added client/server ping + remove inactive connections from server

Mage.Server/src/main/java/mage/server/ChatManager.java

@@ -70,7 +70,7 @@ public class ChatManager {
 		chatSessions.get(chatId).broadcast(userName, message, color);
 	}
 
-	void removeSession(UUID sessionId) {
+	public void removeSession(UUID sessionId) {
 		for (ChatSession chat: chatSessions.values()) {
 			chat.kill(sessionId);
 		}

Mage.Server/src/main/java/mage/server/ServerImpl.java

@@ -45,6 +45,7 @@ import mage.game.tournament.TournamentOptions;
 import mage.interfaces.Server;
 import mage.interfaces.ServerState;
 import mage.interfaces.callback.ClientCallback;
+import mage.server.Session;
 import mage.server.game.DeckValidatorFactory;
 import mage.server.draft.DraftManager;
 import mage.server.game.GameFactory;
@@ -105,6 +106,16 @@ public class ServerImpl extends RemoteServer implements Server {
 		SessionManager.getInstance().getSession(sessionId).ack(message);
 	}
 
+	@Override
+	public boolean ping(UUID sessionId) {
+		Session session = SessionManager.getInstance().getSession(sessionId);
+		if (session != null) {
+			session.ping();
+			return true;
+		}
+		return false;
+	}
+
 	@Override
 	public UUID registerClient(String userName, UUID clientId, MageVersion version) throws MageException, RemoteException {
 
@@ -241,8 +252,8 @@ public class ServerImpl extends RemoteServer implements Server {
 						Session session = SessionManager.getInstance().getSession(sessionId);
 						if (session != null) {
 							session.kill();
+							logger.info("Client deregistered ...");
 						}
-						logger.info("Client deregistered ...");
 					}
 				}
 			);

Mage.Server/src/main/java/mage/server/Session.java

@@ -28,6 +28,7 @@
 
 package mage.server;
 
+import java.util.Date;
 import java.util.logging.Level;
 import java.util.UUID;
 import mage.cards.decks.Deck;
@@ -50,6 +51,7 @@ public class Session {
 	private String username;
 	private int messageId = 0;
 	private String ackMessage;
+	private long lastPing;
 	private final CallbackServerSession callback = new CallbackServerSession();
 
 	public Session(String userName, UUID clientId) {
@@ -137,4 +139,12 @@ public class Session {
 		return username;
 	}
 
+	public void ping() {
+		this.lastPing = System.currentTimeMillis();
+	}
+
+	public boolean stillAlive() {
+		return (System.currentTimeMillis() - lastPing) < 60000;
+	}
+
 }

Mage.Server/src/main/java/mage/server/SessionManager.java

@@ -30,6 +30,9 @@ package mage.server;
 
 import java.util.UUID;
 import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.concurrent.TimeUnit;
 import mage.interfaces.MageException;
 import org.apache.log4j.Logger;
 
@@ -41,15 +44,20 @@ public class SessionManager {
 
 	private final static Logger logger = Logger.getLogger(SessionManager.class);
 	private final static SessionManager INSTANCE = new SessionManager();
+	private static ScheduledExecutorService sessionExecutor;
 
 	public static SessionManager getInstance() {
 		return INSTANCE;
 	}
 
+	protected SessionManager() {
+		sessionExecutor = Executors.newScheduledThreadPool(1);
+		sessionExecutor.scheduleWithFixedDelay(new SessionChecker(), 30, 10, TimeUnit.SECONDS);
+	}
+
 	private ConcurrentHashMap<UUID, Session> sessions = new ConcurrentHashMap<UUID, Session>();
 
 	public Session getSession(UUID sessionId) {
-		if (sessions == null || sessionId == null) return null;
 		return sessions.get(sessionId);
 	}
 
@@ -74,5 +82,24 @@ public class SessionManager {
 	public void removeSession(UUID sessionId) {
 		sessions.remove(sessionId);
 	}
-	
+
+	public void checkSessions() {
+		for (Session session: sessions.values()) {
+			if (!session.stillAlive()) {
+				logger.info("Client for user " + session.getUsername() + " timed out - releasing resources");
+				session.kill();
+				sessions.remove(session.getId());
+			}
+		}
+	}
+
+	class SessionChecker implements Runnable {
+
+		@Override
+		public void run() {
+			checkSessions();
+		}
+
+	}
 }
+