Another complete overhaul of client-server communication:

-Added broadcastAnnouncement message to ClientHandler
-Bugfix: "Connection lost" at startup
-Added LOGIN$username to protocol

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/Client.java

@@ -20,16 +20,24 @@ public class Client {
   private Socket socket;
   private BufferedReader in;
   private BufferedWriter out;
-  public String userName;
   public ClientPinger clientPinger;
 
-  public Client(Socket socket, String userName) {
+  public Client(Socket socket) {
     try {
       this.socket = socket;
       this.out = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
       this.in = new BufferedReader((new InputStreamReader((socket.getInputStream()))));
-      this.userName = userName;
+
-      sendMsgToServer(getUsername());     //todo: dont just send username directly pls
+      //sending the initial name to server.
+      String systemName;
+      try {
+        systemName = System.getProperty("user.name");
+      } catch (Exception e) {
+        systemName = "Unknown User";
+      }
+      if (systemName == null) systemName = "Unknown User";
+      sendMsgToServer("LOGON$" + systemName);
+
       clientPinger = new ClientPinger(this, this.socket);
     } catch (IOException e) {
       e.printStackTrace();
@@ -53,9 +61,7 @@ public class Client {
               sendMsgToServer(formattedMSG);
             }
             Thread.sleep(20);
-          } catch (IOException e) {
+          } catch (IOException | InterruptedException e) {
-            e.printStackTrace();
-          } catch (InterruptedException e) {
             e.printStackTrace();
           }
           //LOGGER.debug("just checked next line");
@@ -67,12 +73,10 @@ public class Client {
 
 
   /**
-   * Starts a thread which listens for incoming messages
+   * Starts a thread which listens for incoming chat messages / other messages that the user
+   * has to see
    */
   public void chatListener() {
-        /*TODO: what type of decoding has to be done
-          TODO how shall input be logged?
-         */
     new Thread(new Runnable() {
       @Override
       public void run() {
@@ -144,19 +148,18 @@ public class Client {
     String hostname;
     int port = 42069;               //can be set via argument later if needed.
     if (args.length < 1) {
-      System.out.println("Enter the host's IP address (or type localhost)");
+      System.out.println("Enter the host's IP address (or type l for localhost)");
       hostname = sc.next();
+      if (hostname == "l") {
+        hostname = "localhost";
+      }
     } else {
       hostname = args[0];
     }
-    String systemName = System.getProperty("user.name");
-    System.out.println("Choose a nickname (Suggestion: " + systemName
-        + "): "); //Suggests a name based on System username
-    String username = sc.next();
     Socket socket;
     try {
       socket = new Socket(hostname, 42069);
-      Client client = new Client(socket, username);
+      Client client = new Client(socket);
       client.chatListener();
       Thread cP = new Thread(client.clientPinger);
       cP.start();
@@ -169,10 +172,6 @@ public class Client {
 
   }
 
-  public String getUsername() {
-    return userName;
-  }
-
   public Socket getSocket() {
     return socket;
   }

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/client/JClientProtocolParser.java

@@ -16,11 +16,13 @@ public class JClientProtocolParser {
    * @param c   this Client(required so this method can access the Client's methods)
    */
   public static void parse(String msg, Client c) {
+    //LOGGER.debug("got message: " + msg + ".");
     String header = "";             //"header" is the first 5 characters, i.e. the protocol part
     try {
       header = msg.substring(0, 5);
     } catch (IndexOutOfBoundsException e) {
       System.out.println("Received unknown command");
+      e.printStackTrace();
     }
     switch (header) {
       case "SPING":
@@ -40,7 +42,7 @@ public class JClientProtocolParser {
         break;
       case "QUITC":
         c.closeEverything();
-        System.out.println("bye!");
+        break;
       default:
         System.out.println("Received unknown command");
     }

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/helpers/ClientPinger.java

@@ -36,7 +36,7 @@ public class ClientPinger implements Runnable {
   @Override
   public void run() {
     try {
-      Thread.sleep(2000);
+      Thread.sleep(20000);
       while (socket.isConnected() && !socket.isClosed()) {
         gotPingBack = false;
         client.sendMsgToServer("CPING");

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/helpers/Protocol.txt

@@ -1,6 +1,7 @@
-Client commands:
+Client to server commands:
 
 Implemented:
+ * LOGON$name         Log on, with the name set to whatever follow $.
  * CHATA$message      Send chat message to all
  * QUITS              request to quit server/ leave server. The server should then remove the
                       relevant ClientHandler and close the sockets, but before doing so, it sends
@@ -20,7 +21,7 @@ Future / planned:
  * VOTEH              humans voting who is the ghost
  * LISTP              list players/clients in session with the Server
 
-Server Commands:
+Server to client Commands:
 
 Implemented:
  * SPING              Ping from server to client

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/server/ClientHandler.java

@@ -33,19 +33,21 @@ public class ClientHandler implements Runnable {
     try {
       this.socket = socket;
       this.out = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
-      this.in = new BufferedReader((new InputStreamReader((socket.getInputStream()))));
+      this.in = new BufferedReader(new InputStreamReader((socket.getInputStream())));
-      this.clientUserName = in.readLine();
+      this.clientUserName = "Mysterious Passenger";    //todo: duplicate handling for this
-      // duplicate handling: if username already taken, assign random name to client
+      /*
+      // todo: duplicate handling more elegantly
       if (AllClientNames.allNames("").contains(clientUserName)) {
         clientUserName = NameGenerator.randomName(clientUserName);
       }
       // add username to list of all client names for future duplicate checking
       AllClientNames.allNames(clientUserName);
+
+       */
       connectedClients.add(this);
       serverPinger = new ServerPinger(out, socket);
       Thread sP = new Thread(serverPinger);
       sP.start();
-      broadcastChatMessage("SERVER: " + clientUserName + " has joined the Server");
     } catch (IOException e) {
       e.printStackTrace();
     }
@@ -109,23 +111,52 @@ public class ClientHandler implements Runnable {
    * @param newName The desired new name to replace the old one with.
    */
   public void changeUsername(String newName) {
-    if (AllClientNames.allNames("").contains(newName)) {
+    if (AllClientNames.allNames("").contains(newName)) {    //todo: more elegant solution
       newName = NameGenerator.randomName(newName);
     }
     String h = this.clientUserName; //just a friendly little helper
     this.clientUserName = newName;
     AllClientNames.allNames(newName);
-    broadcastChatMessage(h + " have changed their nickname to " + clientUserName);
+    broadcastAnnouncement(h + " has changed their nickname to " + clientUserName);
   }
 
   /**
-   * Broadcasts a Message to all active clients in the form "Username: msg"
+   * Sets the client's username on login, if the username is already taken, a similar
+   * option is chosen. Functionally, the only difference between this method and changeUsername
+   * is that it doesn't print out the name change.
    *
-   * @param msg the Message to be broadcasted
+   * @param name The desired name.
+   */
+  public void setUsernameOnLogin(String name) {
+    //todo: duplicate checking
+    this.clientUserName = name;
+    broadcastAnnouncement(  clientUserName + " has joined the Server");
+    //todo: add this name to namelist
+  }
+
+  /**
+   * Broadcasts a Message to all active clients in the form "Username: @msg"
+   *
+   * @param msg the Message to be broadcast
    */
   public void broadcastChatMessage(String msg) {
     for (ClientHandler client : connectedClients) {
-      client.sendMsgToClient("CHATM$" + clientUserName + ": \"" + msg + "\"");
+      client.sendMsgToClient("CHATM$" + clientUserName + ": " + msg);
+    }
+  }
+
+  /**
+   * Broadcasts a non-chat Message to all active clients. This can be used for server
+   * messages / announcements rather than chat messages. The message will be printed to the user ex-
+   * actly as it is given to this method. Unlike broadcastChatMessage, it will also be printed onto
+   * the server console.
+   *
+   * @param msg the Message to be broadcast
+   */
+  public void broadcastAnnouncement(String msg) {
+    System.out.println(msg);
+    for (ClientHandler client : connectedClients) {
+      client.sendMsgToClient("CHATM$" + msg);
     }
   }
 

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/server/JServerProtocolParser.java

@@ -21,6 +21,7 @@ public class JServerProtocolParser {
    * @param h   this ClientHandler (required so this method can access the ClientHandler's methods)
    */
   public static void parse(String msg, ClientHandler h) {
+    //LOGGER.debug("got message: " + msg + ".");
     String header = "";             //"header" is the first 5 characters, i.e. the protocol part
         try {
       header = msg.substring(0, 5);
@@ -32,6 +33,14 @@ public class JServerProtocolParser {
         //sends chat message to all connected clients
         h.broadcastChatMessage(msg.substring(6));
         break;
+      case "LOGON":
+        //sets name to whatever follows LOGON$
+        try {
+          h.setUsernameOnLogin(msg.substring(6));
+        } catch (Exception e) {
+          h.setUsernameOnLogin("A Mysterious Passenger");
+        }
+        break;
       case "NAMEC":
         //changes name to whatever follows NAMEC$. If the new name is already in use, it will append
         //random numbers to the name.
@@ -47,6 +56,7 @@ public class JServerProtocolParser {
         break;
       case "QUITS":
         //safely disconnects the user
+        h.broadcastAnnouncement(h.getClientUserName() + " has left the server.");
         h.disconnectClient();
         break;
       default:

src/main/java/ch/unibas/dmi/dbis/cs108/multiplayer/server/Server.java

@@ -34,15 +34,6 @@ public class Server {
         Thread th = new Thread(nextClient);
         connectedClients.add(nextClient);
         th.start();
-        // close socket + remove client if client is disconnected
-        /* TODO: Modify or remove this disconnection handling - right now, it is not functioning
-            (when disconnecting there are "broken pipe" exceptions on client side and "stream closed"
-            exceptions on the server side).
-         */
-        if (nextClient.getSocket().getInputStream().read() == -1) {
-          System.out.println("client disconnected. closing socket");
-          socket.close();
-        }
       }
     } catch (IOException e) {
       e.printStackTrace();