Add default user data folder for mac

src/clientP2P/ClientP2P.java

@@ -23,7 +23,11 @@ public class ClientP2P {
 					d += ".";
 				}
 			}
-		} else {
+		} else if (os.equals("Mac")||os.equals("Mac OS X") {
+			/* Apple MacOS X User Data Directory
+			 * https://developer.apple.com/library/archive/qa/qa1170/_index.html */
+			d = System.getProperty("user.home") + "/Library/";
+		}  else {
 			d = ".";
 		}
 		d += "/P2P_JAVA_PROJECT_CLIENT/";

src/serverP2P/ServerP2P.java

@@ -11,7 +11,8 @@ public class ServerP2P {
 		/* Follow XDG Base Directory Specification
 		 * https://specifications.freedesktop.org/basedir-spec/basedir-spec-latest.html
 		 */
-		if (System.getProperty("os.name").equals("Linux")) {
+		String os = System.getProperty("os.name");
+		if (os.equals("Linux")) {
 			d = System.getenv().get("XDG_DATA_HOME");
 			if (d == null || d.equals("")) {
 				d = System.getenv().get("HOME");
@@ -21,6 +22,10 @@ public class ServerP2P {
 					d += ".";
 				}
 			}
+		} else if (os.equals("Mac")||os.equals("Mac OS X") {
+			/* Apple MacOS X User Data Directory
+			 * https://developer.apple.com/library/archive/qa/qa1170/_index.html */
+			d = System.getProperty("user.home") + "/Library/";
 		} else {
 			d = ".";
 		}