Changed listener to an interface.

README.md

@@ -2,28 +2,29 @@
 
 A fork of [kryonet](https://github.com/EsotericSoftware/kryonet/), a Java library that provides a clean and simple API for efficient network communication.
 
-This fork was specifically made for [ProjectGG]() and adds only a few small improvements.
+This fork was specifically made for [ProjectGG](https://github.com/Meidimax99/ProjektGG) but also adds the most demanded features on kryonet's issue tracker.
 
 ### Key Changes
 * A TypeListener for easier message handling (see the example below)
-* Fixes for the Android 5 and iOS crashes
+* Listener is now a interface ([#39](https://github.com/EsotericSoftware/kryonet/issues/39))
+* Uses kryo 4.0.0 ([#77](https://github.com/EsotericSoftware/kryonet/issues/77))
+* Fixes for the Android 5 and iOS crashes ([#106](https://github.com/EsotericSoftware/kryonet/issues/106))
 
 ### Usage of the changes
 
 This code adds a listener to handle receiving objects:
 
 ```java
-        TypeListener typeListener = new TypeListener();
+TypeListener typeListener = new TypeListener();
 
-		typeListener.addTypeHandler(SomeRequest.class,
-				(con, msg) -> {
-					System.out.println(msg.getSomeData());
-				});
-		typeListener.addTypeHandler(SomeOtherRequest.class,
-				(con, msg) -> {
-					con.sendTCP(new SomeResponse());
-				});
+typeListener.addTypeHandler(SomeRequest.class,
+   (con, msg) -> {
+      System.out.println(msg.getSomeData());
+   });
+typeListener.addTypeHandler(SomeOtherRequest.class,
+   (con, msg) -> {
+      con.sendTCP(new SomeResponse());
+});
 
-		server.addListener(typeListener);
-    });
+server.addListener(typeListener);
 ```

src/main/java/com/esotericsoftware/kryonet/Listener.java

@@ -30,23 +30,21 @@
 /**
  * Used to be notified about connection events.
  */
-public class Listener {
+public interface Listener {
 	/**
 	 * Called when the remote end has been connected. This will be invoked
 	 * before any objects are received by {@link #received(Connection, Object)}.
 	 * This will be invoked on the same thread as {@link Client#update(int)} and
 	 * {@link Server#update(int)}. This method should not block for long periods
 	 * as other network activity will not be processed until it returns.
 	 */
-	public void connected(Connection connection) {
-	}
+	public void connected(Connection connection);
 
 	/**
 	 * Called when the remote end is no longer connected. There is no guarantee
 	 * as to what thread will invoke this method.
 	 */
-	public void disconnected(Connection connection) {
-	}
+	public void disconnected(Connection connection);
 
 	/**
 	 * Called when an object has been received from the remote end of the
@@ -55,14 +53,36 @@ public void disconnected(Connection connection) {
 	 * should not block for long periods as other network activity will not be
 	 * processed until it returns.
 	 */
-	public void received(Connection connection, Object object) {
-	}
+	public void received(Connection connection, Object object);
 
 	/**
 	 * Called when the connection is below the
 	 * {@link Connection#setIdleThreshold(float) idle threshold}.
 	 */
-	public void idle(Connection connection) {
+	public void idle(Connection connection);
+
+	/**
+	 * Wraps the listener interface and implements
+	 * {@link Listener#idle(Connection)} and
+	 * {@link Listener#received(Connection, Object)}.
+	 *
+	 */
+	public abstract class ConnectionListener implements Listener {
+
+		@Override
+		public abstract void disconnected(Connection arg0);
+
+		@Override
+		public abstract void connected(Connection arg0);
+
+		@Override
+		public void received(Connection connection, Object object) {
+		}
+
+		@Override
+		public void idle(Connection connection) {
+		}
+
 	}
 
 	/**
@@ -72,7 +92,7 @@ public void idle(Connection connection) {
 	 * Add a handler for a specific type via
 	 * {@link #addHandler(Class, BiConsumer)}.
 	 */
-	public class TypeListener extends Listener {
+	static public class TypeListener implements Listener {
 
 		/**
 		 * All type listeners.
@@ -102,14 +122,26 @@ public <T> void addTypeHandler(Class<T> clazz,
 			listeners.put(clazz, listener);
 		}
 
+		@Override
+		public void connected(Connection connection) {
+		}
+
+		@Override
+		public void disconnected(Connection connection) {
+		}
+
+		@Override
+		public void idle(Connection connection) {
+		}
+
 	}
 
 	/**
 	 * Wraps a listener and queues notifications as {@link Runnable runnables}.
 	 * This allows the runnables to be processed on a different thread,
 	 * preventing the connection's update thread from being blocked.
 	 */
-	static public abstract class QueuedListener extends Listener {
+	static public abstract class QueuedListener implements Listener {
 		final Listener listener;
 
 		public QueuedListener(Listener listener) {

src/main/java/com/esotericsoftware/kryonet/rmi/ObjectSpace.java

@@ -126,6 +126,14 @@ public void run() {
 		public void disconnected(Connection connection) {
 			removeConnection(connection);
 		}
+
+		@Override
+		public void connected(Connection connection) {
+		}
+
+		@Override
+		public void idle(Connection connection) {
+		}
 	};
 
 	/**
@@ -450,6 +458,14 @@ public void received(Connection connection, Object object) {
 				public void disconnected(Connection connection) {
 					close();
 				}
+
+				@Override
+				public void connected(Connection connection) {
+				}
+
+				@Override
+				public void idle(Connection connection) {
+				}
 			};
 			connection.addListener(responseListener);
 		}

src/main/java/com/esotericsoftware/kryonet/util/TcpIdleSender.java

@@ -22,7 +22,7 @@
 import com.esotericsoftware.kryonet.Connection;
 import com.esotericsoftware.kryonet.Listener;
 
-abstract public class TcpIdleSender extends Listener {
+abstract public class TcpIdleSender implements Listener {
 	boolean started;
 
 	public void idle(Connection connection) {