Add send + receive methods

src/protocolP2P/FileList.java

@@ -2,6 +2,7 @@ package protocolP2P;
 import java.util.Arrays;
 import protocolP2P.Payload;
 import protocolP2P.RequestResponseCode;
+import exception.TransmissionError;
 import exception.ProtocolError;
 import exception.InternalError;
 import exception.SizeError;
@@ -36,8 +37,9 @@ public class FileList extends Payload {
 	 * @throws	SizeError
 	 * @throws	InternalError
 	 * @throws	ProtocolError
+	 * @throws	TransmissionError
 	 */
-	protected FileList(byte[] datagram) throws SizeError, ProtocolError, InternalError {
+	protected FileList(byte[] datagram) throws TransmissionError, SizeError, ProtocolError, InternalError {
 		super(datagram);
 		/* assert to help debugging */
 		assert requestResponseCode == RequestResponseCode.LIST_RESPONSE : "FileList subclass is incompatible with this datagram, request/response code must be checked before using this constructor";

src/protocolP2P/FilePart.java

@@ -4,6 +4,7 @@ import protocolP2P.RequestResponseCode;
 import exception.ProtocolError;
 import exception.InternalError;
 import exception.SizeError;
+import exception.TransmissionError;
 import tools.BytesArrayTools;
 import java.util.Arrays;
 import java.io.UnsupportedEncodingException;
@@ -49,8 +50,9 @@ public class FilePart extends Payload {
 	 * @param datagram	the full datagram received
 	 * @throws	SizeError
 	 * @throws	InternalError
+	 * @throws	TransmissionError
 	 */
-	protected FilePart(byte[] datagram) throws SizeError, ProtocolError, InternalError {
+	protected FilePart(byte[] datagram) throws TransmissionError, SizeError, ProtocolError, InternalError {
 		super(datagram);
 		/* assert to help debugging */
 		assert requestResponseCode == RequestResponseCode.LOAD_RESPONSE : "FilePart subclass is incompatible with this datagram, request/response code must be checked before using this constructor";

src/protocolP2P/Payload.java

@@ -4,6 +4,7 @@ import protocolP2P.FilePart;
 import protocolP2P.FileList;
 import exception.ProtocolError;
 import exception.InternalError;
+import exception.TransmissionError;
 import exception.SizeError;
 import tools.BytesArrayTools;
 /** Representation of payload. If payload has a size, use subclasses instead.
@@ -34,9 +35,15 @@ public class Payload {
 	 * @param datagram	the full datagram received
 	 * @throws	ProtocolError
 	 * @throws	InternalError
+	 * @throws	TransmissionError
+	 * @throws	SizeError
 	 */
-	protected Payload(byte[] datagram) throws ProtocolError, InternalError {
+	protected Payload(byte[] datagram) throws SizeError, ProtocolError, InternalError, TransmissionError {
 		/* asserts to help debugging */
+		assert getPayloadSize(datagram) + 8 <= datagram.length : "Payload is truncated";
+		if (datagram.length < getPayloadSize(datagram) + 8) {
+			throw new TransmissionError();
+		}
 		assert RequestResponseCode.fromCode(datagram[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.LIST_RESPONSE || (this instanceof FileList) : "LIST_RESPONSE must use FilePart class";
 		assert RequestResponseCode.fromCode(datagram[RequestResponseCode.RRCODE_POSITION]) != RequestResponseCode.LOAD_RESPONSE || (this instanceof FilePart) : "LOAD_RESPONSE must use FileList class";
 		requestResponseCode = RequestResponseCode.fromCode(datagram[RequestResponseCode.RRCODE_POSITION]);

src/protocolP2P/ProtocolP2PDatagram.java

@@ -3,12 +3,16 @@ import exception.ProtocolError;
 import exception.VersionError;
 import exception.SizeError;
 import exception.InternalError;
+import exception.TransmissionError;
 import protocolP2P.Payload;
 import protocolP2P.RequestResponseCode;
 import java.util.ArrayList;
 import java.lang.Byte;
 import java.net.DatagramPacket;
 import java.net.DatagramSocket;
+import java.net.InetAddress;
+import java.io.IOException;
+import java.net.UnknownHostException;
 
 /** Representation of datagram.
  * @author	Louis Royer
@@ -30,41 +34,61 @@ public class ProtocolP2PDatagram {
 		this.payload = payload;
 	}
 
-	/** Send datagram on socket
-	 * @param socket	DatagramSocket used to send datagram
+	/** Send datagram on socket (from client)
+	 * @param socket	DatagramSocket used to send datagram.
+	 * @param host	host to send datagram (null if this is a response)
+	 * @param port	port to send datagram (null if this is a response)
 	 * @throws	InternalError
+	 * @throws	UnknownHostException
+	 * @throws	IOException
 	 */
-	public void send(DatagramSocket socket) throws InternalError {
-		//TODO
+	public void send(DatagramSocket socket, String host, int port) throws InternalError, UnknownHostException, IOException {
+		InetAddress dst = InetAddress.getByName(host);
 		byte[] datagram = toDatagram();
 		// generate DatagramPacket
+		DatagramPacket datagramPacket = new DatagramPacket(datagram, datagram.length, dst, port);
 		// send it
+		socket.send(datagramPacket);
+	}
+
+	/** Send datagram on socket (from server, as a response)
+	 * @param socket	DatagramSocket used to send datagram.
+	 * @throws	InternalError
+	 * @throws	IOException
+	 */
+	public void send(DatagramSocket socket) throws InternalError, IOException {
+		byte[] datagram = toDatagram();
+		// generate DatagramPacket
+		DatagramPacket datagramPacket = new DatagramPacket(datagram, datagram.length);
+		socket.send(datagramPacket);
 	}
 
 	/** Receive datagram on socket
 	 * @param socket	DatagramSocket used to receive datagram
 	 * @return	payload of the datagram
+	 * @throws	TransmissionError
 	 * @throws	ProtocolError
 	 * @throws	VersionError
 	 * @throws	InternalError
 	 * @throws	SizeError
 	 */
-	public static Payload receive(DatagramSocket socket) throws ProtocolError, VersionError, InternalError, SizeError {
-		//TODO
+	public static Payload receive(DatagramSocket socket) throws TransmissionError, ProtocolError, VersionError, InternalError, SizeError {
 		// reception
-		byte[] datagram = new byte[5];
+		byte[] datagram = new byte[4096];
+		DatagramPacket reception = new DatagramPacket(datagram, datagram.length);
 		// contruction
 		ProtocolP2PDatagram p = new ProtocolP2PDatagram(datagram);
 		return p.getPayload();
 	}
 	/** Private constructor with datagram as byte[] parameter (typically used when receiving datagram).
 	 * @param datagram	the full datagram received
+	 * @throws	TransmissionError
 	 * @throws	ProtocolError
 	 * @throws	VersionError
 	 * @throws	InternalError
 	 * @throws	SizeError
 	 */
-	private ProtocolP2PDatagram(byte[] datagram) throws ProtocolError, VersionError, InternalError, SizeError {
+	private ProtocolP2PDatagram(byte[] datagram) throws TransmissionError, ProtocolError, VersionError, InternalError, SizeError {
 		// unwrap version
 		version = datagram[VERSION_POSITON];
 		checkProtocolVersion(); // this can throw VersionError
@@ -77,7 +101,7 @@ public class ProtocolP2PDatagram {
 				payload = (Payload) new FilePart(datagram);
 				break;
 			default:
-				payload = new Payload(datagram);
+				payload = new Payload(datagram); // this can throw TransmissionError
 				break;
 			}
 	}