added the feature that a client can host a server

- added a class BattleshipServer (a client host a local server) and ReceivedMessage
- edited the NetworkDialog, that a client has a checkbox to select to host a server
-

Projekte/battleship/client/src/main/java/pp/battleship/client/BattleshipServer.java

@@ -0,0 +1,245 @@
+////////////////////////////////////////
+// Programming project code
+// UniBw M, 2022, 2023, 2024
+// www.unibw.de/inf2
+// (c) Mark Minas (mark.minas@unibw.de)
+////////////////////////////////////////
+
+package pp.battleship.client;
+
+import com.jme3.network.ConnectionListener;
+import com.jme3.network.HostedConnection;
+import com.jme3.network.Message;
+import com.jme3.network.MessageListener;
+import com.jme3.network.Network;
+import com.jme3.network.Server;
+import com.jme3.network.serializing.Serializer;
+import pp.battleship.BattleshipConfig;
+import pp.battleship.game.server.Player;
+import pp.battleship.game.server.ServerGameLogic;
+import pp.battleship.game.server.ServerSender;
+import pp.battleship.message.client.ClientMessage;
+import pp.battleship.message.client.MapMessage;
+import pp.battleship.message.client.ShootMessage;
+import pp.battleship.message.server.EffectMessage;
+import pp.battleship.message.server.GameDetails;
+import pp.battleship.message.server.ServerMessage;
+import pp.battleship.message.server.StartBattleMessage;
+import pp.battleship.model.Battleship;
+import pp.battleship.model.IntPoint;
+import pp.battleship.model.Shot;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.lang.System.Logger;
+import java.lang.System.Logger.Level;
+import java.util.concurrent.BlockingQueue;
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.logging.LogManager;
+
+/**
+ * Server implementing the visitor pattern as MessageReceiver for ClientMessages
+ */
+public class BattleshipServer implements MessageListener<HostedConnection>, ConnectionListener, ServerSender {
+    /**
+     * Logger for the BattleshipServer class.
+     */
+    private static final Logger LOGGER = System.getLogger(BattleshipServer.class.getName());
+
+    /**
+     * Configuration file for the server.
+     */
+    private static final File CONFIG_FILE = new File("server.properties");
+
+    /**
+     * Port number for the server.
+     */
+    private final int PORT_NUMBER;
+
+    /**
+     * Configuration settings for the Battleship server.
+     */
+    private final BattleshipConfig config = new BattleshipConfig();
+
+    /**
+     * The server instance.
+     */
+    private Server myServer;
+
+    /**
+     * Game logic for the server.
+     */
+    private final ServerGameLogic logic;
+
+    /**
+     * Queue for pending messages to be processed by the server.
+     */
+    private final BlockingQueue<ReceivedMessage> pendingMessages = new LinkedBlockingQueue<>();
+
+    static {
+        // Configure logging
+        LogManager manager = LogManager.getLogManager();
+        try {
+            manager.readConfiguration(new FileInputStream("logging.properties"));
+            LOGGER.log(Level.INFO, "Successfully read logging properties"); //NON-NLS
+        } catch (IOException e) {
+            LOGGER.log(Level.INFO, e.getMessage());
+        }
+    }
+
+    /**
+     * Creates the server.
+     */
+    public BattleshipServer(int PORT_NUMBER) {
+        config.readFromIfExists(CONFIG_FILE);
+        this.PORT_NUMBER = PORT_NUMBER;
+        LOGGER.log(Level.INFO, "Configuration: {0}", config); //NON-NLS
+        logic = new ServerGameLogic(this, config);
+    }
+
+    /**
+     * Starts the server and processes incoming messages indefinitely.
+     */
+    public void run() {
+        startServer();
+        while (true)
+            processNextMessage();
+    }
+
+    /**
+     * Starts the server and initializes necessary components.
+     * This method sets up the server, registers serializable classes,
+     * starts the server, and registers listeners for incoming connections and messages.
+     * If the server fails to start, it logs an error and exits the application.
+     */
+    private void startServer() {
+        try {
+            LOGGER.log(Level.INFO, "Starting server..."); //NON-NLS
+            myServer = Network.createServer(PORT_NUMBER);
+            initializeSerializables();
+            myServer.start();
+            registerListeners();
+            LOGGER.log(Level.INFO, "Server started: {0}", myServer.isRunning()); //NON-NLS
+        } catch (IOException e) {
+            LOGGER.log(Level.ERROR, "Couldn't start server: {0}", e.getMessage()); //NON-NLS
+            exit(1);
+        }
+    }
+
+    /**
+     * Processes the next message in the queue.
+     * This method blocks until a message is available, then processes it using the server logic.
+     * If interrupted while waiting, it logs the interruption and re-interrupts the thread.
+     */
+    private void processNextMessage() {
+        try {
+            pendingMessages.take().process(logic);
+        } catch (InterruptedException ex) {
+            LOGGER.log(Level.INFO, "Interrupted while waiting for messages"); //NON-NLS
+            Thread.currentThread().interrupt();
+        }
+    }
+
+    /**
+     * Registers the serializable classes used by the server.
+     * This method ensures that the necessary classes are registered with the serializer
+     * so that they can be correctly transmitted over the network.
+     */
+    private void initializeSerializables() {
+        Serializer.registerClass(GameDetails.class);
+        Serializer.registerClass(StartBattleMessage.class);
+        Serializer.registerClass(MapMessage.class);
+        Serializer.registerClass(ShootMessage.class);
+        Serializer.registerClass(EffectMessage.class);
+        Serializer.registerClass(Battleship.class);
+        Serializer.registerClass(IntPoint.class);
+        Serializer.registerClass(Shot.class);
+    }
+
+    /**
+     * Registers listeners for incoming connections and messages.
+     * This method adds message listeners for `MapMessage` and `ShootMessage` classes,
+     * and a connection listener for handling connection events.
+     */
+    private void registerListeners() {
+        myServer.addMessageListener(this, MapMessage.class);
+        myServer.addMessageListener(this, ShootMessage.class);
+        myServer.addConnectionListener(this);
+    }
+
+    /**
+     * Handles the reception of messages from clients.
+     *
+     * @param source  the connection from which the message was received
+     * @param message the message received from the client
+     */
+    @Override
+    public void messageReceived(HostedConnection source, Message message) {
+        LOGGER.log(Level.INFO, "message received from {0}: {1}", source.getId(), message); //NON-NLS
+        if (message instanceof ClientMessage clientMessage)
+            pendingMessages.add(new ReceivedMessage(clientMessage, source.getId()));
+    }
+
+    /**
+     * Called when a new connection is added to the server.
+     *
+     * @param server           the server to which the connection was added
+     * @param hostedConnection the connection that was added
+     */
+    @Override
+    public void connectionAdded(Server server, HostedConnection hostedConnection) {
+        LOGGER.log(Level.INFO, "new connection {0}", hostedConnection); //NON-NLS
+        logic.addPlayer(hostedConnection.getId());
+    }
+
+    /**
+     * Called when a connection is removed from the server.
+     *
+     * @param server           the server from which the connection was removed
+     * @param hostedConnection the connection that was removed
+     */
+    @Override
+    public void connectionRemoved(Server server, HostedConnection hostedConnection) {
+        LOGGER.log(Level.INFO, "connection closed: {0}", hostedConnection); //NON-NLS
+        final Player player = logic.getPlayerById(hostedConnection.getId());
+        if (player == null)
+            LOGGER.log(Level.INFO, "closed connection does not belong to an active player"); //NON-NLS
+        else { //NON-NLS
+            LOGGER.log(Level.INFO, "closed connection belongs to {0}", player); //NON-NLS
+            exit(0);
+        }
+    }
+
+    /**
+     * Exits the application with the specified exit value.
+     * Closes all client connections and logs the close request.
+     *
+     * @param exitValue the exit value to be used when exiting the application
+     */
+    private void exit(int exitValue) { //NON-NLS
+        LOGGER.log(Level.INFO, "close request"); //NON-NLS
+        if (myServer != null)
+            for (HostedConnection client : myServer.getConnections()) //NON-NLS
+                if (client != null) client.close("Game over"); //NON-NLS
+        System.exit(exitValue);
+    }
+
+    /**
+     * Send the specified message to the specified connection.
+     *
+     * @param id      the connection id
+     * @param message the message
+     */
+    public void send(int id, ServerMessage message) {
+        if (myServer == null || !myServer.isRunning()) {
+            LOGGER.log(Level.ERROR, "no server running when trying to send {0}", message); //NON-NLS
+            return;
+        }
+        final HostedConnection connection = myServer.getConnection(id);
+        if (connection != null)
+            connection.send(message);
+        else
+            LOGGER.log(Level.ERROR, "there is no connection with id={0}", id); //NON-NLS
+    }
+}

Projekte/battleship/client/src/main/java/pp/battleship/client/NetworkDialog.java

@@ -7,6 +7,7 @@
 
 package pp.battleship.client;
 
+import com.simsilica.lemur.Checkbox;
 import com.simsilica.lemur.Container;
 import com.simsilica.lemur.Label;
 import com.simsilica.lemur.TextField;
@@ -30,6 +31,7 @@ class NetworkDialog extends SimpleDialog {
     private static final Logger LOGGER = System.getLogger(NetworkDialog.class.getName());
     private static final String LOCALHOST = "localhost"; //NON-NLS
     private static final String DEFAULT_PORT = "1234"; //NON-NLS
+    private static final int START_SERVER_DELAY = 2000;
     private final NetworkSupport network;
     private final TextField host = new TextField(LOCALHOST);
     private final TextField port = new TextField(DEFAULT_PORT);
@@ -37,6 +39,7 @@ class NetworkDialog extends SimpleDialog {
     private int portNumber;
     private Future<Object> connectionFuture;
     private Dialog progressDialog;
+    private boolean hostServer = false;
 
     /**
      * Constructs a new NetworkDialog.
@@ -50,21 +53,26 @@ class NetworkDialog extends SimpleDialog {
         host.setPreferredWidth(400f);
         port.setSingleLine(true);
 
+        Checkbox hostCheckbox = new Checkbox(lookup("host.own-server"));
+        hostCheckbox.setChecked(false);
+        hostCheckbox.addClickCommands(s -> hostServer = !hostServer);
+
         final BattleshipApp app = network.getApp();
         final Container input = new Container(new SpringGridLayout());
         input.addChild(new Label(lookup("host.name") + ":  "));
         input.addChild(host, 1);
         input.addChild(new Label(lookup("port.number") + ":  "));
         input.addChild(port, 1);
+        input.addChild(hostCheckbox);
 
         DialogBuilder.simple(app.getDialogManager())
-                     .setTitle(lookup("server.dialog"))
+                .setTitle(lookup("server.dialog"))
-                     .setExtension(d -> d.addChild(input))
+                .setExtension(d -> d.addChild(input))
-                     .setOkButton(lookup("button.connect"), d -> connect())
+                .setOkButton(lookup("button.connect"), d -> connectHostServer())
-                     .setNoButton(lookup("button.cancel"), app::closeApp)
+                .setNoButton(lookup("button.cancel"), app::closeApp)
-                     .setOkClose(false)
+                .setOkClose(false)
-                     .setNoClose(false)
+                .setNoClose(false)
-                     .build(this);
+                .build(this);
     }
 
     /**
@@ -78,19 +86,54 @@ private void connect() {
             portNumber = Integer.parseInt(port.getText());
             openProgressDialog();
             connectionFuture = network.getApp().getExecutor().submit(this::initNetwork);
-        }
+        } catch (NumberFormatException e) {
-        catch (NumberFormatException e) {
             network.getApp().errorDialog(lookup("port.must.be.integer"));
         }
     }
 
+    /**
+     * Connects to the host server. If the `hostServer` flag is set, it starts the server
+     * before attempting to connect. If the server fails to start, logs an error.
+     */
+    private void connectHostServer() {
+        if (hostServer) {
+            startServer();
+            try {
+                Thread.sleep(START_SERVER_DELAY);
+            } catch (Exception e) {
+                LOGGER.log(Level.ERROR, "Server start failed", e); //NON-NLS
+            }
+            connect();
+        } else {
+            connect();
+        }
+    }
+
+    /**
+     * Starts the game server in a new thread.
+     * Logs an error if the server fails to start.
+     */
+    private void startServer() {
+        LOGGER.log(Level.INFO, "start server"); //NON-NLS
+        new Thread(() -> {
+            try {
+                LOGGER.log(Level.INFO, "Starting server..."); //NON-NLS
+                BattleshipServer server = new BattleshipServer(Integer.parseInt(port.getText()));
+                LOGGER.log(Level.INFO, "Server started"); //NON-NLS
+                server.run();
+            } catch (Exception e) {
+                LOGGER.log(Level.ERROR, "Server start failed", e); //NON-NLS
+            }
+        }).start();
+    }
+
     /**
      * Creates a dialog indicating that the connection is in progress.
      */
     private void openProgressDialog() {
         progressDialog = DialogBuilder.simple(network.getApp().getDialogManager())
-                                      .setText(lookup("label.connecting"))
+                .setText(lookup("label.connecting"))
-                                      .build();
+                .build();
         progressDialog.open();
     }
 
@@ -103,8 +146,7 @@ private Object initNetwork() {
         try {
             network.initNetwork(hostname, portNumber);
             return null;
-        }
+        } catch (Exception e) {
-        catch (Exception e) {
             throw new RuntimeException(e);
         }
     }
@@ -119,11 +161,9 @@ public void update(float delta) {
             try {
                 connectionFuture.get();
                 success();
-            }
+            } catch (ExecutionException e) {
-            catch (ExecutionException e) {
                 failure(e.getCause());
-            }
+            } catch (InterruptedException e) {
-            catch (InterruptedException e) {
                 LOGGER.log(Level.WARNING, "Interrupted!", e); //NON-NLS
                 Thread.currentThread().interrupt();
             }

Projekte/battleship/client/src/main/java/pp/battleship/client/ReceivedMessages.java

@@ -0,0 +1,28 @@
+////////////////////////////////////////
+// Programming project code
+// UniBw M, 2022, 2023, 2024
+// www.unibw.de/inf2
+// (c) Mark Minas (mark.minas@unibw.de)
+////////////////////////////////////////
+
+package pp.battleship.client;
+
+import pp.battleship.message.client.ClientInterpreter;
+import pp.battleship.message.client.ClientMessage;
+
+/**
+ * Represents a received message from a client.
+ *
+ * @param message the client message
+ * @param from    the ID of the sender
+ */
+record ReceivedMessage(ClientMessage message, int from) {
+    /**
+     * Processes the received message using the specified interpreter.
+     *
+     * @param interpreter the client interpreter
+     */
+    void process(ClientInterpreter interpreter) {
+        message.accept(interpreter, from);
+    }
+}

Projekte/battleship/model/src/main/resources/battleship.properties

@@ -24,6 +24,7 @@ button.connect=Connect
 button.cancel=Cancel
 server.dialog=Server
 host.name=Host
+host.own-server=Host own server
 port.number=Port
 wait.its.not.your.turn=Wait, it's not your turn!!
 menu.quit=Quit game

Projekte/battleship/model/src/main/resources/battleship_de.properties

@@ -25,6 +25,7 @@ button.cancel=Abbruch
 server.dialog=Server
 host.name=Host
 port.number=Port
+host.own-server=Server hosten
 wait.its.not.your.turn=Warte, Du bist nicht dran!!
 menu.quit=Spiel beenden
 menu.return-to-game=Zurück zum Spiel