Kick not working properly

disconnected clients can still send Messages to everyone

FIX:
Send Function in clientWindow.Java

private void send(String message, boolean text) {
      if (message.equals("")) return;
      if (text) {
         //removed this line cause we'll handle that in the server from now
         message = "/m/" + client.getID() + "/s/" + message + "/e/"; // I used s since it is the first letter of start of message but you can use anything you like
         txtMessage.setText("");
      }
      client.send(message.getBytes());
   }

Process function in Server.Java

private void process(DatagramPacket packet) {
      String string = new String(packet.getData());
      if (raw) System.out.println(string);
      if (string.startsWith("/c/")) {
         // UUID id = UUID.randomUUID();
         int id = UniqueIdentifier.getIdentifier();
         String name = string.split("/c/|/e/")[1];
         System.out.println(name + "(" + id + ") connected!");
         clients.add(new ServerClient(name, packet.getAddress(), packet.getPort(), id));
         String ID = "/c/" + id;
         send(ID, packet.getAddress(), packet.getPort());
      } else if (string.startsWith("/m/")) {
      // Part I changed --------------------------------------------------------
      int id;
      String s_id = string.split("/m/|/s/")[1];
      String name = null;
         try {
               id = Integer.parseInt(s_id);
            } catch (NumberFormatException e) {
               //wrong format
               return;
            }
         for (int i = 0; i < clients.size(); i++) {
               if (clients.get(i).getID() == id) {
                  name = clients.get(i).name;
                  break;
               }
            }
         if (name != null) sendToAll("/m/" + name + ": " string.split("/s/|/e/")[1] + "/e/");
      // -------------------------------------------------------------------------
      } else if (string.startsWith("/d/")) {
         String id = string.split("/d/|/e/")[1];
         disconnect(Integer.parseInt(id), true);
      } else if (string.startsWith("/i/")) {
         clientResponse.add(Integer.parseInt(string.split("/i/|/e/")[1]));
      } else {
         System.out.println(string);
      }
   }

[FuerstOpus]

Nice fix! I did something similar.

I did find myself doing that search over in different parts of the code, so I wrote getClient()

        private ServerClient getClient(int id){
            ServerClient c = null;
            for (int i = 0; i < clients.size(); i++) {
                if (clients.get(i).getID() == id) {
                    c = clients.get(i);
                    break;
                }
            }
            return c;
        }

It returns either the client object, or null if the object is not in the list.

Then I also made a version that takes a string:

        private ServerClient getClient(String name){
            ServerClient c = null;
            name = name.toLowerCase();
            int id = -1;
            try { // Create an Int id if possible
                id = Integer.parseInt(name);
            } catch (NumberFormatException e) {
            }
            // Search for either id or name match
            for (int i = 0; i < clients.size(); i++) {
                if (clients.get(i).getID() == id || clients.get(i).name.toLowerCase().equals(name)) {
                    c = clients.get(i);
                    break;
                }
            }
            return c;
        }

This is useful for the kick feature. It is case insensitive, and it will search on ID or name, so "/kick 12345" will find a user named "12345" or a user with the ID 12345 (whichever it finds first).