scanner scanner) {
+		super(baseDirectory, tracker, partsSubdir, logger, scanner);
+	}
+
+	/** Initialize downloader
+	 * @param filename	Name of the file to download
+	 */
+	protected void initDownloader(String filename) {
+		downLoader = (ClientDownload) new ClientDownloadUDP(filename, hostList, partsSubdir, baseDirectory, logger);
+	}
+	
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
+	 */
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeUDP(text, logLevel);
+	}
+
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
 	 */
-	public ClientManagementUDP(String baseDirectory, List<HostItem> hostList, String partsSubdir) {
-		this.baseDirectory = baseDirectory;
-		this.hostList = hostList;
-		this.partsSubdir = partsSubdir;
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeUDP(e, logLevel);
 	}
 
-	/** Implementation of Runnable
+	/** Create packets
+	 * @param payload	Payload
 	 */
-	public void run() {
-		try {
-			System.out.println("Enter all servers: type \"stop\" when finished");
-			Scanner scanner = new Scanner(System.in);
-			String[] list = listDirectory();
-			System.out.println("Files present on the server:");
-			for(String listItem: list) {
-				System.out.println(listItem);
-			}
-			System.out.println("Name of the file to download:");
-			String f = scanner.nextLine();
-			download(f);
-			System.out.println("File sucessfully downloaded");
-		} catch (EmptyDirectory e) {
-			System.err.println("Error: Server has no file in directory");
-		} catch (InternalError e) {
-			System.err.println("Error: Client internal error");
-		} catch (UnknownHostException e) {
-			System.err.println("Error: Server host is unknown");
-		} catch (IOException e) {
-			System.err.println("Error: Request cannot be send or response cannot be received");
-		} catch (TransmissionError e) {
-			System.err.println("Error: Message received is too big");
-		} catch (ProtocolError e) {
-			System.err.println("Error: Cannot decode server’s response");
-		} catch (VersionError e) {
-			System.err.println("Error: Server’s response use bad version of the protocol");
-		} catch (SizeError e) {
-			System.err.println("Error: Cannot handle this packets because of internal representation limitations of numbers on the client");
-		} catch (InternalRemoteError e) {
-			System.err.println("Error: Server internal error");
-		} catch (ProtocolRemoteError e) {
-			System.err.println("Error: Server cannot decode client’s request");
-		} catch (VersionRemoteError e) {
-			System.err.println("Error: Server cannot decode this version of the protocol");
-		} catch (NotFound e) {
-			System.err.println("Error: Server has not this file in directory");
-		} catch (EmptyFile e) {
-			System.err.println("Error: File is empty");
-		}
+	protected < T extends Payload > ProtocolP2PPacket<T> createProtocolP2PPacket(T payload) {
+		return (ProtocolP2PPacket<T>)new ProtocolP2PPacketUDP<T>(payload);
 	}
 
-	/** Try to download a file
-	 * @param filename	name of the file to download
-	 * @throws	NotFound
-	 * @throws	InternalError
-	 * @throws	UnknownHostException
-	 * @throws	IOException
-	 * @throws	TransmissionError
-	 * @throws	ProtocolError
-	 * @throws	VersionError
-	 * @throws	SizeError
-	 * @throws	InternalRemoteError
-	 * @throws	ProtocolRemoteError
-	 * @throws	VersionRemoteError
-	 * @throws	EmptyFile
+	/** Getter for tracker socket
 	 */
-	private void download(String filename) throws EmptyFile, NotFound, InternalError, UnknownHostException, IOException, TransmissionError, ProtocolError, VersionError, SizeError, InternalRemoteError, ProtocolRemoteError, VersionRemoteError {
-		ClientDownloadUDP downLoader = new ClientDownloadUDP(filename, hostList, partsSubdir, baseDirectory);
-		Thread t = new Thread(downLoader);
-		t.start();
-		try {
-			t.join();
-			if (downLoader.getSuccess()) {
-				byte[] hash512 = downLoader.getHashSum512();
-				if (!Arrays.equals(hash512, computeHashsum(filename, HashAlgorithm.SHA512))) {
-					System.err.println("Error: Hashsum does not match");
-					System.err.println("Computed checksum:");
-					byte[] c = computeHashsum(filename, HashAlgorithm.SHA512);
-					for (byte b: c) {
-						System.err.print(String.format("%02X", b));
-					}
-					System.err.println("");
-					System.err.println("Received checksum:");
-					for (byte b: hash512) {
-						System.err.print(String.format("%02X", b));
-					}
-					System.err.println("");
-					throw new InternalError();
-				}
-			} else {
-				throw new InternalError();
-			}
-		} catch (InterruptedException e) {
-			throw new InternalError();
-		}
+	protected Object getTrackerSocket() {
+		return (Object)tracker.getUDPSocket();
 	}
 
-	/** list server’s directory content
-	 * @return	list of files
-	 * @throws	InternalError
-	 * @throws	UnknowHostException
-	 * @throws	IOException
-	 * @throws	TransmissionError
-	 * @throws	ProtocolError
-	 * @throws	VersionError
-	 * @throws	SizeError
-	 * @throws	EmptyDirectory
-	 * @throws	InternalRemoteError
-	 * @throws	ProtocolRemoteError
-	 * @throws	VersionRemoteError
+	/** Getter for HostItem socket
+	 * @param hostItem	HostItem
 	 */
-	private String[] listDirectory() throws EmptyDirectory, InternalError, UnknownHostException, IOException, TransmissionError, ProtocolError, VersionError, SizeError, InternalRemoteError, ProtocolRemoteError, VersionRemoteError {
-		ProtocolP2PPacketUDP d = new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.LIST_REQUEST));
-		d.sendRequest((Object)hostList.get(0).getUDPSocket());
-		try {
-			Payload p = d.receiveResponse().getPayload();
-			assert p instanceof FileList : "This payload must be instance of Filelist";
-			if (!(p instanceof FileList)) {
-				throw new InternalError();
-			} else {
-				return ((FileList)p).getFileList();
-			}
-		} catch (NotFound e) {
-			throw new ProtocolError();
-		} catch (EmptyFile e) {
-			throw new ProtocolError();
-		}
+	protected Object getHostItemSocket(HostItem hostItem) {
+		return (Object)hostItem.getUDPSocket();
 	}
 
-	/** Compute Hashsum of a file.
-	 * @param	filename
-	 * @return	hashsum
+	/** Close HostItem socket
+	 * @param hostItem	HostItem
 	 */
-	private byte[] computeHashsum(String filename, HashAlgorithm h) {
-		try {
-			MessageDigest md = MessageDigest.getInstance(HashAlgorithm.SHA512.getName());
-			return md.digest(Files.readAllBytes(Paths.get(baseDirectory + filename)));
-		} catch (NoSuchAlgorithmException e) {
-			System.out.println("Error: " + h.getName() + " not supported");
-		} catch (IOException e) {
-			System.out.println("Error: cannot read " + filename);
-		}
-		return new byte[0];
+	protected void closeHostItemSocket(HostItem hostItem) {
+		hostItem.closeUDPSocket();
 	}
 }

src/clientP2P/ClientP2P.java

@@ -1,16 +1,19 @@
 package clientP2P;
+
+import java.util.Scanner;
+import java.util.List;
 import clientP2P.ClientManagementUDP;
 import clientP2P.ClientManagementTCP;
+
 import serverP2P.ServerManagementUDP;
 import serverP2P.ServerManagementTCP;
-import tools.Directories;
 import tools.Logger;
 import tools.LogLevel;
 import tools.Directories;
-import java.util.Scanner;
-import java.util.List;
 import tools.HostItem;
-import tools.HostList;
+import tools.ServerPortRange;
+import tools.TrackerPortRange;
+
 
 /** Client + Server implementation.
  * @author	Louis Royer
@@ -18,106 +21,181 @@ import tools.HostList;
  * @author	JS Auge
  * @version	1.0
  */
+
 public class ClientP2P {
-	static private final String subdir = "seeded/";
-	static private String parts = ".parts";
-	private Logger logger;
-	private String host;
-	private int port;
+	private String logDir = "logs/";
+	private String partsDir = ".parts/";
+	private Logger loggerServer;
+	private Logger loggerClient;
 	private Directories directories;
-	private List<HostItem> hostList;
-	private static final int defaultPort = 20000;
-
-
-	/** Initialize logger if directories and logger are null,
+	private HostItem tracker;
+	private HostItem server;
+	private Scanner scanner;
+	
+	/** Initialize loggers if directories and logger are null,
 	 * else fail silently.
 	 */
-	public void initLogger() {
-		if (directories == null && logger == null) {
-			directories = new Directories("P2P_JAVA_PROJECT" + port);
-			logger = new Logger(directories.getDataHomeDirectory() + "server.log");
+	public void initDirectoriesAndLoggers() {
+		if (directories == null && loggerServer == null && loggerClient == null) {
+			directories = new Directories("P2P_JAVA_PROJECT_" + server.getPort());
+			directories.createSubdir(logDir);
+			loggerServer = new Logger(directories.getDataHomeDirectory() + logDir + "server.log");
+			loggerClient = new Logger(directories.getDataHomeDirectory() + logDir + "client.log");
+			directories.createSubdir(partsDir);
 		}
 	}
 
-	/** Constructor with portStr as parameter.
-	 * @param portStr	String containing port for server listenning.
+	/** Constructor.
+	 * @param hostnameServer	hostname to bind
+	 * @param portServer	port to bind
+	 * @param hostnameTracker	hostname of tracker
+	 * @param portTracker	port of tracker 
 	 */
-	public ClientP2P(String portStr) {
-		try{
-			port = Integer.valueOf(Integer.parseInt(portStr));
-		} catch (NumberFormatException e){
-			int oldPort = port;
-			port = defaultPort;
-			initLogger();
-			System.err.println("Error incorrect port " + oldPort + " using default port " + defaultPort);
-			logger.write("incorrect port " + oldPort + " using default port " + defaultPort, LogLevel.Info);
-		}
-		initLogger();
-		directories.createSubdir(subdir);
-		directories.createSubdir(parts);
-		host = "localhost";
-		System.out.println("Server will listen on port " + port + " and serve files from " + directories.getDataHomeDirectory() + subdir);
-		directories.askOpenDataHomeDirectory(subdir);
-		System.out.println("Please enter list of servers to use; first one will be used to ask list of files");
+	public ClientP2P(String hostnameServer, int portServer, String hostnameTracker, int portTracker) {
+		scanner = new Scanner(System.in);
+		server = new HostItem(hostnameServer, portServer);
+		tracker = new HostItem(hostnameTracker, portTracker);
+		initDirectoriesAndLoggers();
+		System.out.println("Server will listen on port " + portServer + " and serve files from " + directories.getDataHomeDirectory());
+		directories.askOpenDataHomeDirectory(null, scanner);
+	}
+
+	/** Print cli usage
+	 * @param serverPortRange range of server ports
+	 * @param trackerPortRange range of tracker ports
+	 */
+	private static void printUsage(ServerPortRange serverPortRange, TrackerPortRange trackerPortRange) {
+		System.out.println("usage :");
+		System.out.println("\tjava clientP2P.ClientP2P");
+		System.out.println("or");
+		System.out.println("java clientP2P.ClientP2P -- " +
+			"<clientTransportProtocol> " +
+			"<integratedServerHOSTNAME> <integratedServerPORT> " +
+			"<trackerHOSTNAME> <trackerPORT> ");
+		System.out.println("(" + trackerPortRange + " and " + serverPortRange +")");
 	}
 
 	/** Main program entry point.
 	 * 1rst parameter is optionnal, and is used to
 	 * define port used by the server module to listen. If not provided, default to another port.
 	 * @param args	server listenning port
-	 */ 
+	 */
 	public static void main(String [] args) {
-		ClientP2P c;
-		try {
-			c = new ClientP2P(args[1]);
-		} catch (IndexOutOfBoundsException e){
-			c = new ClientP2P("" + defaultPort);
+		final String defaultHostname = "localhost";
+		String hostnameServer = "";
+		int portServer = 0;
+		String hostnameTracker = "";
+		int portTracker = 0;
+		String protocolClient = "";
+		Scanner scanner = new Scanner(System.in);
+		final ServerPortRange serverPortRange = new ServerPortRange();
+		final TrackerPortRange trackerPortRange = new TrackerPortRange();
+
+		if ((args.length != 6) && (args.length != 0)){
+			ClientP2P.printUsage(serverPortRange, trackerPortRange);
+			System.exit(1);
+		}
+		else if(args.length == 6){
+				protocolClient = args[1];
+				hostnameServer = args[2];
+				portServer = Integer.valueOf(Integer.parseInt(args[3]));
+				hostnameTracker = args[4];
+				portTracker = Integer.valueOf(Integer.parseInt(args[5]));
+		} else{
+			System.out.println("Client, wich transport protocol do you want to use (default = TCP): ");
+			protocolClient = scanner.nextLine();
+			System.out.println("server side, enter hostname to bind (default = localhost): ");
+			hostnameServer = scanner.nextLine();
+			if(hostnameServer.equals("")){
+				hostnameServer = defaultHostname;
+				System.out.println("using default hostname : " + hostnameServer);
+			}
+			System.out.println("enter port (default = " + serverPortRange.getDefaultPort() +"): ");
+			String portServerStr = scanner.nextLine();
+			if(portServerStr.equals("")){
+				portServer = serverPortRange.getDefaultPort();
+				System.out.println("using default port : " + portServer);
+			} else {
+				portServer = Integer.valueOf(Integer.parseInt(portServerStr));
+			}
+			System.out.println("enter hostname of tracker (default = localhost): ");
+			hostnameTracker = scanner.nextLine();
+			if(hostnameTracker.equals("")){
+				hostnameTracker = defaultHostname;
+				System.out.println("tracker default hostname : " + hostnameTracker);
+			}
+			System.out.println("enter tracker's port (default = "+trackerPortRange.getDefaultPort() + "): ");
+			String portTrackerStr = scanner.nextLine();
+			if(portTrackerStr.equals("")){
+				portTracker = trackerPortRange.getDefaultPort();
+				System.out.println("using default port : " + portTracker);
+			} else {
+				portTracker = Integer.valueOf(Integer.parseInt(portTrackerStr));
+			}
+		}
+
+		System.out.println("using hostname : " + hostnameServer);
+		if(serverPortRange.isPortInRange(portServer)){
+			System.out.println("using port : " + portServer);
+		}
+		else {
+			System.out.println("Port not in range. " + serverPortRange);
+			portServer = serverPortRange.getDefaultPort();
 		}
+		System.out.println("tracker hostname : " + hostnameTracker);
 
-		// Server threads
-		ServerManagementUDP smudp = new ServerManagementUDP(c.directories.getDataHomeDirectory() + subdir, c.port, c.logger);
-		ServerManagementTCP smtcp = new ServerManagementTCP(c.directories.getDataHomeDirectory() + subdir, c.port, c.logger);
+		if(trackerPortRange.isPortInRange(portTracker)){
+			System.out.println("using port : " + portTracker);
+		}
+		else {
+			System.out.println("Port not in range. " + trackerPortRange);
+			portTracker = trackerPortRange.getDefaultPort();
+		}
+
+		ClientP2P c = new ClientP2P(hostnameServer, portServer, hostnameTracker, portTracker);
+
+		ServerManagementUDP smudp = new ServerManagementUDP(c.directories.getDataHomeDirectory(), c.server, c.tracker, c.loggerServer);
+		ServerManagementTCP smtcp = new ServerManagementTCP(c.directories.getDataHomeDirectory(), c.server, c.tracker, c.loggerServer);
 		Thread tudp = new Thread(smudp);
-		tudp.setName("server UDP P2P-JAVA-PROJECT (port: " + c.port + ")");
+		tudp.setName("server UDP P2P-JAVA-PROJECT");
 		tudp.start();
 		Thread ttcp = new Thread(smtcp);
-		ttcp.setName("server TCP P2P-JAVA-PROJECT (port: " + c.port + ")");
+		ttcp.setName("server TCP P2P-JAVA-PROJECT");
 		ttcp.start();
 
 		// Wait a bit before printing client interface
 		// This is not required, but allow to have a cleaner interface
 		try {
-			Thread.sleep(100);
+			Thread.sleep(200);
 		} catch(InterruptedException e) {
 			Thread.currentThread().interrupt();
 		}
 
-		// initialize Host lists
-		c.hostList = HostList.getServList();
-		System.out.println("Client : Which transport protocol do you want to use? [TCP/udp]");
-		Scanner sc = new Scanner(System.in);
-		String transportchoosen = sc.nextLine();
-		Thread t;
-		switch(transportchoosen){
+		Thread tclient;
+		switch(protocolClient){
 			case "UDP":
 			case "udp":
-			case "upd": // alias typo
+			case "upd": // to avoid users typos
 			case "2" :
 				System.out.println("Starting with UDP");
-				ClientManagementUDP cmudp = new ClientManagementUDP(c.directories.getDataHomeDirectory(), c.hostList, c.directories.getDataHomeDirectory() + c.parts + "/");
-				t = new Thread(cmudp);
+				ClientManagementUDP cmudp = new ClientManagementUDP(c.directories.getDataHomeDirectory(), c.tracker, c.directories.getDataHomeDirectory() + c.partsDir, c.loggerClient, c.scanner);
+				tclient = new Thread(cmudp);
 				break;
 			case "TCP":
 			case "tcp":
 			case "1":
 			default:
 				System.out.println("Starting with TCP");
-				ClientManagementTCP cmtcp = new ClientManagementTCP(c.directories.getDataHomeDirectory(), c.hostList, c.directories.getDataHomeDirectory() + c.parts + "/");
-				t = new Thread(cmtcp);
+				ClientManagementTCP cmtcp = new ClientManagementTCP(c.directories.getDataHomeDirectory(), c.tracker, c.directories.getDataHomeDirectory() + c.partsDir, c.loggerClient, c.scanner);
+				tclient = new Thread(cmtcp);
 				break;
-		  }
-
-		t.setName("client P2P-JAVA-PROJECT");
-		t.start();
+		}
+		tclient.setName("client P2P-JAVA-PROJECT");
+		tclient.start();
+		try {
+			tclient.join();
+		} catch (InterruptedException e) {}
+		smudp.setStop();
+		smtcp.setStop();
 	}
 }

src/exception/LocalException.java

@@ -1,4 +1,5 @@
 package exception;
-public class InternalError extends Exception {
+
+public abstract class LocalException extends Exception {
 	private static final long serialVersionUID = 12L;
 }

src/exception/RemoteException.java

@@ -1,4 +1,5 @@
 package exception;
-public class ProtocolError extends Exception {
+
+public abstract class RemoteException extends Exception {
 	private static final long serialVersionUID = 12L;
 }

src/exception/SocketClosed.java

@@ -1,4 +0,0 @@
-package exception;
-public class SocketClosed extends Exception {
-	private static final long serialVersionUID = 12L;
-}

src/exception/TransmissionError.java

@@ -1,4 +0,0 @@
-package exception;
-public class TransmissionError extends Exception {
-	private static final long serialVersionUID = 12L;
-}

src/exception/VersionError.java

@@ -1,4 +0,0 @@
-package exception;
-public class VersionError extends Exception {
-	private static final long serialVersionUID = 12L;
-}

src/localException/InternalError.java

@@ -0,0 +1,7 @@
+package localException;
+
+import exception.LocalException;
+
+public class InternalError extends LocalException {
+	private static final long serialVersionUID = 12L;
+}

src/localException/ProtocolError.java

@@ -0,0 +1,7 @@
+package localException;
+
+import exception.LocalException;
+
+public class ProtocolError extends LocalException {
+	private static final long serialVersionUID = 12L;
+}

src/localException/SizeError.java

@@ -1,5 +1,9 @@
-package exception;
+package localException;
+
+import exception.LocalException;
+
+
 /** Used on reception side when size as set in Packet is too big, and we cant store this in a int/long as usual. */
-public class SizeError extends Exception {
+public class SizeError extends LocalException {
 	private static final long serialVersionUID = 12L;
 }

src/localException/SocketClosed.java

@@ -0,0 +1,7 @@
+package localException;
+
+import exception.LocalException;
+
+public class SocketClosed extends LocalException {
+	private static final long serialVersionUID = 12L;
+}

src/localException/TransmissionError.java

@@ -0,0 +1,7 @@
+package localException;
+
+import exception.LocalException;
+
+public class TransmissionError extends LocalException {
+	private static final long serialVersionUID = 12L;
+}

src/localException/VersionError.java

@@ -0,0 +1,7 @@
+package localException;
+
+import exception.LocalException;
+
+public class VersionError extends LocalException {
+	private static final long serialVersionUID = 12L;
+}

src/protocolP2P/CodeType.java

@@ -8,6 +8,7 @@ package protocolP2P;
  */
 public enum CodeType {
 	REQUEST,
+	REQUEST_TRACKER,
 	RESPONSE,
 	ERROR
 }

src/protocolP2P/DiscoverRequest.java

@@ -0,0 +1,71 @@
+package protocolP2P;
+import protocolP2P.Payload;
+import tools.BytesArrayTools;
+import localException.InternalError;
+import localException.SizeError;
+import localException.ProtocolError;
+import localException.TransmissionError;
+
+/** Representation of payload for discover request.
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public class DiscoverRequest extends Payload {
+
+	private String filename; 
+
+	/** Constructor with filename (typically used by client). If filename is null, it is initialized with "".
+	 * @param filename	Name of the file you want a server list of.
+	 * @throws	InternalError
+	 */
+	public DiscoverRequest(String filename) throws InternalError {
+		super(RequestResponseCode.DISCOVER_REQUEST);
+		if (filename == null) {
+			this.filename = "";
+		} else {
+			this.filename = filename;
+		}
+	}
+
+	/** Constructor (typically used by server) with a byte[] parameter containing the Packet received.
+	 * @param packet	the full Packet received
+	 * @throws	SizeError
+	 * @throws	InternalError
+	 * @throws	ProtocolError
+	 * @throws	TransmissionError
+	 */
+	protected DiscoverRequest(byte[] packet) throws SizeError, ProtocolError, InternalError, TransmissionError {
+		super(packet);
+		int size = getPayloadSize(packet);
+		filename = BytesArrayTools.readString(packet, Payload.PAYLOAD_START_POSITION, size);
+	}
+
+	/** Returns a byte[] containing Packet with padding.
+	 * This Packet is still incomplete and should not be send directly.
+	 * ProtocolP2PPacket will use this method to generate the complete Packet.
+	 * @return Packet with padding
+	 * @throws	InternalError
+	 */
+	protected byte[] toPacket() throws InternalError {
+		// compute total size
+		int size = PAYLOAD_START_POSITION + filename.length();
+		byte[] packet = new byte[size + 1]; // java initialize all to zero
+		// set request/response code
+		packet[RequestResponseCode.RRCODE_POSITION] = requestResponseCode.codeValue;
+		// set Payload size
+		setPayloadSize(size - PAYLOAD_START_POSITION, packet);
+		// write filename to Packet
+		BytesArrayTools.write(packet, filename, PAYLOAD_START_POSITION);
+		return packet;
+	}
+
+	/** Filename getter.
+	 * @return	filename
+	 */
+	public String getFilename() {
+		return filename;
+	}
+
+}

src/protocolP2P/DiscoverResponse.java

@@ -0,0 +1,117 @@
+package protocolP2P;
+import protocolP2P.Payload;
+import tools.HostItem;
+import java.util.ArrayList;
+import java.util.List;
+import localException.InternalError;
+import localException.SizeError;
+import localException.ProtocolError;
+import localException.TransmissionError;
+import tools.BytesArrayTools;
+
+/** Representation of payload for discover response.
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public class DiscoverResponse extends Payload {
+
+	private List<HostItem> hostList;
+	private String filename;
+	private static final int FILENAME_SIZE_POSITION = PAYLOAD_START_POSITION;
+	private static final int FILENAME_POSITION = FILENAME_SIZE_POSITION + 4;
+
+	/** Constructor with filename (typically used by tracker). If filename is null, it is initialized with "".
+	 * @param filename	Name of the file related to the server list.
+	 * @param hostList	List of servers
+	 * @throws	InternalError
+	 */
+	public DiscoverResponse(String filename, List<HostItem> hostList) throws InternalError {
+		super(RequestResponseCode.DISCOVER_RESPONSE);
+		this.filename = filename;
+		this.hostList = hostList;
+	}
+
+	/** Constructor (typically used by server) with a byte[] parameter containing the Packet received.
+	 * @param packet	the full Packet received
+	 * @throws	SizeError
+	 * @throws	InternalError
+	 * @throws	ProtocolError
+	 * @throws	TransmissionError
+	 */
+	protected DiscoverResponse(byte[] packet) throws SizeError, ProtocolError, InternalError, TransmissionError {
+		super(packet);
+		int size = getPayloadSize(packet);
+		/* Read filename size */
+		int filenameSize = BytesArrayTools.readInt(packet, FILENAME_SIZE_POSITION);
+
+		/* Read filename */
+		filename = BytesArrayTools.readString(packet, FILENAME_POSITION, filenameSize);
+
+		// TODO
+		hostList = new ArrayList<>();
+		int i = FILENAME_POSITION + filenameSize;
+		while(i<size) {
+			int port = BytesArrayTools.readInt16Bits(packet, i);
+			i += 2;
+			String hostname = BytesArrayTools.readString(packet, i, "\n");
+			i += hostname.length();
+			hostList.add(new HostItem(hostname, port));
+		}
+	}
+
+	/** Returns a byte[] containing Packet with padding.
+	 * This Packet is still incomplete and should not be send directly.
+	 * ProtocolP2PPacket will use this method to generate the complete Packet.
+	 * @return Packet with padding
+	 * @throws	InternalError
+	 */
+	protected byte[] toPacket() throws InternalError {
+		int filenameSize = filename.length();
+		int hostListSize = 0;
+		for (HostItem hostItem: hostList) {
+			hostListSize += (2 + hostItem.getHostname().length() + 1);
+		} 
+		// compute total size
+		int size = FILENAME_POSITION + filename.length() + hostListSize;
+		byte[] packet = new byte[size + 1]; // java initialize all to zero
+		// set request/response code
+		packet[RequestResponseCode.RRCODE_POSITION] = requestResponseCode.codeValue;
+		// set Payload size
+		setPayloadSize(size - PAYLOAD_START_POSITION, packet);
+		// write filename size
+		BytesArrayTools.write(packet, FILENAME_SIZE_POSITION, filenameSize);
+		// write filename
+		BytesArrayTools.write(packet, filename, FILENAME_POSITION);
+
+		int i = FILENAME_POSITION + filename.length();
+		// write hostList
+		for(HostItem hostItem: hostList) {
+			try {
+				BytesArrayTools.write16Bits(packet, i, hostItem.getPort());
+				i+=2;
+				String hostname = hostItem.getHostname() + "\n";
+				BytesArrayTools.write(packet, hostname, i);
+				i+=hostname.length();
+			} catch (SizeError e) {
+				throw new InternalError();
+			}
+		}
+		return packet;
+	}
+
+	/** HostList getter.
+	 * @return	hostList
+	 */
+	public List<HostItem> getHostList() {
+		return hostList;
+	}
+
+	/** Filename getter.
+	 * @return	filename
+	 */
+	public String getFilename() {
+		return filename;
+	}
+}

src/protocolP2P/FileList.java

@@ -1,12 +1,10 @@
 package protocolP2P;
-import java.util.Arrays;
 import protocolP2P.Payload;
 import protocolP2P.RequestResponseCode;
-import exception.TransmissionError;
-import exception.ProtocolError;
-import exception.InternalError;
-import exception.SizeError;
-import java.io.UnsupportedEncodingException;
+import localException.TransmissionError;
+import localException.ProtocolError;
+import localException.InternalError;
+import localException.SizeError;
 import tools.BytesArrayTools;
 
 /** Representation of payload for list response.

src/protocolP2P/FilePart.java

@@ -1,13 +1,11 @@
 package protocolP2P;
 import protocolP2P.Payload;
 import protocolP2P.RequestResponseCode;
-import exception.ProtocolError;
-import exception.InternalError;
-import exception.SizeError;
-import exception.TransmissionError;
+import localException.ProtocolError;
+import localException.InternalError;
+import localException.SizeError;
+import localException.TransmissionError;
 import tools.BytesArrayTools;
-import java.util.Arrays;
-import java.io.UnsupportedEncodingException;
 
 /** Representation of payload for load response.
  * @author	Louis Royer
@@ -36,7 +34,7 @@ public class FilePart extends Payload {
 		super(RequestResponseCode.LOAD_RESPONSE);
 		/* asserts to help debugging */
 		assert totalSize >= 0 : "totalSize cannot be negative";
-		assert partialContent.length != 0 : "partialContent.length cannot be zero, see RRCode.EMPTY_FILE"; 
+		assert partialContent.length != 0 : "partialContent.length cannot be zero, see RRCode.EMPTY_FILE";
 		assert totalSize >= partialContent.length : "totalSize must be greater than partialContent.length";
 		assert offset >= 0 : "offset cannot be negative";
 		assert filename != null : "filename is required";
@@ -83,7 +81,7 @@ public class FilePart extends Payload {
 		// set request/response code
 		packet[RequestResponseCode.RRCODE_POSITION] = requestResponseCode.codeValue;
 		// set Payload size
-		setPayloadSize(size - OFFSET_POSITION, packet);
+		setPayloadSize(size - PAYLOAD_START_POSITION, packet);
 		// write offset to Packet
 		BytesArrayTools.write(packet, OFFSET_POSITION, offset);
 		// write totalSize to Packet

src/protocolP2P/HashRequest.java

@@ -1,11 +1,10 @@
 package protocolP2P;
 import protocolP2P.Payload;
 import protocolP2P.HashAlgorithm;
-import java.io.UnsupportedEncodingException;
-import exception.TransmissionError;
-import exception.SizeError;
-import exception.ProtocolError;
-import exception.InternalError;
+import localException.TransmissionError;
+import localException.SizeError;
+import localException.ProtocolError;
+import localException.InternalError;
 import tools.BytesArrayTools;
 
 
@@ -21,12 +20,12 @@ public class HashRequest extends Payload {
 	private HashAlgorithm[] algoList;
 	private static final int FILENAME_SIZE_POSITION = PAYLOAD_START_POSITION;
 	private static final int FILENAME_POSITION = FILENAME_SIZE_POSITION + 4;
-	
+
 	/** Constructor (typically used by the server) with a filename parameter.
 	 * @param filename	name of the file to download. Must not be empty.
 	 * @param algoList	List of hash algorithms used
 	 * @throws	InternalError
-	 * 
+	 *
 	 */
 	public HashRequest(String filename, HashAlgorithm[] algoList) throws InternalError {
 		super(RequestResponseCode.HASH_REQUEST);

src/protocolP2P/HashResponse.java

@@ -2,11 +2,10 @@ package protocolP2P;
 import protocolP2P.Payload;
 import java.util.HashMap;
 import java.util.Map;
-import java.io.UnsupportedEncodingException;
-import exception.TransmissionError;
-import exception.SizeError;
-import exception.ProtocolError;
-import exception.InternalError;
+import localException.TransmissionError;
+import localException.SizeError;
+import localException.ProtocolError;
+import localException.InternalError;
 import tools.BytesArrayTools;
 
 
@@ -22,12 +21,12 @@ public class HashResponse extends Payload {
 	private Map<HashAlgorithm, byte[]> hashes = new HashMap<>();
 	private static final int FILENAME_SIZE_POSITION = PAYLOAD_START_POSITION;
 	private static final int FILENAME_POSITION = FILENAME_SIZE_POSITION + 4;
-	
+
 	/** Constructor (typically used by the server) with a filename parameter.
 	 * @param filename	name of the file to download. Must not be empty.
 	 * @param hashes	HashMap containing hashes for file.
 	 * @throws	InternalError
-	 * 
+	 *
 	 */
 	public HashResponse(String filename, Map<HashAlgorithm, byte[]> hashes) throws InternalError {
 		super(RequestResponseCode.HASH_RESPONSE);
@@ -80,7 +79,7 @@ public class HashResponse extends Payload {
 			}
 			start += hashSize;
 		} while (start < size);
-			
+
 	}
 
 	/** Returns a byte[] containing Packet with padding.
@@ -100,7 +99,7 @@ public class HashResponse extends Payload {
 			size += 4 + s.length;
 		}
 		byte[] packet = new byte[size + 1]; // java initialize all to zero
-		
+
 		// set request/response code
 		packet[RequestResponseCode.RRCODE_POSITION] = requestResponseCode.codeValue;
 		// set Payload size
@@ -112,14 +111,14 @@ public class HashResponse extends Payload {
 		int bCount = FILENAME_POSITION + filename.length();
 		for(HashAlgorithm h : hashes.keySet()) {
 			String s = h.getName();
-			BytesArrayTools.write(packet, bCount, (int)s.length());
+			BytesArrayTools.write(packet, bCount, s.length());
 			bCount += 4;
 			// write algoname
 			BytesArrayTools.write(packet, s, bCount);
 			bCount += s.length();
 			// write hash size
 			byte[] hashb = hashes.get(HashAlgorithm.fromName(s));
-			BytesArrayTools.write(packet, bCount, (int)hashb.length);
+			BytesArrayTools.write(packet, bCount, hashb.length);
 			bCount += 4;
 			if (hashb.length != 0) {
 				// write hash

src/protocolP2P/LoadRequest.java

@@ -1,12 +1,11 @@
 package protocolP2P;
 import protocolP2P.Payload;
 import protocolP2P.RequestResponseCode;
-import exception.TransmissionError;
-import exception.ProtocolError;
-import exception.InternalError;
-import exception.SizeError;
+import localException.TransmissionError;
+import localException.ProtocolError;
+import localException.InternalError;
+import localException.SizeError;
 import tools.BytesArrayTools;
-import java.io.UnsupportedEncodingException;
 
 /** Representation of payload for load request.
  * @author	Louis Royer
@@ -61,7 +60,7 @@ public class LoadRequest extends Payload {
 
 		/* Read maxSizePartialContent */
 		maxSizePartialContent = BytesArrayTools.readLong(packet, MAX_SIZE_PARTIAL_CONTENT_POSITION);
-		
+
 		/* Read filename */
 		int size = BytesArrayTools.readInt(packet, FILENAME_SIZE_POSITION);
 		filename = BytesArrayTools.readString(packet, FILENAME_POSITION, size);
@@ -83,11 +82,11 @@ public class LoadRequest extends Payload {
 		// set Payload size
 		setPayloadSize(size - OFFSET_POSITION, packet);
 		// Write offset
-		BytesArrayTools.write(packet, OFFSET_POSITION, (long)offset);
+		BytesArrayTools.write(packet, OFFSET_POSITION, offset);
 		// Write maxSizePartialContent
-		BytesArrayTools.write(packet, MAX_SIZE_PARTIAL_CONTENT_POSITION, (long)maxSizePartialContent);
+		BytesArrayTools.write(packet, MAX_SIZE_PARTIAL_CONTENT_POSITION, maxSizePartialContent);
 		// Write filenameSize
-		BytesArrayTools.write(packet, FILENAME_SIZE_POSITION, (int)filenameSize);
+		BytesArrayTools.write(packet, FILENAME_SIZE_POSITION, filenameSize);
 		// Write filename
 		BytesArrayTools.write(packet, filename, FILENAME_POSITION);
 		return packet;

src/protocolP2P/Payload.java

@@ -5,10 +5,14 @@ import protocolP2P.FileList;
 import protocolP2P.LoadRequest;
 import protocolP2P.HashRequest;
 import protocolP2P.HashResponse;
-import exception.ProtocolError;
-import exception.InternalError;
-import exception.TransmissionError;
-import exception.SizeError;
+import protocolP2P.DiscoverRequest;
+import protocolP2P.DiscoverResponse;
+import protocolP2P.Register;
+import protocolP2P.Unregister;
+import localException.ProtocolError;
+import localException.InternalError;
+import localException.TransmissionError;
+import localException.SizeError;
 import tools.BytesArrayTools;
 /** Representation of payload. If payload has a size, use subclasses instead.
  * @author	Louis Royer
@@ -27,11 +31,15 @@ public class Payload {
 	 */
 	public Payload(RequestResponseCode requestResponseCode) throws InternalError {
 		/* asserts to help debugging */
-		assert requestResponseCode != RequestResponseCode.LIST_RESPONSE || (this instanceof FileList) : "LIST_RESPONSE must use FilePart class";
-		assert requestResponseCode != RequestResponseCode.LOAD_RESPONSE || (this instanceof FilePart) : "LOAD_RESPONSE must use FileList class";
-		assert requestResponseCode != RequestResponseCode.LOAD_REQUEST  || (this instanceof LoadRequest) : "LOAD_REQUEST must use LoadRequest class";
-		assert requestResponseCode != RequestResponseCode.HASH_REQUEST  || (this instanceof HashRequest) : "HASH_REQUEST must use HashRequest class";
-		assert requestResponseCode != RequestResponseCode.HASH_RESPONSE  || (this instanceof HashResponse) : "HASH_RESPONSE must use HashResponse class";
+		assert requestResponseCode != RequestResponseCode.LIST_RESPONSE     || (this instanceof FileList) : "LIST_RESPONSE must use FilePart class";
+		assert requestResponseCode != RequestResponseCode.LOAD_RESPONSE     || (this instanceof FilePart) : "LOAD_RESPONSE must use FileList class";
+		assert requestResponseCode != RequestResponseCode.LOAD_REQUEST      || (this instanceof LoadRequest) : "LOAD_REQUEST must use LoadRequest class";
+		assert requestResponseCode != RequestResponseCode.HASH_REQUEST      || (this instanceof HashRequest) : "HASH_REQUEST must use HashRequest class";
+		assert requestResponseCode != RequestResponseCode.HASH_RESPONSE     || (this instanceof HashResponse) : "HASH_RESPONSE must use HashResponse class";
+		assert requestResponseCode != RequestResponseCode.DISCOVER_REQUEST  || (this instanceof DiscoverRequest) : "DISCOVER_REQUEST must use DiscoverRequest class";
+		assert requestResponseCode != RequestResponseCode.DISCOVER_RESPONSE || (this instanceof DiscoverResponse) : "DISCOVER_RESPONSE must use DiscoverResponse class";
+		assert requestResponseCode != RequestResponseCode.REGISTER          || (this instanceof Register) : "REGISTER must use Register class";
+		assert requestResponseCode != RequestResponseCode.UNREGISTER        || (this instanceof Unregister) : "UNREGISTER must use Unregister class";
 		this.requestResponseCode = requestResponseCode;
 		checkRequestResponseCode(); // this can throw InternalError
 	}
@@ -46,29 +54,42 @@ public class Payload {
 	 */
 	protected Payload(byte[] packet) throws SizeError, ProtocolError, InternalError, TransmissionError {
 		/* asserts to help debugging */
-		assert getPayloadSize(packet) + 8 <= packet.length : "Payload is truncated";
-		if (packet.length < getPayloadSize(packet) + 8) {
+		assert getPayloadSize(packet) + PAYLOAD_START_POSITION <= packet.length : "Payload is truncated";
+		if (packet.length < getPayloadSize(packet) + PAYLOAD_START_POSITION) {
 			throw new TransmissionError();
 		}
-		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.LIST_RESPONSE || (this instanceof FileList) : "LIST_RESPONSE must use FilePart class";
-		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.LOAD_RESPONSE || (this instanceof FilePart) : "LOAD_RESPONSE must use FileList class";
-		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.LOAD_REQUEST  || (this instanceof LoadRequest) : "LOAD_REQUEST must use LoadRequest class";
+		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.LIST_RESPONSE     || (this instanceof FileList) : "LIST_RESPONSE must use FilePart class";
+		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.LOAD_RESPONSE     || (this instanceof FilePart) : "LOAD_RESPONSE must use FileList class";
+		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.LOAD_REQUEST      || (this instanceof LoadRequest) : "LOAD_REQUEST must use LoadRequest class";
+		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.HASH_REQUEST      || (this instanceof HashRequest) : "HASH_REQUEST must use HashRequest class";
+		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.HASH_RESPONSE     || (this instanceof HashResponse) : "HASH_RESPONSE must use HashResponse class";
+		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.DISCOVER_REQUEST  || (this instanceof DiscoverRequest) : "DISCOVER_REQUEST must use DiscoverRequest class";
+		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.DISCOVER_RESPONSE || (this instanceof DiscoverResponse) : "DISCOVER_RESPONSE must use DiscoverResponse class";
+		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.REGISTER          || (this instanceof Register) : "REGISTER must use Register class";
+		assert RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.UNREGISTER        || (this instanceof Unregister) : "UNREGISTER must use Unregister class";
 		requestResponseCode = RequestResponseCode.fromCode(packet[RequestResponseCode.RRCODE_POSITION]);
 		checkRequestResponseCode(); // this can throw InternalError
 	}
 
 	/** Used to check RRCode used is compatible with this class use, or if a more specific subclass is required.
 	 * @throws	InternalError
-	 */ 
+	 */
 	private void checkRequestResponseCode() throws InternalError {
 		/* Incorrect use cases (use subclasses instead) */
-		if ((requestResponseCode == RequestResponseCode.LIST_RESPONSE && !(this instanceof FileList))
-		 || (requestResponseCode == RequestResponseCode.LOAD_RESPONSE && !(this instanceof FilePart))
-		 || (requestResponseCode == RequestResponseCode.LOAD_REQUEST  && !(this instanceof LoadRequest))) {
+		if ((requestResponseCode == RequestResponseCode.LIST_RESPONSE     && !(this instanceof FileList))
+		 || (requestResponseCode == RequestResponseCode.LOAD_RESPONSE     && !(this instanceof FilePart))
+		 || (requestResponseCode == RequestResponseCode.LOAD_REQUEST      && !(this instanceof LoadRequest))
+		 || (requestResponseCode == RequestResponseCode.HASH_REQUEST      && !(this instanceof HashRequest))
+		 || (requestResponseCode == RequestResponseCode.HASH_RESPONSE     && !(this instanceof HashResponse))
+		 || (requestResponseCode == RequestResponseCode.DISCOVER_REQUEST  && !(this instanceof DiscoverRequest))
+		 || (requestResponseCode == RequestResponseCode.DISCOVER_RESPONSE && !(this instanceof DiscoverResponse))
+		 || (requestResponseCode == RequestResponseCode.REGISTER          && !(this instanceof Register))
+		 || (requestResponseCode == RequestResponseCode.UNREGISTER        && !(this instanceof Unregister))
+		) {
 			throw new InternalError();
 		}
 	}
-	
+
 	/** Returns a byte[] containing Packet with padding.
 	 * This Packet is still incomplete and should not be send directly.
 	 * ProtocolP2PPacket will use this method to generate the complete Packet.
@@ -90,7 +111,7 @@ public class Payload {
 	 * @param size	integer representing payload size
 	 * @param packet	Packet to be completed
 	 * @throws	InternalError
-	 */ 
+	 */
 	protected static void setPayloadSize(int size, byte[] packet) throws InternalError {
 		/* assert to help debugging */
 		assert size >= 0: "Payload size cannot be negative";

src/protocolP2P/ProtocolP2PPacket.java

@@ -1,18 +1,19 @@
 package protocolP2P;
-import exception.InternalError;
-import exception.ProtocolError;
-import exception.SizeError;
-import exception.TransmissionError;
-import exception.VersionError;
-import exception.SocketClosed;
+import localException.InternalError;
+import localException.ProtocolError;
+import localException.SizeError;
+import localException.TransmissionError;
+import localException.VersionError;
+import localException.SocketClosed;
 import remoteException.EmptyDirectory;
 import remoteException.InternalRemoteError;
 import remoteException.NotFound;
 import remoteException.ProtocolRemoteError;
 import remoteException.VersionRemoteError;
 import remoteException.EmptyFile;
-import java.net.InetAddress;
+import remoteException.NotATracker;
 import java.io.IOException;
+import tools.HostItem;
 
 /** Representation of packet.
  * @author	Louis Royer
@@ -20,7 +21,7 @@ import java.io.IOException;
  * @author	JS Auge
  * @version	1.0
  */
-public abstract class ProtocolP2PPacket {
+public abstract class ProtocolP2PPacket < T extends Payload>{
 	private final static byte PROTOCOL_VERSION = 0x12;
 	protected final static int VERSION_POSITION = 0;
 	protected byte version;
@@ -29,9 +30,9 @@ public abstract class ProtocolP2PPacket {
 	/** Constructor with payload parameter (typically used when sending Packet).
 	 * @param payload	the payload associated with the Packet to send
 	 */
-	public ProtocolP2PPacket(Payload payload) {
+	public ProtocolP2PPacket (T payload) {
 		version = PROTOCOL_VERSION;
-		this.payload = payload;
+		this.payload = (Payload)payload;
 	}
 
 	/** Send a request
@@ -48,11 +49,18 @@ public abstract class ProtocolP2PPacket {
 	 * @throws	IOException
 	 * @throws	SocketClosed
 	 */
-	public abstract void sendResponse(ProtocolP2PPacket response) throws InternalError, IOException, SocketClosed;
+	public abstract <U extends ProtocolP2PPacket<?>> void sendResponse(U response) throws InternalError, IOException, SocketClosed;
+
+	/** Get hostItem of the sender
+	 * @return	hostItem of the sender
+	 * @throws	InternalError
+	 */
+	public abstract HostItem getHostItem() throws InternalError;
 
 	/** Receive a response
 	 * @throws	EmptyFile
 	 * @throws	NotFound
+	 * @throws	NotATracker
 	 * @throws	EmptyDirectory
 	 * @throws	InternalRemoteError
 	 * @throws	VersionRemoteError
@@ -65,7 +73,7 @@ public abstract class ProtocolP2PPacket {
 	 * @throws	IOException
 	 * @throws	SocketClosed
 	 */
-	public abstract ProtocolP2PPacket receiveResponse() throws EmptyFile, NotFound, EmptyDirectory, InternalRemoteError, VersionRemoteError, ProtocolRemoteError, TransmissionError, ProtocolError, VersionError, InternalError, SizeError, IOException, SocketClosed;
+	public abstract ProtocolP2PPacket<?> receiveResponse() throws EmptyFile, NotFound, NotATracker, EmptyDirectory, InternalRemoteError, VersionRemoteError, ProtocolRemoteError, TransmissionError, ProtocolError, VersionError, InternalError, SizeError, IOException, SocketClosed;
 
 	/** Receive a request, subclasses must overwrite this constructor.
 	 * @param socket	socket used to get the request
@@ -88,7 +96,7 @@ public abstract class ProtocolP2PPacket {
 	 * @throws	SizeError
 	 */
 	protected ProtocolP2PPacket(byte[] packet) throws TransmissionError, ProtocolError, VersionError, InternalError, SizeError {}
-	
+
 	/** Returns Payload associated with the Packet.
 	 * @return	payload associated with the Packet.
 	 */
@@ -101,6 +109,7 @@ public abstract class ProtocolP2PPacket {
 	 */
 	protected void checkProtocolVersion() throws VersionError {
 		if (PROTOCOL_VERSION != version) {
+			System.err.println("Error: wrong version in packet:" + version);
 			throw new VersionError();
 		}
 	}

src/protocolP2P/ProtocolP2PPacketTCP.java

@@ -1,24 +1,23 @@
 package protocolP2P;
-import exception.InternalError;
-import exception.ProtocolError;
-import exception.SizeError;
-import exception.TransmissionError;
-import exception.VersionError;
-import exception.SocketClosed;
+import localException.InternalError;
+import localException.ProtocolError;
+import localException.SizeError;
+import localException.TransmissionError;
+import localException.VersionError;
+import localException.SocketClosed;
+import remoteException.NotATracker;
 import remoteException.EmptyDirectory;
 import remoteException.InternalRemoteError;
 import remoteException.NotFound;
 import remoteException.ProtocolRemoteError;
 import remoteException.VersionRemoteError;
 import remoteException.EmptyFile;
-import tools.BytesArrayTools;
+import tools.HostItem;
 import protocolP2P.Payload;
 import protocolP2P.RequestResponseCode;
 import protocolP2P.LoadRequest;
 import protocolP2P.FileList;
 import protocolP2P.FilePart;
-import java.util.ArrayList;
-import java.lang.Byte;
 import java.io.IOException;
 import java.io.OutputStream;
 import java.net.Socket;
@@ -29,15 +28,15 @@ import java.net.Socket;
  * @author	JS Auge
  * @version	1.0
  */
-public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
-	
+public class ProtocolP2PPacketTCP < T extends Payload > extends ProtocolP2PPacket < T > {
+
 	private Socket responseSocket; // socket used to recept request and send response
 	private Socket requestSocket; // socket used to send request and to reception response
-	
+
 	/** Constructor with payload parameter (typically used when sending packet).
 	 * @param payload	the payload associated with the packet to send
 	 */
-	public ProtocolP2PPacketTCP(Payload payload) {
+	public ProtocolP2PPacketTCP(T payload) {
 		super(payload);
 	}
 
@@ -67,9 +66,9 @@ public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
 				socket.close();
 			} catch (IOException e2) {
 				System.err.println("Cannot close socket");
-			} finally {
 				throw new SocketClosed();
 			}
+			
 		}
 	}
 
@@ -109,14 +108,16 @@ public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
 		Socket ss = (Socket)socket;
 		byte[] packet = new byte[1024];
 		try {
-			System.err.println("Reading " + ss.getInputStream().read(packet) + " bytes");
+			if (-1 == ss.getInputStream().read(packet)) {
+				throw new IOException();
+			}
 		} catch (IOException e) {
 			// Error: cannot read request, closing socket
 			try {
 				ss.close();
+				throw new SocketClosed();
 			} catch (IOException e2) {
 				System.err.println("Cannot close socket");
-			} finally {
 				throw new SocketClosed();
 			}
 		}
@@ -138,25 +139,27 @@ public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
 				case LOAD_RESPONSE:
 				case LIST_RESPONSE:
 				case HASH_RESPONSE:
+				case DISCOVER_RESPONSE:
+				case NOT_A_TRACKER:
 					// we were expecting a request, but we are receiving a response
 					throw new ProtocolError();
 				default :
 					break;
 			}
 		} catch (TransmissionError e) {
-			(new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss);
+			(new ProtocolP2PPacketTCP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss);
 			throw e;
 		} catch (ProtocolError e) {
-			(new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.PROTOCOL_ERROR))).send(ss);
+			(new ProtocolP2PPacketTCP<Payload>(new Payload(RequestResponseCode.PROTOCOL_ERROR))).send(ss);
 			throw e;
 		} catch (VersionError e) {
-			(new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.VERSION_ERROR))).send(ss);
+			(new ProtocolP2PPacketTCP<Payload>(new Payload(RequestResponseCode.VERSION_ERROR))).send(ss);
 			throw e;
 		} catch (InternalError e) {
-			(new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss);
+			(new ProtocolP2PPacketTCP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss);
 			throw e;
 		} catch (SizeError e) {
-			(new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss);
+			(new ProtocolP2PPacketTCP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss);
 			throw e;
 		}
 		if (protocolError) {
@@ -170,10 +173,10 @@ public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
 	 * @throws	IOException
 	 * @throws	SocketClosed
 	 */
-	public void sendResponse(ProtocolP2PPacket response) throws InternalError, IOException, SocketClosed {
+	public <U extends ProtocolP2PPacket<?>> void sendResponse(U response) throws InternalError, IOException, SocketClosed {
 		assert response instanceof ProtocolP2PPacketTCP: "Wrong Packet type";
 		if (response instanceof ProtocolP2PPacketTCP) {
-			ProtocolP2PPacketTCP r = (ProtocolP2PPacketTCP) response;
+			ProtocolP2PPacketTCP<?> r = (ProtocolP2PPacketTCP<?>) response;
 			assert responseSocket != null : "Cannot send response to a packet not received";
 			if (responseSocket == null) {
 				throw new InternalError();
@@ -188,6 +191,7 @@ public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
 	 * @return	ProtocolP2PPacket received
 	 * @throws	EmptyFile
 	 * @throws	NotFound
+	 * @throws	NotATracker
 	 * @throws	EmptyDirectory
 	 * @throws	InternalRemoteError
 	 * @throws	VersionRemoteError
@@ -200,17 +204,30 @@ public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
 	 * @throws	IOException
 	 * @throws	SocketClosed
 	 */
-	public ProtocolP2PPacket receiveResponse() throws EmptyFile, NotFound, EmptyDirectory, InternalRemoteError, VersionRemoteError, ProtocolRemoteError, TransmissionError, ProtocolError, VersionError, InternalError, SizeError, IOException, SocketClosed {
+	public ProtocolP2PPacket<?> receiveResponse() throws EmptyFile, NotFound, NotATracker, EmptyDirectory, InternalRemoteError, VersionRemoteError, ProtocolRemoteError, TransmissionError, ProtocolError, VersionError, InternalError, SizeError, IOException, SocketClosed {
 		assert requestSocket != null : "Cannot receive response because request packet not sent.";
 		if (requestSocket == null) {
 			throw new InternalError();
 		}
 		// reception
 		byte[] packet = new byte[8192];
-		requestSocket.getInputStream().read(packet);
+		try {
+			if (-1== requestSocket.getInputStream().read(packet)) {
+				throw new IOException();
+			}
+		} catch (IOException e) {
+			// Error: cannot read request, closing socket
+			try {
+				requestSocket.close();
+				throw new SocketClosed();
+			} catch (IOException e2) {
+				System.err.println("Cannot close socket");
+				throw new SocketClosed();
+			}
+		}
 		// contruction
 		try {
-			ProtocolP2PPacketTCP p = new ProtocolP2PPacketTCP(packet);
+			ProtocolP2PPacketTCP<?> p = new ProtocolP2PPacketTCP<>(packet);
 			Payload payload = p.getPayload();
 			switch (payload.getRequestResponseCode()) {
 				case PROTOCOL_ERROR :
@@ -225,23 +242,25 @@ public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
 					throw new NotFound();
 				case EMPTY_FILE:
 					throw new EmptyFile();
+				case NOT_A_TRACKER:
+					throw new NotATracker();
 				default :
 					return (ProtocolP2PPacket)p;
 			}
 		} catch (TransmissionError e) {
-			(new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
+			(new ProtocolP2PPacketTCP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
 			throw e;
 		} catch (ProtocolError e) {
-			(new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.PROTOCOL_ERROR))).send(requestSocket);
+			(new ProtocolP2PPacketTCP<Payload>(new Payload(RequestResponseCode.PROTOCOL_ERROR))).send(requestSocket);
 			throw e;
 		} catch (VersionError e) {
-			(new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.VERSION_ERROR))).send(requestSocket);
+			(new ProtocolP2PPacketTCP<Payload>(new Payload(RequestResponseCode.VERSION_ERROR))).send(requestSocket);
 			throw e;
 		} catch (InternalError e) {
-			(new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
+			(new ProtocolP2PPacketTCP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
 			throw e;
 		} catch (SizeError e) {
-			(new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
+			(new ProtocolP2PPacketTCP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
 			throw e;
 		}
 	}
@@ -288,6 +307,18 @@ public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
 			case HASH_RESPONSE:
 				payload = (Payload) new HashResponse(packet);
 				break;
+			case REGISTER:
+				payload = (Payload) new Register(packet);
+				break;
+			case UNREGISTER:
+				payload = (Payload) new Unregister(packet);
+				break;
+			case DISCOVER_REQUEST:
+				payload = (Payload) new DiscoverRequest(packet);
+				break;
+			case DISCOVER_RESPONSE:
+				payload = (Payload) new DiscoverResponse(packet);
+				break;
 			default:
 				payload = new Payload(packet); // this can throw TransmissionError
 				break;
@@ -319,4 +350,15 @@ public class ProtocolP2PPacketTCP extends ProtocolP2PPacket {
 		return packet;
 	}
 
+	/** Get hostItem of the sender
+	 * @return	hostItem of the sender
+	 * @throws	InternalError
+	 */
+	public HostItem getHostItem() throws InternalError {
+		if (responseSocket == null) {
+			throw new InternalError();
+		}
+		return new HostItem(responseSocket.getInetAddress().getHostName(), responseSocket.getPort());
+	}
+
 }

src/protocolP2P/ProtocolP2PPacketUDP.java

@@ -1,10 +1,11 @@
 package protocolP2P;
-import exception.InternalError;
-import exception.ProtocolError;
-import exception.SizeError;
-import exception.TransmissionError;
-import exception.VersionError;
-import exception.SocketClosed;
+import localException.InternalError;
+import localException.ProtocolError;
+import localException.SizeError;
+import localException.TransmissionError;
+import localException.VersionError;
+import localException.SocketClosed;
+import remoteException.NotATracker;
 import remoteException.EmptyDirectory;
 import remoteException.InternalRemoteError;
 import remoteException.NotFound;
@@ -12,13 +13,12 @@ import remoteException.ProtocolRemoteError;
 import remoteException.VersionRemoteError;
 import remoteException.EmptyFile;
 import tools.BytesArrayTools;
+import tools.HostItem;
 import protocolP2P.Payload;
 import protocolP2P.RequestResponseCode;
 import protocolP2P.LoadRequest;
 import protocolP2P.FileList;
 import protocolP2P.FilePart;
-import java.util.ArrayList;
-import java.lang.Byte;
 import java.net.DatagramPacket;
 import java.net.DatagramSocket;
 import java.net.SocketAddress;
@@ -30,17 +30,18 @@ import java.io.IOException;
  * @author	JS Auge
  * @version	1.0
  */
-public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
-	
+public class ProtocolP2PPacketUDP < T extends Payload> extends ProtocolP2PPacket < T > {
+
 	private final static int CHECKSUM_POSITION = 2;
+	private HostItem remoteHost;
 	private SocketAddress responseSocketAddress; // socket address used when receptionning request and to sending response
 	private DatagramSocket responseSocket; // socket used to recept request and send response
 	private DatagramSocket requestSocket; // socket used to send request and to reception response
-	
+
 	/** Constructor with payload parameter (typically used when sending packet).
 	 * @param payload	the payload associated with the packet to send
 	 */
-	public ProtocolP2PPacketUDP(Payload payload) {
+	public ProtocolP2PPacketUDP(T payload) {
 		super(payload);
 	}
 
@@ -112,6 +113,7 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 		DatagramPacket reception = new DatagramPacket(packet, packet.length);
 		ss.receive(reception);
 		responseSocketAddress = reception.getSocketAddress();
+		remoteHost = new HostItem(reception.getAddress().getHostName(), reception.getPort());
 		// contruction
 		boolean protocolError = false;
 		try {
@@ -130,25 +132,27 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 				case LOAD_RESPONSE:
 				case LIST_RESPONSE:
 				case HASH_RESPONSE:
+				case DISCOVER_RESPONSE:
+				case NOT_A_TRACKER:
 					// we were expecting a request, but we are receiving a response
 					throw new ProtocolError();
 				default :
 					break;
 			}
 		} catch (TransmissionError e) {
-			(new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss, responseSocketAddress);
+			(new ProtocolP2PPacketUDP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss, responseSocketAddress);
 			throw e;
 		} catch (ProtocolError e) {
-			(new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.PROTOCOL_ERROR))).send(ss, responseSocketAddress);
+			(new ProtocolP2PPacketUDP<Payload>(new Payload(RequestResponseCode.PROTOCOL_ERROR))).send(ss, responseSocketAddress);
 			throw e;
 		} catch (VersionError e) {
-			(new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.VERSION_ERROR))).send(ss, responseSocketAddress);
+			(new ProtocolP2PPacketUDP<Payload>(new Payload(RequestResponseCode.VERSION_ERROR))).send(ss, responseSocketAddress);
 			throw e;
 		} catch (InternalError e) {
-			(new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss, responseSocketAddress);
+			(new ProtocolP2PPacketUDP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss, responseSocketAddress);
 			throw e;
 		} catch (SizeError e) {
-			(new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss, responseSocketAddress);
+			(new ProtocolP2PPacketUDP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(ss, responseSocketAddress);
 			throw e;
 		}
 		if (protocolError) {
@@ -161,10 +165,10 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 	 * @throws	InternalError
 	 * @throws	IOException
 	 */
-	public void sendResponse(ProtocolP2PPacket response) throws InternalError, IOException {
+	public <U extends ProtocolP2PPacket<?>>void sendResponse(U response) throws InternalError, IOException {
 		assert response instanceof ProtocolP2PPacketUDP: "Wrong Packet type";
 		if (response instanceof ProtocolP2PPacketUDP) {
-			ProtocolP2PPacketUDP r = (ProtocolP2PPacketUDP) response;
+			ProtocolP2PPacketUDP<?> r = (ProtocolP2PPacketUDP<?>) response;
 			assert responseSocket != null : "Cannot send response to a packet not received";
 			if (responseSocket == null) {
 				throw new InternalError();
@@ -183,6 +187,7 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 	 * @return	ProtocolP2PPacket received
 	 * @throws	EmptyFile
 	 * @throws	NotFound
+	 * @throws	NotATracker
 	 * @throws	EmptyDirectory
 	 * @throws	InternalRemoteError
 	 * @throws	VersionRemoteError
@@ -194,7 +199,7 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 	 * @throws	SizeError
 	 * @throws	IOException
 	 */
-	public ProtocolP2PPacket receiveResponse() throws EmptyFile, NotFound, EmptyDirectory, InternalRemoteError, VersionRemoteError, ProtocolRemoteError, TransmissionError, ProtocolError, VersionError, InternalError, SizeError, IOException {
+	public ProtocolP2PPacket<?> receiveResponse() throws EmptyFile, NotFound, NotATracker, EmptyDirectory, InternalRemoteError, VersionRemoteError, ProtocolRemoteError, TransmissionError, ProtocolError, VersionError, InternalError, SizeError, IOException {
 		assert requestSocket != null : "Cannot receive response because request packet not sent.";
 		if (requestSocket == null) {
 			throw new InternalError();
@@ -203,9 +208,10 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 		byte[] packet = new byte[8192];
 		DatagramPacket reception = new DatagramPacket(packet, packet.length);
 		requestSocket.receive(reception);
+		
 		// contruction
 		try {
-			ProtocolP2PPacketUDP p = new ProtocolP2PPacketUDP(packet);
+			ProtocolP2PPacketUDP<?> p = new ProtocolP2PPacketUDP<>(packet);
 			Payload payload = p.getPayload();
 			switch (payload.getRequestResponseCode()) {
 				case PROTOCOL_ERROR :
@@ -220,23 +226,25 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 					throw new NotFound();
 				case EMPTY_FILE:
 					throw new EmptyFile();
+				case NOT_A_TRACKER:
+					throw new NotATracker();
 				default :
 					return (ProtocolP2PPacket)p;
 			}
 		} catch (TransmissionError e) {
-			(new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
+			(new ProtocolP2PPacketUDP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
 			throw e;
 		} catch (ProtocolError e) {
-			(new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.PROTOCOL_ERROR))).send(requestSocket);
+			(new ProtocolP2PPacketUDP<Payload>(new Payload(RequestResponseCode.PROTOCOL_ERROR))).send(requestSocket);
 			throw e;
 		} catch (VersionError e) {
-			(new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.VERSION_ERROR))).send(requestSocket);
+			(new ProtocolP2PPacketUDP<Payload>(new Payload(RequestResponseCode.VERSION_ERROR))).send(requestSocket);
 			throw e;
 		} catch (InternalError e) {
-			(new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
+			(new ProtocolP2PPacketUDP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
 			throw e;
 		} catch (SizeError e) {
-			(new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
+			(new ProtocolP2PPacketUDP<Payload>(new Payload(RequestResponseCode.INTERNAL_ERROR))).send(requestSocket);
 			throw e;
 		}
 	}
@@ -284,6 +292,18 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 			case HASH_RESPONSE:
 				payload = (Payload) new HashResponse(packet);
 				break;
+			case REGISTER:
+				payload = (Payload) new Register(packet);
+				break;
+			case UNREGISTER:
+				payload = (Payload) new Unregister(packet);
+				break;
+			case DISCOVER_REQUEST:
+				payload = (Payload) new DiscoverRequest(packet);
+				break;
+			case DISCOVER_RESPONSE:
+				payload = (Payload) new DiscoverResponse(packet);
+				break;
 			default:
 				payload = new Payload(packet); // this can throw TransmissionError
 				break;
@@ -353,7 +373,6 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 	* @param packet	full packet
 	* @throws TransmissionError
 	*/
-
 	private void checkCheckSum(byte [] packet) throws TransmissionError {
 		try {
 			int checksum = BytesArrayTools.readInt16Bits(packet, CHECKSUM_POSITION);
@@ -365,4 +384,15 @@ public class ProtocolP2PPacketUDP extends ProtocolP2PPacket {
 			throw new TransmissionError();
 		}
 	}
+
+	/** Get hostItem of the sender
+	 * @return	hostItem of the sender
+	 * @throws	InternalError
+	 */
+	public HostItem getHostItem() throws InternalError {
+		if (remoteHost == null) {
+			throw new InternalError();
+		}
+		return remoteHost;
+	}
 }

src/protocolP2P/Register.java

@@ -0,0 +1,77 @@
+package protocolP2P;
+import protocolP2P.Payload;
+import tools.HostItem;
+import tools.BytesArrayTools;
+import localException.SizeError;
+import localException.InternalError;
+import localException.TransmissionError;
+import localException.ProtocolError;
+
+/** Representation of payload for unregister.
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public class Register extends Payload {
+	private HostItem hostItem;
+	private static final int HOSTNAME_START_POSITION = PAYLOAD_START_POSITION + 2;
+
+	/** Constructor with hostItem (typically used by client)
+	 * @param hostItem	Host you want to register.
+	 * @throws	InternalError
+	 */
+	public Register(HostItem hostItem) throws InternalError {
+		super(RequestResponseCode.REGISTER);
+		this.hostItem = hostItem;
+	}
+	
+	/** Constructor (typically used by server) with a byte[] parameter containing the Packet received.
+	 * @param packet	the full Packet received
+	 * @throws	SizeError
+	 * @throws	InternalError
+	 * @throws	ProtocolError
+	 * @throws	TransmissionError
+	 */
+	protected Register(byte[] packet) throws SizeError, ProtocolError, InternalError, TransmissionError {
+		super(packet);
+		int size = getPayloadSize(packet);
+		int port = BytesArrayTools.readInt16Bits(packet, PAYLOAD_START_POSITION);
+		String hostname = BytesArrayTools.readString(packet, HOSTNAME_START_POSITION, size - HOSTNAME_START_POSITION + PAYLOAD_START_POSITION);
+		hostItem = new HostItem(hostname, port);
+	}
+
+	/** Returns a byte[] containing Packet with padding.
+	 * This Packet is still incomplete and should not be send directly.
+	 * ProtocolP2PPacket will use this method to generate the complete Packet.
+	 * @return Packet with padding
+	 * @throws	InternalError
+	 */
+	protected byte[] toPacket() throws InternalError {
+		String hostname = hostItem.getHostname();
+		// compute total size
+		int size = HOSTNAME_START_POSITION + hostname.length();
+		byte[] packet = new byte[size + 1]; // java initialize all to zero
+		// set request/response code
+		packet[RequestResponseCode.RRCODE_POSITION] = requestResponseCode.codeValue;
+		// set Payload size
+		setPayloadSize(size - PAYLOAD_START_POSITION, packet);
+		// write port to Packet
+		try {
+			BytesArrayTools.write16Bits(packet, PAYLOAD_START_POSITION, hostItem.getPort());
+		} catch (SizeError e) {
+			throw new InternalError();
+		}
+		// write hostname to Packet
+		BytesArrayTools.write(packet, hostname, HOSTNAME_START_POSITION);
+		return packet;
+	}
+
+	/** HostItem getter.
+	 * @return	hostItem
+	 */
+	public HostItem getHostItem() {
+		return hostItem;
+	}
+
+}

src/protocolP2P/RequestResponseCode.java

@@ -1,6 +1,6 @@
 package protocolP2P;
 import protocolP2P.CodeType;
-import exception.ProtocolError;
+import localException.ProtocolError;
 import java.util.HashMap;
 import java.util.Map;
 import java.lang.Byte;
@@ -15,16 +15,21 @@ public enum RequestResponseCode {
 	LIST_REQUEST(CodeType.REQUEST, (byte)0x00),
 	LOAD_REQUEST(CodeType.REQUEST, (byte)0x01),
 	HASH_REQUEST(CodeType.REQUEST, (byte)0x02),
+	DISCOVER_REQUEST(CodeType.REQUEST_TRACKER, (byte)0x03),
+	REGISTER(CodeType.REQUEST_TRACKER, (byte)0x04),
+	UNREGISTER(CodeType.REQUEST_TRACKER, (byte)0x05),
 	LIST_RESPONSE(CodeType.RESPONSE, (byte)0x80),
 	LOAD_RESPONSE(CodeType.RESPONSE, (byte)0x81),
 	HASH_RESPONSE(CodeType.RESPONSE, (byte)0x82),
+	DISCOVER_RESPONSE(CodeType.RESPONSE, (byte)0x83),
 	VERSION_ERROR(CodeType.ERROR, (byte)0xC0),
 	PROTOCOL_ERROR(CodeType.ERROR, (byte)0xC1),
 	INTERNAL_ERROR(CodeType.ERROR, (byte)0xC2),
 	EMPTY_DIRECTORY(CodeType.ERROR, (byte)0xC3),
 	NOT_FOUND(CodeType.ERROR, (byte)0xC4),
-	EMPTY_FILE(CodeType.ERROR, (byte)0xC5);
-	
+	EMPTY_FILE(CodeType.ERROR, (byte)0xC5),
+	NOT_A_TRACKER(CodeType.ERROR, (byte)0xC6);
+
 	public final CodeType codeType;
 	public final byte codeValue;
 	protected final static int RRCODE_POSITION = 1;
@@ -62,7 +67,5 @@ public enum RequestResponseCode {
 		return r;
 	}
 
-	
-}
-
 
+}

src/protocolP2P/Unregister.java

@@ -0,0 +1,77 @@
+package protocolP2P;
+import protocolP2P.Payload;
+import tools.HostItem;
+import tools.BytesArrayTools;
+import localException.SizeError;
+import localException.InternalError;
+import localException.TransmissionError;
+import localException.ProtocolError;
+
+/** Representation of payload for unregister.
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public class Unregister extends Payload {
+	private HostItem hostItem;
+	private static final int HOSTNAME_START_POSITION = PAYLOAD_START_POSITION + 2;
+
+	/** Constructor with hostItem (typically used by client)
+	 * @param hostItem	Host you want to register.
+	 * @throws	InternalError
+	 */
+	public Unregister(HostItem hostItem) throws InternalError {
+		super(RequestResponseCode.UNREGISTER);
+		this.hostItem = hostItem;
+	}
+	
+	/** Constructor (typically used by server) with a byte[] parameter containing the Packet received.
+	 * @param packet	the full Packet received
+	 * @throws	SizeError
+	 * @throws	InternalError
+	 * @throws	ProtocolError
+	 * @throws	TransmissionError
+	 */
+	protected Unregister(byte[] packet) throws SizeError, ProtocolError, InternalError, TransmissionError {
+		super(packet);
+		int size = getPayloadSize(packet);
+		int port = BytesArrayTools.readInt16Bits(packet, PAYLOAD_START_POSITION);
+		String hostname = BytesArrayTools.readString(packet, HOSTNAME_START_POSITION, size - HOSTNAME_START_POSITION + PAYLOAD_START_POSITION);
+		hostItem = new HostItem(hostname, port);
+	}
+
+	/** Returns a byte[] containing Packet with padding.
+	 * This Packet is still incomplete and should not be send directly.
+	 * ProtocolP2PPacket will use this method to generate the complete Packet.
+	 * @return Packet with padding
+	 * @throws	InternalError
+	 */
+	protected byte[] toPacket() throws InternalError {
+		String hostname = hostItem.getHostname();
+		// compute total size
+		int size = HOSTNAME_START_POSITION + hostname.length();
+		byte[] packet = new byte[size + 1]; // java initialize all to zero
+		// set request/response code
+		packet[RequestResponseCode.RRCODE_POSITION] = requestResponseCode.codeValue;
+		// set Payload size
+		setPayloadSize(size - PAYLOAD_START_POSITION, packet);
+		// write port to Packet
+		try {
+			BytesArrayTools.write16Bits(packet, PAYLOAD_START_POSITION, hostItem.getPort());
+		} catch (SizeError e) {
+			throw new InternalError();
+		}
+		// write hostname to Packet
+		BytesArrayTools.write(packet, hostname, HOSTNAME_START_POSITION);
+		return packet;
+	}
+
+	/** HostItem getter.
+	 * @return	hostItem
+	 */
+	public HostItem getHostItem() {
+		return hostItem;
+	}
+
+}

src/remoteException/EmptyDirectory.java

@@ -1,4 +1,7 @@
 package remoteException;
-public class EmptyDirectory extends Exception {
+
+import exception.RemoteException;
+
+public class EmptyDirectory extends RemoteException {
 	private static final long serialVersionUID = 12L;
 }

src/remoteException/EmptyFile.java

@@ -1,4 +1,7 @@
 package remoteException;
-public class EmptyFile extends Exception {
+
+import exception.RemoteException;
+
+public class EmptyFile extends RemoteException {
 	private static final long serialVersionUID = 12L;
 }

src/remoteException/InternalRemoteError.java

@@ -1,4 +1,7 @@
 package remoteException;
-public class InternalRemoteError extends Exception {
+
+import exception.RemoteException;
+
+public class InternalRemoteError extends RemoteException {
 	private static final long serialVersionUID = 12L;
 }

src/remoteException/NotATracker.java

@@ -0,0 +1,7 @@
+package remoteException;
+
+import exception.RemoteException;
+
+public class NotATracker extends RemoteException {
+	private static final long serialVersionUID = 12L;
+}

src/remoteException/NotFound.java

@@ -1,4 +1,7 @@
 package remoteException;
-public class NotFound extends Exception {
+
+import exception.RemoteException;
+
+public class NotFound extends RemoteException {
 	private static final long serialVersionUID = 12L;
 }

src/remoteException/ProtocolRemoteError.java

@@ -1,4 +1,7 @@
 package remoteException;
-public class ProtocolRemoteError extends Exception {
+
+import exception.RemoteException;
+
+public class ProtocolRemoteError extends RemoteException {
 	private static final long serialVersionUID = 12L;
 }

src/remoteException/VersionRemoteError.java

@@ -1,4 +1,7 @@
 package remoteException;
-public class VersionRemoteError extends Exception {
+
+import exception.RemoteException;
+
+public class VersionRemoteError extends RemoteException {
 	private static final long serialVersionUID = 12L;
 }

src/serverP2P/FileWatcher.java

@@ -0,0 +1,156 @@
+package serverP2P;
+import tools.Logger;
+import tools.LogLevel;
+import tools.HostItem;
+import java.io.File;
+import java.util.Vector;
+import java.util.Arrays;
+import java.util.Map;
+import java.util.HashMap;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import protocolP2P.HashAlgorithm;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.io.IOException;
+
+/** Class allowing to keep the tracker informed about file list
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public abstract class FileWatcher implements Runnable {
+	protected String[] fileList = new String[0];
+	protected Logger logger;
+	protected volatile boolean stop;
+	protected long time;
+	protected boolean force;
+	protected HostItem server;
+	protected HostItem tracker;
+	protected String baseDirectory;
+	protected Map<String, byte[]> sha512 = new HashMap<>();
+
+
+	/** Constructor
+	 * @param logger	Logger
+	 * @param millis	Time interval before recheck
+	 * @param server	HostItem for the server
+	 * @param tracker	HostItem for the tracker
+	 * @param baseDirectory	Directory to search files
+	 */
+	public FileWatcher(Logger logger, long millis, HostItem server, HostItem tracker, String baseDirectory) {
+		assert logger != null : "Logger is null";
+		assert server != null : "Server is null";
+		assert tracker != null : "Tracker is null";
+		assert baseDirectory != null : "baseDirectory is null";
+		this.logger = logger;
+		time = millis;
+		this.server = server;
+		this.tracker = tracker;
+		this.baseDirectory = baseDirectory;
+	}
+
+	/** FileList getter
+	 * @return fileList
+	 */
+	public String[] getFileList() {
+		return fileList;
+	}
+
+	/** Sha512 map getter
+	 * @return sha512 hashmap
+	 */
+	public Map<String, byte[]> getSha512Map() {
+		return sha512;
+	}
+
+	/** Allow a manual check
+	 */
+	public void trigger() {
+		if (updateFileList() || force) {
+			force = false;
+			writeLog("File list watcher detected changes. Informing tracker.", LogLevel.Info);
+			registerTracker();
+		}
+	}
+
+	/** Runnable implementation */
+	public void run() {
+		writeLog("File list watcher started : delay " + time + " milliseconds.", LogLevel.Info);
+		while(!stop) {
+			trigger();
+			try {
+				Thread.sleep(time);
+			} catch(InterruptedException e) {
+				writeLog("File list watcher interrupted", LogLevel.Error);
+				setStop();
+			}
+		}
+	}
+
+	/** Register server on tracker
+	 */
+	protected abstract void registerTracker();
+
+	/** Update fileList and returns true if different than old list.
+	 * @return	true if changed
+	 */
+	protected boolean updateFileList() {
+		File folder = new File(baseDirectory);
+		Vector<String> v = new Vector<String>();
+		File[] files = folder.listFiles();
+		/* Add non-recursively files's names to fileList */
+		for (File f : files) {
+			if (f.isFile()) {
+				v.add(f.getName());
+			}
+		}
+		String[] newFileList = new String[v.size()];
+		v.toArray(newFileList);
+		Arrays.sort(newFileList);
+		if (!Arrays.equals(newFileList, fileList)) {
+			fileList = newFileList;
+			initSha512();
+			return true;
+		} else {
+			return false;
+		}
+	}
+
+	
+	/** Ask the thread to stop
+	 */
+	public void setStop() {
+		stop = true;
+	}
+
+	/** Init sha512 map.
+	 */
+	protected void initSha512() {
+		for(String f: fileList) {
+			try {
+				MessageDigest md = MessageDigest.getInstance(HashAlgorithm.SHA512.getName());
+				sha512.put(f, md.digest(Files.readAllBytes(Paths.get(baseDirectory + f))));
+				md.reset();
+			} catch (NoSuchAlgorithmException e) {
+				writeLog("sha512 not supported", LogLevel.Error);
+			} catch (IOException e) {
+				writeLog("cannot read " + f, LogLevel.Warning);
+			}
+		}
+	}
+
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
+	 */
+	protected abstract void writeLog(String text, LogLevel logLevel);
+
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
+	 */
+	protected abstract void writeLog(Exception e, LogLevel logLevel);
+
+}

src/serverP2P/FileWatcherTCP.java

@@ -0,0 +1,65 @@
+package serverP2P;
+import tools.Logger;
+import tools.LogLevel;
+import protocolP2P.ProtocolP2PPacket;
+import protocolP2P.ProtocolP2PPacketTCP;
+import protocolP2P.Register;
+import protocolP2P.Payload;
+import tools.HostItem;
+
+/** Class allowing to keep the tracker informed about file list (TCP impl.)
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public class FileWatcherTCP extends FileWatcher {
+
+	/** Constructor
+	 * @param logger	Logger
+	 * @param millis	Time interval before recheck
+	 * @param server	HostItem for the server
+	 * @param tracker	HostItem for the tracker
+	 * @param baseDirectory	Directory to search files
+	 */
+	public FileWatcherTCP(Logger logger, long millis, HostItem server, HostItem tracker, String baseDirectory) {
+		super(logger, millis, server, tracker, baseDirectory);
+		assert logger != null : "Logger is null";
+		assert server != null : "Server is null";
+		assert tracker != null : "Tracker is null";
+		assert baseDirectory != null : "baseDirectory is null";
+	}
+
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
+	 */
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeTCP(text, logLevel);
+	}
+
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
+	 */
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeTCP(e, logLevel);
+	}
+
+	/** Register server on tracker
+	 */
+	protected void registerTracker() {
+		try {
+			writeLog("Trying to into tracker", LogLevel.Info);
+			ProtocolP2PPacket<Register> p = (ProtocolP2PPacket<Register>)new ProtocolP2PPacketTCP<Register>(new Register(server));
+			p.sendRequest((Object)tracker.tryGetTCPSocket());
+			writeLog("Register request sent.", LogLevel.Debug);
+			tracker.closeTCPSocket();
+		} catch (Exception e) {
+			// error, trying again at next iteration
+			force = true;
+			writeLog("Cannot contact tracker, trying again at next iteration (" + time + " milliseconds).", LogLevel.Error);
+		}
+	}
+
+}

src/serverP2P/FileWatcherUDP.java

@@ -0,0 +1,64 @@
+package serverP2P;
+import tools.Logger;
+import tools.LogLevel;
+import protocolP2P.ProtocolP2PPacket;
+import protocolP2P.ProtocolP2PPacketUDP;
+import protocolP2P.Register;
+import protocolP2P.Payload;
+import tools.HostItem;
+
+/** Class allowing to keep the tracker informed about file list (UDP impl.)
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public class FileWatcherUDP extends FileWatcher {
+
+	/** Constructor
+	 * @param logger	Logger
+	 * @param millis	Time interval before recheck
+	 * @param server	HostItem for the server
+	 * @param tracker	HostItem for the tracker
+	 * @param baseDirectory	Directory to search files
+	 */
+	public FileWatcherUDP(Logger logger, long millis, HostItem server, HostItem tracker, String baseDirectory) {
+		super(logger, millis, server, tracker, baseDirectory);
+		assert logger != null : "Logger is null";
+		assert server != null : "Server is null";
+		assert tracker != null : "Tracker is null";
+		assert baseDirectory != null : "baseDirectory is null";
+	}
+
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
+	 */
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeUDP(text, logLevel);
+	}
+
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
+	 */
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeUDP(e, logLevel);
+	}
+
+	/** Register server on tracker
+	 */
+	protected void registerTracker() {
+		try {
+			writeLog("Trying to register into tracker", LogLevel.Info);
+			ProtocolP2PPacket<Register> p = (ProtocolP2PPacket<Register>)new ProtocolP2PPacketUDP<Register>(new Register(server));
+			p.sendRequest((Object)tracker.getUDPSocket());
+			writeLog("Register request sent (but cannot ensure reception).", LogLevel.Debug);
+			tracker.closeUDPSocket();
+		} catch (Exception e) {
+			force = true;
+			writeLog("Cannot contact tracker, trying again at next iteration (" + time + " milliseconds).", LogLevel.Error);
+		}
+	}
+
+}

src/serverP2P/ServerManagement.java

@@ -0,0 +1,234 @@
+package serverP2P;
+import serverP2P.FileWatcher;
+import tools.Logger;
+import tools.LogLevel;
+import tools.HostItem;
+import tools.ServeErrors;
+import protocolP2P.ProtocolP2PPacket;
+import protocolP2P.Payload;
+import protocolP2P.RequestResponseCode;
+import protocolP2P.FileList;
+import protocolP2P.FilePart;
+import protocolP2P.LoadRequest;
+import protocolP2P.HashRequest;
+import protocolP2P.HashResponse;
+import protocolP2P.HashAlgorithm;
+import protocolP2P.Unregister;
+import java.nio.file.Paths;
+import java.nio.file.Files;
+import java.util.Arrays;
+import java.util.Map;
+import java.util.HashMap;
+import java.io.IOException;
+import exception.LocalException;
+
+/** Implementation of P2P-JAVA-PROJECT VERSION 1.0 protocol.
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public abstract class ServerManagement extends ServeErrors implements Runnable {
+
+	protected volatile boolean stop;
+	protected FileWatcher fileListWatcher;
+	protected Logger logger;
+	protected String baseDirectory;
+	protected HostItem server;
+	protected HostItem tracker;
+
+	/** Constructor */
+	public ServerManagement(String baseDirectory, HostItem server, HostItem tracker, Logger logger) {
+		super();
+		assert baseDirectory != null : "baseDirectory is null";
+		assert server != null : "server is null";
+		assert tracker != null : "tracker is null";
+		assert logger != null : "logger is null";
+		stop = false;
+		this.baseDirectory = baseDirectory;
+		this.server = server;
+		this.tracker = tracker;
+		this.logger = logger;
+	}
+
+	/** Stop the thread */
+	public void setStop() {
+		stop = true;
+	}
+
+	/** Trigger a manual check of the file list
+	 */
+	public void updateFileList() {
+		if (fileListWatcher != null) {
+			fileListWatcher.trigger();
+		}
+	}
+
+	/** Send response to list request
+	 * @param pd	Request received
+	 */
+	protected < T extends ProtocolP2PPacket<?> > void sendListResponse(T pd) {
+		try {
+			String[] fileList = fileListWatcher.getFileList();
+			if (fileList.length == 0) {
+				writeLog("Sending EMPTY_DIRECTORY to host " + pd.getHostItem(), LogLevel.Action);
+				sendEmptyDirectory(pd);
+			} else {
+				writeLog("Sending LIST_RESPONSE to host " + pd.getHostItem(), LogLevel.Action);
+				pd.sendResponse(createProtocolP2PPacket((Payload)(new FileList(fileList))));
+			}
+		} catch (Exception e2) {
+			writeLog(e2, LogLevel.Error);
+		}
+	}
+
+
+
+	/** Send hash response to hash request
+	 * @param pd	Request received
+	 */
+	protected < T extends ProtocolP2PPacket<?> > void sendHashResponse(T pd) {
+		Payload p = pd.getPayload();
+		assert p instanceof HashRequest : "payload must be an instance of HashRequest";
+		if (!(p instanceof HashRequest)) {
+			sendInternalError(pd);
+		} else {
+			String filename = ((HashRequest)p).getFilename();
+			if (Arrays.binarySearch(fileListWatcher.getFileList(), filename) >= 0) {
+				Map<HashAlgorithm, byte[]> hashes = new HashMap<>();
+				for (HashAlgorithm h : ((HashRequest)p).getAlgoList()) {
+					switch (h) {
+						case SHA512:
+							hashes.put(h, fileListWatcher.getSha512Map().get(filename));
+							break;
+						case MD5:
+						default:
+							hashes.put(h, new byte[0]);
+							break;
+					}
+				}
+				try {
+					pd.sendResponse(createProtocolP2PPacket((Payload)(new HashResponse(filename, hashes))));
+				} catch (Exception e) {
+					writeLog(e, LogLevel.Error);
+				}
+			} else {
+				// file not found
+				try {
+					sendNotFound(pd);
+				} catch (Exception e) {
+					writeLog(e, LogLevel.Error);
+				}
+			}
+		}
+	}
+
+	/** Send response to load request
+	 * @param pd	Request received
+	 */
+	protected < T extends ProtocolP2PPacket<?> > void sendLoadResponse(T pd) {
+		Payload p = pd.getPayload();
+		assert p instanceof LoadRequest : "payload must be an instance of LoadRequest";
+		if (!(p instanceof LoadRequest)) {
+			sendInternalError(pd);
+		} else {
+			String filename = ((LoadRequest)p).getFilename();
+			long offset = ((LoadRequest)p).getOffset();
+			long maxSizePartialContent = ((LoadRequest)p).getMaxSizePartialContent();
+			try {
+				byte[] fullLoad = Files.readAllBytes(Paths.get(baseDirectory + filename));
+				long sizeToSend = 0;
+				if (fullLoad.length - offset < maxSizePartialContent) {
+					writeLog("Sending last partialContent", LogLevel.Debug);
+					sizeToSend = fullLoad.length - offset;
+				} else {
+					sizeToSend = maxSizePartialContent;
+				}
+				writeLog("maxSizePartialContent: " + maxSizePartialContent, LogLevel.Debug);
+				writeLog("Sending " + filename + " from " + offset + " to " + (offset + sizeToSend), LogLevel.Debug);
+				byte[] load = Arrays.copyOfRange(fullLoad, (int)offset, (int)(offset + sizeToSend));
+				String[] fileList = fileListWatcher.getFileList();
+				if (Arrays.binarySearch(fileList, filename) >= 0) {
+					try {
+						if (load.length == 0) {
+							sendEmptyFile(pd);
+						} else {
+							pd.sendResponse(createProtocolP2PPacket((Payload)(new FilePart(filename, fullLoad.length, offset, load))));
+						}
+					} catch (Exception e2) {
+						writeLog(e2, LogLevel.Error);
+					}
+				} else {
+					writeLog("File requested not found: `" + filename + "` " + Arrays.binarySearch(fileList, filename), LogLevel.Debug);
+					writeLog("File list:", LogLevel.Debug);
+					for (String f: fileList) {
+						writeLog("- " + f, LogLevel.Debug);
+					}
+
+					throw new IOException(); // to send a NOT_FOUND in the catch block
+				}
+			} catch (IOException e) {
+				try {
+					sendNotFound(pd);
+				} catch (Exception e2) {
+					writeLog(e2, LogLevel.Debug);
+				}
+			}
+		}
+	}
+
+
+	/** Getter for tracker socket
+	 */
+	protected abstract Object getTrackerSocket(); 
+
+	/** Send unregister request to tracker
+	 */
+	 protected void sendUnregisterRequest() {
+		// unregistering from tracker
+		try {
+			writeLog("Unregistering from tracker", LogLevel.Info);
+			createProtocolP2PPacket(new Unregister(server)).sendRequest(getTrackerSocket());
+		} catch (Exception e) {
+			writeLog("Cannot unregister from tracker", LogLevel.Error);
+			writeLog(e, LogLevel.Error);
+		}
+	}
+
+	/** Handle request.
+	 * @throws	LocalException
+	 */
+	 protected < T extends ProtocolP2PPacket<?> > void handleRequest(T pd) throws LocalException {
+		 Payload p = pd.getPayload();
+		 switch (p.getRequestResponseCode()) {
+			case LOAD_REQUEST:
+				writeLog("Received LOAD_REQUEST from host " + pd.getHostItem(), LogLevel.Action);
+				sendLoadResponse(pd);
+				break;
+			case LIST_REQUEST:
+				writeLog("Received LIST_REQUEST from host " + pd.getHostItem(), LogLevel.Action);
+				sendListResponse(pd);
+				break;
+			case HASH_REQUEST:
+				writeLog("Received HASH_REQUEST from host " + pd.getHostItem(), LogLevel.Action);
+				sendHashResponse(pd);
+				break;
+			case DISCOVER_REQUEST:
+				writeLog("Received DISCOVER_REQUEST from host " + pd.getHostItem(), LogLevel.Action);
+				sendNotATracker(pd);
+				break;
+			case UNREGISTER:
+				writeLog("Received UNREGISTER from host " + pd.getHostItem(), LogLevel.Action);
+				sendNotATracker(pd);
+				break;
+			case REGISTER:
+				writeLog("Received REGISTER from host " + pd.getHostItem(), LogLevel.Action);
+				sendNotATracker(pd);
+				break;
+			default:
+				writeLog("Received grabbage from host " + pd.getHostItem(), LogLevel.Action);
+				sendInternalError(pd);
+		}
+	}
+
+}

src/serverP2P/ServerManagementTCP.java

@@ -17,26 +17,26 @@ import protocolP2P.Payload;
 import protocolP2P.LoadRequest;
 import protocolP2P.FileList;
 import protocolP2P.FilePart;
-import exception.InternalError;
-import exception.ProtocolError;
-import exception.SizeError;
-import exception.TransmissionError;
-import exception.VersionError;
-import exception.SocketClosed;
-import remoteException.EmptyDirectory;
-import remoteException.InternalRemoteError;
-import remoteException.NotFound;
-import remoteException.ProtocolRemoteError;
-import remoteException.VersionRemoteError;
-import remoteException.EmptyFile;
+import localException.InternalError;
+import localException.ProtocolError;
+import localException.SizeError;
+import localException.TransmissionError;
+import localException.VersionError;
+import localException.SocketClosed;
+import exception.LocalException;
 import java.util.Arrays;
 import tools.Logger;
 import tools.LogLevel;
+import tools.HostItem;
 import java.util.HashMap;
 import java.util.Map;
 import protocolP2P.HashAlgorithm;
 import protocolP2P.HashRequest;
 import protocolP2P.HashResponse;
+import protocolP2P.Register;
+import protocolP2P.Unregister;
+import serverP2P.ServerManagement;
+import serverP2P.FileWatcherTCP;
 
 
 /** Implementation of P2P-JAVA-PROJECT VERSION 1.0 protocol for TCP.
@@ -45,268 +45,121 @@ import protocolP2P.HashResponse;
  * @author	JS Auge
  * @version	1.0
  */
-public class ServerManagementTCP implements Runnable {
+public class ServerManagementTCP extends ServerManagement {
 
-	private String[] fileList;
-	private Map<String, byte[]> sha512 = new HashMap<>();
-	private String baseDirectory;
-	private int TCPPort;
 	private ServerSocket socket;
-	private Logger logger;
 
 	/** Constructor for TCP implementation, with baseDirectory and TCPPort parameters.
 	 * @param baseDirectory	the root directory where files are stored
+	 * @param hostName	the server will bind on this address
 	 * @param TCPPort	the server will listen on this port
+	 * @param logger	Logger item
+	 * @param tracker	Tracker
 	 */
-	public ServerManagementTCP(String baseDirectory, int TCPPort, Logger logger) {
-		this.logger = logger;
-		this.baseDirectory = baseDirectory;
-		this.TCPPort = TCPPort;
-		initFileList();
-		initSha512();
+	public ServerManagementTCP(String baseDirectory, HostItem server, HostItem tracker, Logger logger) {
+		super(baseDirectory, server, tracker, logger);
+		assert baseDirectory != null : "baseDirectory is null";
+		assert server != null : "server is null";
+		assert tracker != null : "tracker is null";
+		assert logger != null : "logger is null";
 		try {
-			socket = new ServerSocket(TCPPort);
+			socket = new ServerSocket(server.getPort(), 10, server.getInetAddress());
 		} catch (SocketException e) {
-			logger.writeTCP("Error: cannot listen on port " + TCPPort, LogLevel.Error);
+			writeLog("Error: cannot listen on " + server, LogLevel.Error);
 			System.exit(-1);
 		} catch (IOException e) {
-			logger.writeTCP("Error: cannot openning socket", LogLevel.Error);
+			writeLog("Error: cannot openning socket", LogLevel.Error);
 			System.exit(-2);
 		}
 	}
 
+	
 	/** Implementation of runnable. This methods allows to run the server.
 	 */
 	public void run() {
-		logger.writeTCP("Server sucessfully started", LogLevel.Info);
-		do {
+		writeLog("Server sucessfully started", LogLevel.Info);
+		fileListWatcher = (FileWatcher)new FileWatcherTCP(logger, 10000, server, tracker, baseDirectory); // checking every 10 seconds
+		(new Thread(fileListWatcher)).start();
+		while(!stop) {
 			try {
 				Socket s = socket.accept();
 				ClientHandler c = new ClientHandler(s);
 				(new Thread(c)).start();
 			} catch (IOException e) {
-				logger.writeTCP("Error while accepting new connection", LogLevel.Warning);
+				writeLog("Error while accepting new connection", LogLevel.Warning);
 			}
-		} while(true);
+		}
+		fileListWatcher.setStop();
+		sendUnregisterRequest();
 	}
 
 	/** Private runnable class allowing to serve one client.
 	 */
 	private class ClientHandler implements Runnable {
-		private Socket s;
-		private String addr;
+		private HostItem addr;
 		/** Constructor with a socket.
 		 * @param	s	Socket of this client
 		 */
 		public ClientHandler(Socket s) {
-			this.s = s;
-			this.addr = "[" +s.getInetAddress().getHostAddress() + "]:" + s.getPort() + " ";
+			addr = new HostItem(s);
 		}
 
 		/** Implementation of runnable. This method allow to serve one client.
 		 */
 		public void run() {
-			
+
 			boolean end = false;
-			logger.writeTCP(addr + "New connection", LogLevel.Action);
+			writeLog("[" + addr + "] New connection", LogLevel.Action);
 			do {
-				end = handleRequest();
+				end = handleClientRequest();
 			} while(!end);
-			logger.writeTCP(addr + "End of connection", LogLevel.Action);
+			writeLog("[" + addr + "] End of connection", LogLevel.Action);
 		}
 
 		/** Respond to next request incomming on socket s.
 		 * @param s	Socket used to read request and send response
 		 * @return	true if cannot expect another request (ie, socket is closed)
 		 */
-		private boolean handleRequest() {
+		private boolean handleClientRequest() {
 			try {
-				ProtocolP2PPacketTCP pd = new ProtocolP2PPacketTCP((Object)s);
-				Payload p = pd.getPayload();
-				switch (p.getRequestResponseCode()) {
-					case LOAD_REQUEST:
-						logger.writeTCP(addr + "LOAD_REQUEST", LogLevel.Action);
-						sendLoadResponse(pd);
-						break;
-					case LIST_REQUEST:
-						logger.writeTCP(addr + "LIST_REQUEST", LogLevel.Action);
-						sendListResponse(pd);
-						break;
-					case HASH_REQUEST:
-						logger.writeTCP(addr + "HASH_REQUEST", LogLevel.Action);
-						sendHashResponse(pd);
-						break;
-					default:
-						logger.writeTCP(addr + "Received grabbage", LogLevel.Action);
-						sendInternalError(pd);
-				}
+				ProtocolP2PPacketTCP<?> pd = new ProtocolP2PPacketTCP<>((Object)addr.getTCPSocket());
+				handleRequest(pd);
 			} catch (IOException e) {
 				return true;
 			} catch (SocketClosed e) {
 				return true;
 			}
-			catch (TransmissionError e) {}
-			catch (ProtocolError e) {}
-			catch (VersionError e) {}
-			catch (InternalError e) {}
-			catch (SizeError e) {}
+			catch (LocalException e) {}
 			return false;
 		}
 	}
 
-	/** Initialize local list of all files allowed to be shared.
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
 	 */
-	private void initFileList() {
-		File folder = new File(baseDirectory);
-		Vector<String> v = new Vector<String>();
-		File[] files = folder.listFiles();
-		/* Add non-recursively files's names to fileList */
-		for (File f : files) {
-			if (f.isFile()) {
-				v.add(f.getName());
-			}
-		}
-		fileList = new String[v.size()];
-		v.toArray(fileList);
-		Arrays.sort(fileList);
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeTCP(text, logLevel);
 	}
 
-	/** Init sha512 map.
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
 	 */
-	 private void initSha512() {
-		for(String f: fileList) {
-			try {
-				MessageDigest md = MessageDigest.getInstance(HashAlgorithm.SHA512.getName()); 
-				sha512.put(f, md.digest(Files.readAllBytes(Paths.get(baseDirectory + f))));
-				md.reset();
-			} catch (NoSuchAlgorithmException e) {
-				logger.writeTCP("sha512 not supported", LogLevel.Error);
-			} catch (IOException e) {
-				logger.writeTCP("cannot read " + f, LogLevel.Warning);
-			}
-		}
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeTCP(e, logLevel);
 	}
 
-	/** Send an internal error message.
-	 * @param pd	ProtocolP2PPacketTCP to respond
+	/** Create packets
+	 * @param payload	Payload
 	 */
-	private void sendInternalError(ProtocolP2PPacketTCP pd) {
-		logger.writeTCP("Internal Error", LogLevel.Warning);
-		try {
-			pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.INTERNAL_ERROR)));
-		} catch (Exception e) {
-			logger.writeTCP(e, LogLevel.Error);
-		}
+	protected < T extends Payload > ProtocolP2PPacket<T> createProtocolP2PPacket(T payload) {
+		return (ProtocolP2PPacket<T>)new ProtocolP2PPacketTCP<T>(payload);
 	}
 
-	/** Send response to list request
-	 * @param pd	Request received
+	/** Getter for tracker socket
 	 */
-	private void sendListResponse(ProtocolP2PPacketTCP pd) {
-		try {
-			if (fileList.length == 0) {
-				logger.writeTCP("Sending EMPTY_DIRECTORY", LogLevel.Action);
-				pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.EMPTY_DIRECTORY)));
-			} else {
-				logger.writeTCP("Sending LIST_RESPONSE", LogLevel.Action);
-				pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketTCP((Payload)(new FileList(fileList))));
-			}
-		} catch (Exception e2) {
-			logger.writeTCP(e2, LogLevel.Error);
-		}
+	protected Object getTrackerSocket() {
+		return (Object)tracker.getTCPSocket();
 	}
-
-	/** Send hash response to hash request
-	 * @param pd	Request received
-	 */
-	private void sendHashResponse(ProtocolP2PPacketTCP pd) {
-		Payload p = pd.getPayload();
-		assert p instanceof HashRequest : "payload must be an instance of HashRequest";
-		if (!(p instanceof HashRequest)) {
-			sendInternalError(pd);
-		} else {
-			String filename = ((HashRequest)p).getFilename();
-			if (Arrays.binarySearch(fileList, filename) >= 0) {
-				Map<HashAlgorithm, byte[]> hashes = new HashMap<>();
-				for (HashAlgorithm h : ((HashRequest)p).getAlgoList()) {
-					switch (h) {
-						case SHA512:
-							hashes.put(h, sha512.get(filename));
-							break;
-						case MD5:
-						default:
-							hashes.put(h, new byte[0]);
-							break;
-					}
-				}
-				try {
-					pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketTCP((Payload)(new HashResponse(filename, hashes))));
-				} catch (Exception e) {
-					logger.writeTCP(e, LogLevel.Error);
-				}
-			} else {
-				// file not found
-				try {
-					pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.NOT_FOUND)));
-				} catch (Exception e) {
-					logger.writeTCP(e, LogLevel.Error);
-				}
-			}
-		}
-	}
-			
-
-	/** Send response to load request
-	 * @param pd	Request received
-	 */
-	private void sendLoadResponse(ProtocolP2PPacketTCP pd) {
-		Payload p = pd.getPayload();
-		assert p instanceof LoadRequest : "payload must be an instance of LoadRequest";
-		if (!(p instanceof LoadRequest)) {
-			sendInternalError(pd);
-		} else {
-			String filename = ((LoadRequest)p).getFilename();
-			long offset = ((LoadRequest)p).getOffset();
-			long maxSizePartialContent = ((LoadRequest)p).getMaxSizePartialContent();
-			try {
-				byte[] fullLoad = Files.readAllBytes(Paths.get(baseDirectory + filename));
-				long sizeToSend = 0;
-				if (fullLoad.length - offset < maxSizePartialContent) {
-					logger.writeTCP("Sending last partialContent", LogLevel.Debug);
-					sizeToSend = fullLoad.length - offset;
-				} else {
-					sizeToSend = maxSizePartialContent;
-				}
-				logger.writeTCP("maxSizePartialContent: " + maxSizePartialContent, LogLevel.Debug);
-				logger.writeTCP("Sending " + filename + " from " + offset + " to " + (offset + sizeToSend), LogLevel.Debug);
-				byte[] load = Arrays.copyOfRange(fullLoad, (int)offset, (int)(offset + sizeToSend));
-				if (Arrays.binarySearch(fileList, filename) >= 0) {
-					try {
-						if (load.length == 0) {
-							pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.EMPTY_FILE)));
-						} else {
-							pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketTCP((Payload)(new FilePart(filename, fullLoad.length, offset, load))));
-						}
-					} catch (Exception e2) {
-						logger.writeTCP(e2, LogLevel.Error);
-					}
-				} else {
-					logger.writeTCP("File requested not found: `" + filename + "` " + Arrays.binarySearch(fileList, filename), LogLevel.Debug);
-					logger.writeTCP("File list:", LogLevel.Debug);
-					for (String f: fileList) {
-						logger.writeTCP("- " + f, LogLevel.Debug);
-					}
-
-					throw new IOException(); // to send a NOT_FOUND in the catch block
-				}
-			} catch (IOException e) {
-				try {
-					pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketTCP(new Payload(RequestResponseCode.NOT_FOUND)));
-				} catch (Exception e2) {
-					logger.writeTCP(e2, LogLevel.Debug);
-				}
-			}
-		}
-	}
-
 }

src/serverP2P/ServerManagementUDP.java

@@ -16,18 +16,13 @@ import protocolP2P.Payload;
 import protocolP2P.LoadRequest;
 import protocolP2P.FileList;
 import protocolP2P.FilePart;
-import exception.InternalError;
-import exception.ProtocolError;
-import exception.SizeError;
-import exception.TransmissionError;
-import exception.VersionError;
-import exception.SocketClosed;
-import remoteException.EmptyDirectory;
-import remoteException.InternalRemoteError;
-import remoteException.NotFound;
-import remoteException.ProtocolRemoteError;
-import remoteException.VersionRemoteError;
-import remoteException.EmptyFile;
+import localException.InternalError;
+import localException.ProtocolError;
+import localException.SizeError;
+import localException.TransmissionError;
+import localException.VersionError;
+import localException.SocketClosed;
+import exception.LocalException;
 import java.util.Arrays;
 import tools.Logger;
 import tools.LogLevel;
@@ -36,6 +31,11 @@ import java.util.Map;
 import protocolP2P.HashAlgorithm;
 import protocolP2P.HashRequest;
 import protocolP2P.HashResponse;
+import tools.HostItem;
+import protocolP2P.Register;
+import protocolP2P.Unregister;
+import java.net.UnknownHostException;
+import serverP2P.ServerManagement;
 
 /** Implementation of P2P-JAVA-PROJECT VERSION 1.0 protocol for UDP.
  * @author	Louis Royer
@@ -43,206 +43,77 @@ import protocolP2P.HashResponse;
  * @author	JS Auge
  * @version	1.0
  */
-public class ServerManagementUDP implements Runnable {
+public class ServerManagementUDP extends ServerManagement {
 
-	private String[] fileList;
-	private Map<String, byte[]> sha512 = new HashMap<>();
-	private String baseDirectory;
-	private int UDPPort;
 	private DatagramSocket socket;
-	private Logger logger;
 
 	/** Constructor for UDP implementation, with baseDirectory and UDPPort parameters.
 	 * @param baseDirectory	the root directory where files are stored
-	 * @param UDPPort	the server will listen on this port
+	 * @param hostName	the server will bind on this address
+	 * @param port	the server will listen on this port
+	 * @param logger	Logger item
+	 * @param tracker	Tracker
 	 */
-	public ServerManagementUDP(String baseDirectory, int UDPPort, Logger logger) {
-		this.logger = logger;
-		this.baseDirectory = baseDirectory;
-		this.UDPPort = UDPPort;
-		initFileList();
-		initSha512();
+	public ServerManagementUDP(String baseDirectory, HostItem server, HostItem tracker, Logger logger) {
+		super(baseDirectory, server, tracker, logger);
+		assert baseDirectory != null : "baseDirectory is null";
+		assert server != null : "server is null";
+		assert tracker != null : "tracker is null";
+		assert logger != null : "logger is null";
 		try {
-			socket = new DatagramSocket(UDPPort);
+			socket = new DatagramSocket(server.getPort(), server.getInetAddress());
 		} catch (SocketException e) {
-			logger.writeUDP("Error: cannot listen on port " + UDPPort, LogLevel.Error);
+			logger.writeUDP("Error: cannot listen on " + server, LogLevel.Error);
 			System.exit(-1);
 		}
 	}
 
+
 	/** Implementation of runnable. This methods allows to run the server.
 	 */
 	public void run() {
 		logger.writeUDP("Server sucessfully started", LogLevel.Info);
-		while(true) {
+		fileListWatcher = (FileWatcher)new FileWatcherUDP(logger, 10000, server, tracker, baseDirectory); // checking every 10 seconds
+		(new Thread(fileListWatcher)).start();
+		while(!stop) {
 			try {
-				ProtocolP2PPacketUDP pd = new ProtocolP2PPacketUDP((Object)socket);
-				Payload p = pd.getPayload();
-				switch (p.getRequestResponseCode()) {
-					case LOAD_REQUEST:
-						logger.writeUDP("Received LOAD_REQUEST", LogLevel.Action);
-						assert p instanceof LoadRequest : "payload must be an instance of LoadRequest";
-						if (!(p instanceof LoadRequest)) {
-							sendInternalError(pd);
-						} else {
-							String filename = ((LoadRequest)p).getFilename();
-							long offset = ((LoadRequest)p).getOffset();
-							long maxSizePartialContent = ((LoadRequest)p).getMaxSizePartialContent();
-							try {
-								byte[] fullLoad = Files.readAllBytes(Paths.get(baseDirectory + filename));
-								long sizeToSend = 0;
-								if (fullLoad.length - offset < maxSizePartialContent) {
-									logger.writeUDP("Sending last partialContent", LogLevel.Debug);
-									sizeToSend = fullLoad.length - offset;
-								} else {
-									sizeToSend = maxSizePartialContent;
-								}
-								logger.writeUDP("maxSizePartialContent: " + maxSizePartialContent, LogLevel.Debug);
-								logger.writeUDP("Sending " + filename + " from " + offset + " to " + (offset + sizeToSend), LogLevel.Debug);
-								byte[] load = Arrays.copyOfRange(fullLoad, (int)offset, (int)(offset + sizeToSend));
-								if (Arrays.binarySearch(fileList, filename) >= 0) {
-									try {
-										if (load.length == 0) {
-											pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.EMPTY_FILE)));
-										} else {
-											pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP((Payload)(new FilePart(filename, fullLoad.length, offset, load))));
-										}
-									} catch (Exception e2) {
-										logger.writeUDP(e2, LogLevel.Error);
-									}
-								} else {
-									logger.writeUDP("File requested not found: `" + filename + "` " + Arrays.binarySearch(fileList, filename), LogLevel.Debug);
-									logger.writeUDP("File list:", LogLevel.Debug);
-									for (String f: fileList) {
-										logger.writeUDP("- " + f, LogLevel.Debug);
-									}
-									
-									throw new IOException(); // to send a NOT_FOUND in the catch block
-								}
-							} catch (IOException e) {
-								try {
-									pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.NOT_FOUND)));
-								} catch (Exception e2) {
-									logger.writeUDP(e2, LogLevel.Error);
-								}
-							}
-						}
-						break;
-					case LIST_REQUEST:
-						logger.writeUDP("Received LIST_REQUEST", LogLevel.Action);
-						try {
-							if (fileList.length == 0) {
-								logger.writeUDP("Sending EMPTY_DIRECTORY", LogLevel.Action);
-								pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.EMPTY_DIRECTORY)));
-							} else {
-								logger.writeUDP("Sending LIST_RESPONSE", LogLevel.Action);
-								pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP((Payload)(new FileList(fileList))));
-							}
-						} catch (Exception e2) {
-							logger.writeUDP(e2, LogLevel.Error);
-						}
-						break;
-					case HASH_REQUEST:
-						logger.writeUDP("Received HASH_REQUEST", LogLevel.Action);
-						sendHashResponse(pd);
-						break;
-					default:
-						sendInternalError(pd);
-				}
+				ProtocolP2PPacketUDP<?> pd = new ProtocolP2PPacketUDP<>((Object)socket);
+				handleRequest(pd);
 			} catch (IOException e) {
-			} catch (SocketClosed e) {
-			} catch (TransmissionError e) {
-			} catch (ProtocolError e) {
-			} catch (VersionError e) {
-			} catch (InternalError e) {
-			} catch (SizeError e) {
+			} catch (LocalException e) {
 			}
 		}
+		fileListWatcher.setStop();
+		sendUnregisterRequest();
 	}
 
-	/** Initialize local list of all files allowed to be shared.
+
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
 	 */
-	private void initFileList() {
-		File folder = new File(baseDirectory);
-		Vector<String> v = new Vector<String>();
-		File[] files = folder.listFiles();
-		/* Add non-recursively files's names to fileList */
-		for (File f : files) {
-			if (f.isFile()) {
-				v.add(f.getName());
-			}
-		}
-		fileList = new String[v.size()];
-		v.toArray(fileList);
-		Arrays.sort(fileList);
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeUDP(text, logLevel);
 	}
 
-	/** Init sha512 map.
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
 	 */
-	 private void initSha512() {
-		for(String f: fileList) {
-			try {
-				MessageDigest md = MessageDigest.getInstance(HashAlgorithm.SHA512.getName()); 
-				sha512.put(f, md.digest(Files.readAllBytes(Paths.get(baseDirectory + f))));
-				md.reset();
-			} catch (NoSuchAlgorithmException e) {
-				logger.writeUDP("sha512 not supported", LogLevel.Error);
-			} catch (IOException e) {
-				logger.writeUDP("cannot read " + f, LogLevel.Warning);
-			}
-		}
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeUDP(e, logLevel);
 	}
-	
-	/** Send an internal error message.
-	 * @param pd	ProtocolP2PPacketUDP to respond
+
+	/** Create packets
+	 * @param payload	Payload
 	 */
-	private void sendInternalError(ProtocolP2PPacketUDP pd) {
-		logger.writeUDP("Internal Error", LogLevel.Warning);
-		try {
-			pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.INTERNAL_ERROR)));
-		} catch (Exception e) {
-			logger.writeUDP(e, LogLevel.Error);
-		}
+	protected < T extends Payload > ProtocolP2PPacket<T> createProtocolP2PPacket(T payload) {
+		return (ProtocolP2PPacket<T>)new ProtocolP2PPacketUDP<T>(payload);
 	}
 
-	/** Send hash response to hash request
-	 * @param pd	Request received
+	/** Getter for tracker socket
 	 */
-	private void sendHashResponse(ProtocolP2PPacketUDP pd) {
-		Payload p = pd.getPayload();
-		assert p instanceof HashRequest : "payload must be an instance of HashRequest";
-		if (!(p instanceof HashRequest)) {
-			sendInternalError(pd);
-		} else {
-			String filename = ((HashRequest)p).getFilename();
-			if (Arrays.binarySearch(fileList, filename) >= 0) {
-				Map<HashAlgorithm, byte[]> hashes = new HashMap<>();
-				for (HashAlgorithm h : ((HashRequest)p).getAlgoList()) {
-					switch (h) {
-						case SHA512:
-							hashes.put(h, sha512.get(filename));
-							break;
-						case MD5:
-						default:
-							hashes.put(h, new byte[0]);
-							break;
-					}
-				}
-				try {
-					pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP((Payload)(new HashResponse(filename, hashes))));
-				} catch (Exception e) {
-					logger.writeUDP(e, LogLevel.Error);
-				}
-			} else {
-				// file not found
-				try {
-					pd.sendResponse((ProtocolP2PPacket)new ProtocolP2PPacketUDP(new Payload(RequestResponseCode.NOT_FOUND)));
-				} catch (Exception e) {
-					logger.writeUDP(e, LogLevel.Error);
-				}
-			}
-		}
+	protected Object getTrackerSocket() {
+		return (Object)tracker.getUDPSocket();
 	}
-
 }
-

src/serverP2P/ServerP2P.java

@@ -1,8 +1,14 @@
 package serverP2P;
+
+import java.util.Scanner;
 import serverP2P.ServerManagementUDP;
 import serverP2P.ServerManagementTCP;
 import tools.Directories;
 import tools.Logger;
+import tools.HostItem;
+import tools.ServerPortRange;
+import tools.TrackerPortRange;
+
 
 /** Server only implementation
  * First argument of main method is port listened by the server, and is mandatory.
@@ -12,38 +18,111 @@ import tools.Logger;
  * @version	1.0
  */
 public class ServerP2P {
-	private int port;
 	private Directories directories;
 	static private final String subdir = "seeded/";
 	private Logger logger;
+	private HostItem tracker;
+	private HostItem server;
 
-	/** Constructor with portStr containing a port number.
-	 * @param portStr	String containing port number of listening.
+	/** Constructor with portServerstr containing a port number.
+	 * @param hostnameServer	binded hostname
+	 * @param portServer	binded port
+	 * @param hostnameTracker	tracker hostname
+	 * @param portTracker	tracker port
 	 */
-	public ServerP2P(String portStr) {
-		port = Integer.valueOf(Integer.parseInt(portStr));
-		directories = new Directories("P2P_JAVA_PROJECT_SERVER_" + port);
+	public ServerP2P(String hostnameServer, int portServer, String hostnameTracker, int portTracker) {
+		Scanner scanner = new Scanner(System.in);
+		server = new HostItem(hostnameServer, portServer);
+		tracker = new HostItem(hostnameTracker, portTracker);
+		directories = new Directories("P2P_JAVA_PROJECT_SERVER_" + portServer);
 		directories.createSubdir(subdir);
 		logger = new Logger(directories.getDataHomeDirectory() + "server.log");
-		System.out.println("Server will listen on port " + port + " and serve files from " + directories.getDataHomeDirectory() + subdir);
-		directories.askOpenDataHomeDirectory(subdir);
+		System.out.println("Server will listen on port " + portServer + " and serve files from " + directories.getDataHomeDirectory() + subdir);
+		directories.askOpenDataHomeDirectory(subdir, scanner);
+		scanner.close();
 	}
 
 	/** Main program entry point
 	 * first parameter is port number and is mandatory
-	 * to test, run with: java -ea serverP2P.ServerP2P -- <portNumber>
+	 * to test, run with: java serverP2P.ServerP2P
 	 * @param args	parameters
 	 */
 		public static void main(String [] args) {
-		ServerP2P s = new ServerP2P(args[1]);
-		ServerManagementUDP smudp = new ServerManagementUDP(s.directories.getDataHomeDirectory() + subdir, s.port, s.logger);
-		ServerManagementTCP smtcp = new ServerManagementTCP(s.directories.getDataHomeDirectory() + subdir, s.port, s.logger);
-		Thread tudp = new Thread(smudp);
-		tudp.setName("server UDP P2P-JAVA-PROJECT");
-		tudp.start();
-		Thread ttcp = new Thread(smtcp);
-		ttcp.setName("server TCP P2P-JAVA-PROJECT");
-		ttcp.start();
-	}
+			final String defaultHostname = "localhost";
+			final ServerPortRange serverPortRange = new ServerPortRange();
+			final TrackerPortRange trackerPortRange = new TrackerPortRange();
+			String hostnameServer = "";
+			int portServer = 0;
+			String hostnameTracker = "";
+			int portTracker = 0;
+			Scanner scanner = new Scanner(System.in);
+
+			if ((args.length != 5) && (args.length != 0)){
+				System.out.println("usage : java serveurP2P.ServeurP2P (interactive) or java serveurP2P.ServeurP2P -- <serveurHOSTNAME> <serveurPORT> <trackerHOSTNAME> <trackerPORT> (" + serverPortRange + " and " + trackerPortRange +")");
+				System.exit(1);
+			}
+			else if(args.length == 5){
+					hostnameServer = args[1];
+					portServer = Integer.valueOf(Integer.parseInt(args[2]));
+					hostnameTracker = args[3];
+					portTracker = Integer.valueOf(Integer.parseInt(args[4]));
+			} else {
+				System.out.println("Server, enter hostname to bind (default = localhost): ");
+				hostnameServer = scanner.nextLine();
+				if(hostnameServer.equals("")){
+					hostnameServer = defaultHostname;
+					System.out.println("using default hostname : " + hostnameServer);
+				}
+				System.out.println("enter port (default = " + serverPortRange.getDefaultPort() + "): ");
+				String portServerStr = scanner.nextLine();
+				if(portServerStr.equals("")){
+					portServer = serverPortRange.getDefaultPort();
+					System.out.println("using default port : " + portServer);
+				} else {
+					portServer = Integer.valueOf(Integer.parseInt(portServerStr));
+				}
+				System.out.println("enter hostname of tracker (default = localhost): ");
+				hostnameTracker = scanner.nextLine();
+				if(hostnameTracker.equals("")){
+					hostnameTracker = defaultHostname;
+					System.out.println("tracker default hostname : " + hostnameTracker);
+				}
+				System.out.println("enter tracker's port (default = " + trackerPortRange.getDefaultPort() + "): ");
+				String portTrackerStr = scanner.nextLine();
+				if(portTrackerStr.equals("")){
+					portTracker = serverPortRange.getDefaultPort();
+					System.out.println("using default port : " + portTracker);
+				} else {
+					portTracker = Integer.valueOf(Integer.parseInt(portTrackerStr));
+				}
+			}
+
+			System.out.println("using hostname : " + hostnameServer);
+			if(serverPortRange.isPortInRange(portServer)) {
+				System.out.println("using port : " + portServer);
+			}
+			else {
+				System.out.println("Port not in range. " + serverPortRange);
+				portServer = serverPortRange.getDefaultPort();
+			}
+			System.out.println("tracker hostname : " + hostnameTracker);
+
+			if(trackerPortRange.isPortInRange(portTracker)) {
+				System.out.println("using port : " + portTracker);
+			}
+			else {
+				System.out.println("Port not in range. " + trackerPortRange);
+				portTracker = trackerPortRange.getDefaultPort();
+			}
 
+			ServerP2P s = new ServerP2P(hostnameServer, portServer, hostnameTracker, portTracker);
+			ServerManagementUDP smudp = new ServerManagementUDP(s.directories.getDataHomeDirectory() + subdir, s.server, s.tracker, s.logger);
+			ServerManagementTCP smtcp = new ServerManagementTCP(s.directories.getDataHomeDirectory() + subdir, s.server, s.tracker, s.logger);
+			Thread tudp = new Thread(smudp);
+			tudp.setName("server UDP P2P-JAVA-PROJECT");
+			tudp.start();
+			Thread ttcp = new Thread(smtcp);
+			ttcp.setName("server TCP P2P-JAVA-PROJECT");
+			ttcp.start();
+		}
 }

src/tools/BytesArrayTools.java

@@ -1,6 +1,6 @@
 package tools;
-import exception.SizeError;
-import exception.ProtocolError;
+import localException.SizeError;
+import localException.ProtocolError;
 import java.io.UnsupportedEncodingException;
 import java.util.Arrays;
 
@@ -219,6 +219,39 @@ public class BytesArrayTools {
 		}
 	}
 
+	/** Read string from byte array
+	 * @param array	Byte array to read
+	 * @param start	start position in byte array
+	 * @param endStr	End string delimiter
+	 * @return	String read
+	 * @throws	InternalError
+	 */
+	public static String readString(byte[] array, int start, String endStr) throws InternalError {
+		boolean failed = false;
+		try {
+			int i = start;
+			while(true) {
+				int j = i;
+				for(byte b: endStr.getBytes()) {
+					if (b != array[j]) {
+						failed = true;
+						break;
+					}
+					j++;
+				}
+				if (failed) {
+					i++;
+					failed = false;
+				} else {
+					break;
+				}
+			}
+			return readString(array, start, i - start);
+		} catch(IndexOutOfBoundsException e) {
+			throw new InternalError();
+		}
+	}
+
 	/** Write byte Array to byte Array.
 	 * @param dst	Destination byte Array
 	 * @param src	Source byte Array

src/tools/Directories.java

@@ -70,6 +70,7 @@ public class Directories {
 	}
 
 	/** Opens dataHomeDirectory if supported.
+	 * @param subdir	Subdir to open (optional)
 	 */
 	private void openDataHomeDirectory(String subdir) {
 		String d = dataHomeDirectory;
@@ -93,11 +94,12 @@ public class Directories {
 	}
 
 	/** Asks the user to choose opening dataHomeDirectory or not.
+	 * @param subdir	subdirectory to open (optional)
+	 * @param scanner	Scanner to use for reading input
 	 */
-	public void askOpenDataHomeDirectory(String subdir) {
+	public void askOpenDataHomeDirectory(String subdir, Scanner scanner) {
 		if (os.equals("Linux") || os.equals("Mac") || os.equals("Mac OS X")) {
 			System.out.println("Do you want to open this directory? (y/N)");
-			Scanner scanner = new Scanner(System.in);
 			String resp = scanner.nextLine();
 			if (resp.equals("y") || resp.equals("Y")) {
 				System.out.println("Openning");

src/tools/HostItem.java

@@ -17,6 +17,7 @@ public class HostItem {
 	private int port;
 	private Socket tcpSocket;
 	private DatagramSocket udpSocket;
+	private InetAddress inetAddress;
 
 	/** Constructor with hostname and port
 	 * @param hostname	Hostname
@@ -35,19 +36,32 @@ public class HostItem {
 			try {
 				tcpSocket = new Socket(InetAddress.getByName(hostname), port);
 			} catch (SocketException e) {
-				System.err.println("Error: No TCP socket available.");
+				System.err.println("getTCPSocket error: No TCP socket available.");
 				System.exit(-1);
 			} catch (UnknownHostException e) {
-				System.err.println("Error: Unknown host.");
+				System.err.println("getTCPSocket error: Unknown host (" + this + ").");
 				System.exit(-1);
 			} catch (IOException e) {
-				System.err.println("Error: Cannot create TCP socket");
+				System.err.println("getTCPSocket error: Cannot create TCP socket (" + this + ").");
 				System.exit(-1);
 			}
 		}
 		return tcpSocket;
 	}
 
+	/** Get TCP Socket.
+	 * @return	TCP Socket
+	 * @throws	SocketException
+	 * @throws	UnknownHostException
+	 * @throws	IOException
+	 */
+	public Socket tryGetTCPSocket() throws SocketException, UnknownHostException, IOException {
+		if (tcpSocket == null) {
+			tcpSocket = new Socket(InetAddress.getByName(hostname), port);
+		}
+		return tcpSocket;
+	}
+
 	/** Closes tcp socket
 	 */
 	public void closeTCPSocket() {
@@ -70,19 +84,86 @@ public class HostItem {
 				udpSocket = new DatagramSocket();
 				udpSocket.connect(InetAddress.getByName(hostname), port);
 			} catch (SocketException e) {
-				System.err.println("Error: No UDP socket available.");
+				System.err.println("getUDPSocket error: No UDP socket available." );
 				System.exit(-1);
 			} catch (UnknownHostException e) {
-				System.err.println("Error: Unknown host.");
+				System.err.println("getUDPSocket error: Unknown host (" + this + ").");
 				System.exit(-1);
 			}
 		}
 		return udpSocket;
 	}
+
+	/** Closes udp socket
+	 */
 	public void closeUDPSocket() {
 		if (udpSocket != null) {
 			udpSocket.close();
 		}
 		udpSocket = null;
 	}
+
+	/** Getter for hostname */
+	public String getHostname() {
+		return hostname;
+	}
+
+	/** Getter for port */
+	public int getPort() {
+		return port;
+	}
+
+	/** To string
+	 * @return	String representation
+	 */
+	public String toString() {
+		return getHostname() + " (port " + getPort() + ")";
+	}
+
+	/** Override of equals method
+	 * @param other	Object to test equality with
+	 * @return	true if equals
+	 */
+	public boolean equals(Object other) {
+		boolean result = false;
+		if (other instanceof HostItem) {
+			HostItem that = (HostItem) other;
+			result = this.getHostname() == that.getHostname() && this.getPort() == that.getPort();
+		}
+		return result;
+	}
+
+	/** Override of hashCode method
+	 * @return	a hash code for this object.
+	 */
+	public int hashCode() {
+		return hostname.hashCode() ^ port;
+	}
+
+	/** Get InetAddress associated to this HostItem.
+	 * @return	InetAddress
+	 */
+	public InetAddress getInetAddress() {
+		if (inetAddress == null) {
+			try {
+				inetAddress = InetAddress.getByName(getHostname());
+			} catch (UnknownHostException e) {
+				System.err.println("getInetAddress error: Unknown host (" + this + ").");
+				System.exit(-1);
+			}
+		}
+		return inetAddress;
+	}
+
+	/** Constructor from Socket.
+	 * @param s	socket
+	 */
+	public HostItem(Socket s) {
+		tcpSocket = s;
+		inetAddress = s.getInetAddress();
+		hostname = inetAddress.getCanonicalHostName();
+		port = s.getPort();
+	}
+
+	
 }

src/tools/HostList.java

@@ -1,55 +0,0 @@
-package tools;
-
-import java.util.Scanner;
-import java.util.ArrayList;
-import java.util.List;
-import java.util.InputMismatchException;
-import tools.HostItem;
-
-/** Helper to get the server list from the user
-* @author	Louis Royer
-* @author	Flavien Haas
-* @author	JS Auge
-* @version	1.0
-*/
-public class HostList {
-	/**
-	* Let the user enter all server and puts it in a list
-	* @return list of servers
-	*/
-	public static List<HostItem> getServList() {
-		List<HostItem> serverList = new ArrayList<HostItem>();
-		Scanner scanner = new Scanner(System.in);
-		String servName;
-		int port = 0;
-		do {
-			System.out.println("Enter hostname of next server: (or \"stop\" when finished, default: localhost).");
-			servName = scanner.nextLine();
-			if (servName.equals("")) {
-				servName = "localhost";
-			}
-			if (!servName.equals("stop")) {
-				boolean err = false;
-				do {
-					System.out.println("Enter port for this server");
-					try {
-						port = scanner.nextInt();
-						scanner.nextLine();
-						if (port > 65535 || port <= 0) {
-							err = true;
-							System.out.println("Port number must be in 1-65535 range. Try again.");
-						} else {
-							err = false;
-						}
-					} catch (InputMismatchException e) {
-						System.out.println("Invalid number. Try again.");
-						err = true;
-					}
-				} while (err);
-				serverList.add(new HostItem(servName, port));
-			}
-			
-		} while (!servName.equals("stop"));
-		return serverList;
-	}
-}

src/tools/Logger.java

@@ -17,6 +17,9 @@ import java.sql.Timestamp;
 public class Logger {
 	private Path logFile;
 
+	/** Constructor with logFile.
+	 * @param logFile	name of the file to store logs.
+	 */
 	public Logger(String logFile) {
 		assert logFile != null : "Logfile name is null";
 		this.logFile = Paths.get(logFile);
@@ -120,4 +123,5 @@ public class Logger {
 		e.printStackTrace();
 	}
 
+
 }

src/tools/PortRange.java

@@ -0,0 +1,49 @@
+package tools;
+
+/** Test ports.
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public class PortRange {
+
+	protected int portMax;
+	protected int portMin;
+	protected int defaultPort;
+	protected String type;
+
+	/** Port range constructor
+	 * @param portMin	minimum port
+	 * @param portMax	maximum port
+	 * @param defaultPort	default port
+	 * @param type	type of range
+	 */
+	public PortRange(int portMin, int portMax, int defaultPort, String type) {
+		this.portMax = portMax;
+		this.portMin = portMin;
+		this.defaultPort = defaultPort;
+		this.type = type;
+	}
+
+	/** test if port given correspond a range : registered ports, can be used without superuser privileges
+	 * @return	true if port was valid
+	 */
+	public boolean isPortInRange(int port) {
+		return ((port >= portMin) && (port <= portMax));
+	}
+
+	/** To String
+	 * @return String representation
+	 */
+	 public String toString() {
+		 return "default " + type + "port: " + defaultPort + "(range: " + portMin + " -> " + portMax + ")";
+	 }
+
+	/** Default port getter
+	 * @return	default port
+	 */
+	 public int getDefaultPort() {
+		 return defaultPort;
+	 }
+}

src/tools/ServeErrors.java

@@ -0,0 +1,82 @@
+package tools;
+import tools.LogLevel;
+import protocolP2P.ProtocolP2PPacket;
+import protocolP2P.Payload;
+import protocolP2P.RequestResponseCode;
+
+public abstract class ServeErrors {
+
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
+	 */
+	protected abstract void writeLog(String text, LogLevel logLevel);
+
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
+	 */
+	protected abstract void writeLog(Exception e, LogLevel logLevel);
+
+	/** Create packets
+	 * @param payload	Payload
+	 */
+	protected abstract < T extends Payload > ProtocolP2PPacket<?> createProtocolP2PPacket(T payload);
+
+	/** Send a NotATracker error message.
+	 * @param pd	Request received
+	 */
+	protected < T extends ProtocolP2PPacket<?> > void sendNotATracker(T pd) {
+		try {
+			pd.sendResponse(createProtocolP2PPacket(new Payload(RequestResponseCode.NOT_A_TRACKER)));
+		} catch (Exception e) {
+			writeLog(e, LogLevel.Error);
+		}
+	}
+
+	/** Send an internal error message.
+	 * @param pd	Request received
+	 */
+	protected < T extends ProtocolP2PPacket<?> > void sendInternalError(T pd) {
+		writeLog("Internal Error", LogLevel.Warning);
+		try {
+			pd.sendResponse(createProtocolP2PPacket(new Payload(RequestResponseCode.INTERNAL_ERROR)));
+		} catch (Exception e) {
+			writeLog(e, LogLevel.Error);
+		}
+	}
+
+	/** Send a not found message.
+	 * @param pd	Request received
+	 */
+	protected < T extends ProtocolP2PPacket<?> > void sendNotFound(T pd) {
+		try {
+			pd.sendResponse(createProtocolP2PPacket(new Payload(RequestResponseCode.NOT_FOUND)));
+		} catch (Exception e) {
+			writeLog(e, LogLevel.Error);
+		}
+	}
+
+	/** Send an empty directory message.
+	 * @param pd	Request received
+	 */
+	protected < T extends ProtocolP2PPacket<?> > void sendEmptyDirectory(T pd) {
+		try {
+			pd.sendResponse(createProtocolP2PPacket(new Payload(RequestResponseCode.EMPTY_DIRECTORY)));
+		} catch (Exception e) {
+			writeLog(e, LogLevel.Error);
+		}
+	}
+
+	/** Send an empty file message.
+	 * @param pd	Request received
+	 */
+	protected < T extends ProtocolP2PPacket<?> > void sendEmptyFile(T pd) {
+		try {
+			pd.sendResponse(createProtocolP2PPacket(new Payload(RequestResponseCode.EMPTY_FILE)));
+		} catch (Exception e) {
+			writeLog(e, LogLevel.Error);
+		}
+	}
+
+}

src/tools/ServerPortRange.java

@@ -0,0 +1,10 @@
+package tools;
+import tools.PortRange;
+
+public class ServerPortRange extends PortRange {
+
+	/** Constructor */
+	public ServerPortRange() {
+		super(7000, 7999, 7070, "server");
+	}
+}

src/tools/TrackerPortRange.java

@@ -0,0 +1,10 @@
+package tools;
+import tools.PortRange;
+
+public class TrackerPortRange extends PortRange {
+
+	/** Constructor */
+	public TrackerPortRange() {
+		super(6000, 6999, 6969, "tracker");
+	}
+}

src/tracker/Tracker.java

@@ -0,0 +1,93 @@
+package tracker;
+
+import java.util.Scanner;
+import tracker.TrackerManagementTCP;
+import tracker.TrackerManagementUDP;
+import tools.Directories;
+import tools.Logger;
+import tools.LogLevel;
+import tools.TrackerPortRange;
+import tools.HostItem;
+
+/** Tracker implementation
+ * First argument of main method is port listened by the tracker, and is mandatory.
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public class Tracker {
+	private HostItem tracker;
+	private Directories directories;
+	private Logger logger;
+
+	/** Constructor with portStr containing a port number.
+	 * @param hostname	hostname to bind
+	 * @param port	port to bind
+	 */
+	public Tracker(String hostname, int port) {
+		tracker = new HostItem(hostname, port);
+		directories = new Directories("P2P_JAVA_PROJECT_TRACKER_" + port);
+		logger = new Logger(directories.getDataHomeDirectory() + "tracker.log");
+		System.out.println("Tracker will listen on port " + port + " and write logs into " + directories.getDataHomeDirectory());
+		Scanner scanner = new Scanner(System.in);
+		directories.askOpenDataHomeDirectory(null, scanner);
+		scanner.close();
+	}
+
+	/** Main program entry point
+	 * first parameter is port number and is mandatory
+	 * to test, run with: java serverP2P.ServerP2P
+	 * @param args	parameters
+	 */
+	public static void main(String [] args) {
+		final TrackerPortRange trackerPortRange = new TrackerPortRange();
+		final String defaultHostname = "localhost";
+		Scanner scanner = new Scanner(System.in);
+		String hostname = "";
+		int port = 0;
+		Tracker t;
+
+		if ((args.length != 3) && (args.length != 0)){
+			System.out.println("usage : java tracker.Tracker (interactive) or java trackerP2P.trackerP2P -- <hostname> <PORT> (" + trackerPortRange +")");
+			System.exit(1);
+		} else if (args.length == 3){
+				hostname = args[1];
+				port = Integer.valueOf(Integer.parseInt(args[2]));
+		} else {
+			System.out.println("Tracker Server, enter hostname to bind (default = localhost): ");
+			hostname = scanner.nextLine();
+			if(hostname.equals("")){
+				hostname = defaultHostname;
+				System.out.println("using default hostname : " + hostname);
+			}
+			System.out.println("enter port (default = " + trackerPortRange.getDefaultPort() +"): ");
+			String portStr = scanner.nextLine();
+			if(portStr.equals("")){
+				port = trackerPortRange.getDefaultPort();
+				System.out.println("using default port : " + port);
+			} else {
+				port = Integer.valueOf(Integer.parseInt(portStr));
+			}
+		}
+
+		System.out.println("using hostname : " + hostname);
+		if(trackerPortRange.isPortInRange(port)) {
+			System.out.println("using port : " + port);
+			t = new Tracker(hostname, port);
+		}
+		else {
+			System.out.println("Port not in range. " + trackerPortRange);
+			t = new Tracker(hostname, trackerPortRange.getDefaultPort());
+		}
+
+		TrackerManagementUDP tmudp = new TrackerManagementUDP(t.tracker, t.logger);
+		TrackerManagementTCP tmtcp = new TrackerManagementTCP(t.tracker, t.logger);
+		Thread tudp = new Thread(tmudp);
+		tudp.setName("Tracker UDP P2P-JAVA-PROJECT");
+		tudp.start();
+		Thread ttcp = new Thread(tmtcp);
+		ttcp.setName("Tracker TCP P2P-JAVA-PROJECT");
+		ttcp.start();
+	}
+}

src/tracker/TrackerManagement.java

@@ -0,0 +1,201 @@
+package tracker;
+import tools.ServeErrors;
+import tools.HostItem;
+import tools.Logger;
+import tools.LogLevel;
+import java.util.Map;
+import java.util.HashMap;
+import java.util.ArrayList;
+import java.util.List;
+import protocolP2P.ProtocolP2PPacket;
+import protocolP2P.Payload;
+import protocolP2P.DiscoverRequest;
+import protocolP2P.DiscoverResponse;
+import protocolP2P.FileList;
+import protocolP2P.Unregister;
+import protocolP2P.Register;
+import protocolP2P.RequestResponseCode;
+import localException.InternalError;
+import remoteException.EmptyDirectory;
+import exception.LocalException;
+
+
+/** Tracker management implementation
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public abstract class TrackerManagement extends ServeErrors implements Runnable {
+	protected HostItem tracker;
+	protected Logger logger;
+	protected List<HostItem> hostList = new ArrayList<>();
+	protected Map<String, List<HostItem>> fileList = new HashMap<>();
+	protected volatile boolean stop;
+
+	/** Constructor
+	 * @param tracker	Tracker HostItem
+	 * @param logger	Logger
+	 */
+	public TrackerManagement(HostItem tracker, Logger logger) {
+		stop = false;
+		this.tracker = tracker;
+		this.logger = logger;
+	}
+
+	/** Handle Discover request
+	 * @param pd	Received request
+	 * @throws	InternalError
+	 */
+	protected < T extends ProtocolP2PPacket<?> > void handleDiscover(T pd) throws InternalError {
+		Payload p = pd.getPayload();
+		assert p instanceof DiscoverRequest : "payload must be an instance of DiscoverRequest";
+		if (!(p instanceof DiscoverRequest)) {
+			sendInternalError(pd);
+		} else {
+			String filename = ((DiscoverRequest)p).getFilename();
+			try {
+				pd.sendResponse(createProtocolP2PPacket(new DiscoverResponse(filename, fileList.getOrDefault(filename, hostList))));
+			} catch (Exception e) {
+				writeLog(e, LogLevel.Error);
+			}
+		}
+	}
+
+	/** Handle List Responses
+	 * @param pd	Received response
+	 * @throws	InternalError
+	 */
+	protected <T extends ProtocolP2PPacket<?> > void handleListResponse(T pd, HostItem host) throws InternalError {
+		Payload p = pd.getPayload();
+		assert p instanceof FileList: "payload must be an instance of FileList";
+		if (!(p instanceof FileList)) {
+			throw new InternalError();
+		} else {
+			String[] f = ((FileList)p).getFileList();
+			for (String file: f) {
+				List<HostItem> h = fileList.get(file);
+				if (h != null) {
+					if (!h.contains(host)) {
+						h.add(host);
+					}
+				} else {
+					List<HostItem> emptyH = new ArrayList<>();
+					emptyH.add(host);
+					fileList.put(file, emptyH);
+				} 
+			}
+		}
+	}
+
+	/** Handle Unregistering
+	 * @param pd	Request received
+	 * @throws	InternalError
+	 */
+	protected < T extends ProtocolP2PPacket<?> > void handleUnregister(T pd) throws InternalError {
+		Payload p = pd.getPayload();
+		assert p instanceof Unregister : "payload must be an instance of Unregister";
+		if (!(p instanceof Unregister)) {
+			sendInternalError(pd);
+			throw new InternalError();
+		}
+		HostItem host = ((Unregister)p).getHostItem();
+		writeLog("Received UNREGISTER from host " + pd.getHostItem() + ". Removing host " + host, LogLevel.Action);
+		hostList.remove(host);
+		for(String f: fileList.keySet()) {
+			fileList.get(f).remove(host);
+			if(fileList.get(f).isEmpty()) {
+				fileList.remove(f);
+			}
+		}
+	}
+
+	/** Getter for HostItem socket
+	 * @param hostItem	HostItem
+	 */
+	protected abstract Object getHostItemSocket(HostItem hostItem);
+
+	/** Close HostItem socket
+	 * @param hostItem	HostItem
+	 */
+	protected abstract void closeHostItemSocket(HostItem hostItem);
+
+	/** Handle Registering
+	 * @param pd	Received request
+	 * @throws	InternalError
+	 */
+	protected < T extends ProtocolP2PPacket<?> > void handleRegister(T pd) throws InternalError {
+		Payload p = pd.getPayload();
+		assert p instanceof Register : "payload must be an instance of Register";
+		if (!(p instanceof Register)) {
+			throw new InternalError();
+		} 
+		// add host to known host list
+		HostItem host = ((Register)p).getHostItem();
+		if (!hostList.contains(host)) {
+			hostList.add(host);
+		}
+		// send a list request
+		try {
+			ProtocolP2PPacket<?> pLReq = createProtocolP2PPacket(new Payload(RequestResponseCode.LIST_REQUEST));
+			pLReq.sendRequest(getHostItemSocket(host));
+			writeLog("Received REGISTER from host " + pd.getHostItem() + ". Adding host " + host + " to list. Sending List request", LogLevel.Action);
+			handleListResponse(pLReq.receiveResponse(), host);
+			writeLog("Received LIST RESPONSE from host " + pd.getHostItem(), LogLevel.Action);
+			closeHostItemSocket(host);
+		} catch (EmptyDirectory e) {
+			writeLog("Empty Directory", LogLevel.Debug);
+			hostList.remove(host);
+			writeLog("Received EMPTY DIRECTORY from host " + pd.getHostItem() + ". Aborting.", LogLevel.Action);
+		} catch (Exception e) {
+			// remove from list because list request could not be send
+			hostList.remove(host);
+			writeLog("Aborting the add of host " + host, LogLevel.Action);
+			writeLog(e, LogLevel.Error);
+		}
+	}
+
+
+	/** Handle requests
+	 * @throws	LocalException
+	 */
+	protected <T extends ProtocolP2PPacket<?> > void handleRequest(T pd) throws LocalException {
+		Payload p = pd.getPayload();
+		switch (p.getRequestResponseCode()) {
+			case LOAD_REQUEST:
+				writeLog("Received LOAD_REQUEST from host " + pd.getHostItem() + ", sending NOT_FOUND", LogLevel.Action);
+				sendNotFound(pd);
+				break;
+			case LIST_REQUEST:
+				writeLog("Received LIST_REQUEST from host " + pd.getHostItem() + ", sending EMPTY_DIRECTORY", LogLevel.Action);
+				sendEmptyDirectory(pd);
+				break;
+			case HASH_REQUEST:
+				writeLog("Received HASH_REQUEST from host " + pd.getHostItem() + ", sending NOT_FOUND", LogLevel.Action);
+				sendNotFound(pd);
+				break;
+			case REGISTER:
+				writeLog("Received REGISTER from host " + pd.getHostItem(), LogLevel.Debug);
+				handleRegister(pd);
+				break;
+			case UNREGISTER:
+				writeLog("Received UNREGISTER from host " + pd.getHostItem(), LogLevel.Debug);
+				handleUnregister(pd);
+				break;
+			case DISCOVER_REQUEST:
+				writeLog("Received DISCOVER REQUEST from host " + pd.getHostItem(), LogLevel.Action);
+				handleDiscover(pd);
+				break;
+			default:
+				writeLog("Received grabbage from host " + pd.getHostItem(), LogLevel.Action);
+				sendInternalError(pd);
+				break;
+		}
+	}
+
+	/** Stop the thread */
+	public void setStop() {
+		stop = true;
+	}
+
+}

src/tracker/TrackerManagementTCP.java

@@ -0,0 +1,155 @@
+package tracker;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.HashMap;
+import java.io.IOException;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.net.SocketException;
+import java.net.UnknownHostException;
+import java.net.InetAddress;
+import protocolP2P.ProtocolP2PPacketTCP;
+import protocolP2P.ProtocolP2PPacket;
+import protocolP2P.RequestResponseCode;
+import protocolP2P.Payload;
+import protocolP2P.Register;
+import protocolP2P.Unregister;
+import protocolP2P.DiscoverRequest;
+import protocolP2P.DiscoverResponse;
+import protocolP2P.FileList;
+import exception.LocalException;
+import remoteException.EmptyDirectory;
+import localException.InternalError;
+import localException.SocketClosed;
+import tracker.TrackerManagement;
+import tools.HostItem;
+import tools.Logger;
+import tools.LogLevel;
+
+/** Tracker management implementation with tcp
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public class TrackerManagementTCP extends TrackerManagement {
+	private ServerSocket socket;
+
+	/** Constructor with port and logger.
+	 * @param tracker	hostitem of the tracker.
+	 * @param logger	Logger object
+	 */
+	public TrackerManagementTCP(HostItem tracker, Logger logger) {
+		super(tracker, logger);
+		try {
+			socket = new ServerSocket(tracker.getPort(), 10, tracker.getInetAddress());
+		} catch (SocketException e) {
+			writeLog("Error: cannot listen on" + tracker, LogLevel.Error);
+			System.exit(-1);
+		} catch (IOException e) {
+			writeLog("Error: cannot open socket", LogLevel.Error);
+			System.exit(-2);
+		}
+	}
+
+	/** Implementation of runnable. This methods allows to run the server.
+	 */
+	public void run() {
+		writeLog("Tracker sucessfully started", LogLevel.Info);
+		while (!stop) {
+			try {
+				Socket s = socket.accept();
+				ClientHandler c = new ClientHandler(s);
+				(new Thread(c)).start();
+			} catch (IOException e) {
+				writeLog("Error while accepting new connection", LogLevel.Warning);
+			}
+		}
+	}
+
+
+	/** Private runnable class allowing to serve one client.
+	 */
+	private class ClientHandler implements Runnable {
+		private HostItem addr;
+		/** Constructor with a socket.
+		 * @param	s	Socket of this client
+		 */
+		public ClientHandler(Socket s) {
+			this.addr = new HostItem(s);
+		}
+
+		/** Implementation of runnable. This method allow to serve one client.
+		 */
+		public void run() {
+
+			boolean end = false;
+			writeLog("[ " + addr + "] New connection", LogLevel.Action);
+			do {
+				end = handleClientRequest();
+			} while(!end);
+			writeLog("[ " + addr + "] End of connection", LogLevel.Action);
+		}
+
+		/** Respond to next request incomming on socket s.
+		 * @param s	Socket used to read request and send response
+		 * @return	true if cannot expect another request (ie, socket is closed)
+		 */
+		private boolean handleClientRequest() {
+			try {
+				ProtocolP2PPacketTCP<?> pd = new ProtocolP2PPacketTCP<>((Object)addr.getTCPSocket());
+				handleRequest(pd);
+			} catch (IOException e) {
+				writeLog(e, LogLevel.Warning);
+				return true;
+			} catch (SocketClosed e) {
+				return true;
+			} catch (LocalException e) {
+				writeLog(e, LogLevel.Warning);
+				return true;
+			}
+			return false;
+		}
+	}
+
+
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
+	 */
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeTCP(text, logLevel);
+	}
+
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
+	 */
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeTCP(e, logLevel);
+	}
+
+	/** Create packets
+	 * @param payload	Payload
+	 */
+	protected < T extends Payload > ProtocolP2PPacket<T> createProtocolP2PPacket(T payload) {
+		return (ProtocolP2PPacket<T>)new ProtocolP2PPacketTCP<T>(payload);
+	}
+
+	
+	/** Getter for HostItem socket
+	 * @param hostItem	HostItem
+	 */
+	protected Object getHostItemSocket(HostItem hostItem) {
+		return (Object)hostItem.getTCPSocket();
+	}
+	
+	/** Close HostItem socket
+	 * @param hostItem	HostItem
+	 */
+	protected void closeHostItemSocket(HostItem hostItem) {
+		hostItem.closeTCPSocket();
+	}
+}

src/tracker/TrackerManagementUDP.java

@@ -0,0 +1,103 @@
+package tracker;
+import tools.Logger;
+import tools.LogLevel;
+import java.net.DatagramSocket;
+import protocolP2P.ProtocolP2PPacketUDP;
+import protocolP2P.ProtocolP2PPacket;
+import protocolP2P.RequestResponseCode;
+import protocolP2P.Payload;
+import protocolP2P.Register;
+import protocolP2P.Unregister;
+import tools.HostItem;
+import java.util.ArrayList;
+import java.util.List;
+import java.io.IOException;
+import java.net.SocketException;
+import exception.LocalException;
+import java.util.Map;
+import java.util.HashMap;
+import protocolP2P.DiscoverRequest;
+import protocolP2P.DiscoverResponse;
+import protocolP2P.FileList;
+import localException.InternalError;
+import remoteException.EmptyDirectory;
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+import tracker.TrackerManagement;
+
+/** Tracker management implementation with udp
+ * @author	Louis Royer
+ * @author	Flavien Haas
+ * @author	JS Auge
+ * @version	1.0
+ */
+public class TrackerManagementUDP extends TrackerManagement {
+	private DatagramSocket socket;
+	/** Constructor with port and logger.
+	 * @param tracker	hostitem of the tracker.
+	 * @param logger	Logger object
+	 */
+	public TrackerManagementUDP(HostItem tracker, Logger logger) {
+		super(tracker, logger);
+		try {
+			socket = new DatagramSocket(tracker.getPort(), tracker.getInetAddress());
+		} catch (SocketException e) {
+			logger.writeUDP("Error: cannot listen on " + tracker, LogLevel.Error);
+			System.exit(-1);
+		}
+	}
+
+	/** Implementation of runnable. This methods allows to run the tracker.
+	 */
+	public void run() {
+		logger.writeUDP("Tracker successfully started", LogLevel.Info);
+		while(!stop) {
+			try {
+				ProtocolP2PPacketUDP<?> pd = new ProtocolP2PPacketUDP<>((Object)socket);
+				handleRequest(pd);
+			} catch (IOException e) {
+				logger.writeUDP(e, LogLevel.Warning);
+			} catch (LocalException e) {
+				logger.writeUDP(e, LogLevel.Warning);
+			}
+		}
+	}
+	
+	/** Implementation of writeLog
+	 * @param text	Text to log
+	 * @param logLevel	level of logging
+	 */
+	protected void writeLog(String text, LogLevel logLevel) {
+		logger.writeUDP(text, logLevel);
+	}
+
+	/** Implementation of writeLog
+	 * @param e	exception to log
+	 * @param logLevel	level of logging
+	 */
+	protected void writeLog(Exception e, LogLevel logLevel) {
+		logger.writeUDP(e, logLevel);
+	}
+
+	/** Create packets
+	 * @param payload	Payload
+	 */
+	protected < T extends Payload > ProtocolP2PPacket<T> createProtocolP2PPacket(T payload) {
+		return (ProtocolP2PPacket<T>)new ProtocolP2PPacketUDP<T>(payload);
+	}
+
+	
+	/** Getter for HostItem socket
+	 * @param hostItem	HostItem
+	 */
+	protected Object getHostItemSocket(HostItem hostItem) {
+		return (Object)hostItem.getUDPSocket();
+	}
+
+	/** Close HostItem socket
+	 * @param hostItem	HostItem
+	 */
+	protected void closeHostItemSocket(HostItem hostItem) {
+		hostItem.closeUDPSocket();
+	}
+}