implementing ServerListner.java

src/main/java/com/university/chat/Client/ServerListener.java

@@ -1,18 +1,27 @@
 package com.university.chat.Client;
 
+import com.university.chat.Common.ChatMessage;
+import com.university.chat.Common.FileMessage;
+
+import java.io.ObjectInputStream;
+
 public class ServerListener implements Runnable{
-    // TODO: store the ObjectInputStream from the user socket
+    private final ObjectInputStream in;
-    //          (this should be the same input stream the
+
-    //           chatClient created when connecting)
+    public ServerListener(ObjectInputStream in) {
+        this.in = in;
+    }
 
     @Override
     public void run() {
         try {
-            // TODO: In an infinite loop read objects from the server
+            while(true){
-            //   - if it's a ChatMessage  -> print "<sender>: <content>"
+                Object recived = in.readObject();
-            //   - if it's a FileMessage  -> print that a file was received
+                if(recived instanceof ChatMessage msg)
-            //                               (filename + sender), it's already
+                    System.out.println(msg.getSender() + "==> " + msg.getContent());
-            //                               saved to disk by the server.
+                else if(recived instanceof FileMessage fileMsg)
+                    System.out.println(fileMsg.getSender() + "sent ==> " +fileMsg.getFilename());
+            }
         } catch (Exception e){
             System.out.println("Disconnected from server");
         }

src/main/java/com/university/chat/Client/chatClient.java

@@ -1,29 +1,108 @@
 package com.university.chat.Client;
 
-public class chatClient {
+import com.university.chat.Common.ChatMessage;
-    public static void main() {
+import com.university.chat.Common.FileMessage;
-        // TODO: Connecting to the server
+import com.university.chat.Common.MessageType;
-        //  1. Create a socket and connect to the server
-        //  2. Create an ObjectOutputStream (out) and ObjectInputStream (in)
-        //      from the socket's streams — output FIRST, then input.
-        //  2. Get the username, and send a LOGIN ChatMessage with that username
-        //  3. Start a new Thread running a ServerListener(in) so incoming
-        //      messages are handled concurrently.
 
-        while (true){
+import java.io.IOException;
-            try {
+import java.io.ObjectInputStream;
-                // TODO: Program loop — read a line from the console and act on it:
+import java.io.ObjectOutputStream;
-                //   - "/msg <user> <text>"        -> build & send a PRIVATE_MESSAGE
+import java.net.Socket;
-                //   - "/users"                    -> build & send a USER_LIST request
+import java.nio.file.Files;
-                //   - "/sendfile <user> <path>"   -> read the file into a byte[]
+import java.nio.file.Path;
-                //                                     (you can use TransferProgress
+import java.nio.file.Paths;
-                //                                     to show progress)
+import java.util.Scanner;
-                //                                     and send it as a FileMessage
+
-                //   - anything else               -> send a PUBLIC_MESSAGE
+public class chatClient {
-                //   Remember to flush() the output stream after writeObject().
+
-            } catch (Exception e){
+    public static void main() {
-                System.out.println("command failed: " + e.getMessage());
+
+        final String SERVER_HOST = "localhost";
+        final int SERVER_PORT = 600;
+
+        Scanner input = new Scanner(System.in);
+
+        try {
+            Socket clientSocket = new Socket(SERVER_HOST, SERVER_PORT);
+
+            ObjectOutputStream output = new ObjectOutputStream(clientSocket.getOutputStream());
+            output.flush();
+            ObjectInputStream inputStream = new ObjectInputStream(clientSocket.getInputStream());
+
+            System.out.print("Username: ");
+            String username = input.nextLine();
+
+            output.writeObject(new ChatMessage(MessageType.LOGIN, username, null, null));
+            output.flush();
+
+            Thread serverThread = new Thread(new ServerListener(inputStream));
+            serverThread.start();
+
+            while (true) {
+                try {
+                    String command = input.nextLine();
+
+                    if (command.startsWith("/msg ")) {
+                        String[] args = command.substring(5).split(" ", 2);
+
+                        String recipient = args[0];
+                        String message = args.length > 1 ? args[1] : "";
+
+                        output.writeObject(new ChatMessage(
+                                MessageType.PRIVATE_MESSAGE,
+                                username,
+                                recipient,
+                                message));
+
+                        output.flush();
+                        continue;
+                    }
+
+                    if (command.equals("/users")) {
+                        output.writeObject(new ChatMessage(
+                                MessageType.USER_LIST,
+                                username,
+                                null,
+                                null));
+
+                        output.flush();
+                        continue;
+                    }
+
+                    if (command.startsWith("/sendfile ")) {
+                        String[] args = command.substring(10).split(" ", 2);
+
+                        String recipient = args[0];
+                        Path file = Paths.get(args[1]);
+
+                        byte[] fileData = Files.readAllBytes(file);
+                        String fileName = file.getFileName().toString();
+
+                        output.writeObject(new FileMessage(
+                                username,
+                                recipient,
+                                fileName,
+                                fileData));
+
+                        output.flush();
+                        continue;
+                    }
+
+                    output.writeObject(new ChatMessage(
+                            MessageType.PUBLIC_MESSAGE,
+                            username,
+                            null,
+                            command));
+
+                    output.flush();
+
+                } catch (Exception ex) {
+                    System.out.println("Command failed: " + ex.getMessage());
+                }
             }
+
+        } catch (IOException ex) {
+            System.out.println(ex.getMessage());
         }
     }
-}
+}

src/main/java/com/university/chat/Server/ChatServer.java

@@ -1,15 +1,28 @@
 package com.university.chat.Server;
 
+import java.io.IOException;
+import java.net.ServerSocket;
+import java.net.Socket;
+
 public class ChatServer {
-    // TODO: declare a single shared UserManager instance (static final)
+    public static final UserManager userManager = new UserManager();
-    //         This MUST be shared by all ClientSession threads so that
+    public static ServerSocket serverSocket;
-    //         broadcasting and private messaging work correctly.
 
     public static void main(String[] args) {
-        // TODO: Create a ServerSocket
+        try {
-
+            serverSocket = new ServerSocket(600);
-        // TODO: In an infinite loop:
+        } catch (IOException e){
-        //  accept an incoming client connection
+            throw new RuntimeException(e);
-        //  make a new thread running ClientSession for each user.
+        }
+        while(true){
+            try {
+                Socket socket = serverSocket.accept();
+                System.out.println("New user connected.");
+                ClientSession session = new ClientSession(socket, userManager);
+                new Thread(session).start();
+            } catch(IOException e){
+                System.err.println("Cannot connect: " + e.getMessage());
+            }
+        }
     }
 }

src/main/java/com/university/chat/Server/ClientSession.java

@@ -2,44 +2,80 @@ package com.university.chat.Server;
 
 import com.university.chat.Common.ChatMessage;
 import com.university.chat.Common.FileMessage;
+import com.university.chat.Common.MessageType;
 
 import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
 import java.net.Socket;
 import java.nio.file.Files;
 
 public class ClientSession implements Runnable {
 
     private String username;
+    private final UserManager userManager;
+    private final Socket socket;
+    private ObjectOutputStream out;
+    private ObjectInputStream in;
 
     public ClientSession(Socket socket, UserManager userManager) {
-        // TODO : Create an ObjectOutputStream from socket.getOutputStream()
+        this.socket = socket;
-        //         and an ObjectInputStream from socket.getInputStream().
+        this.userManager = userManager;
+        try {
+            out = new ObjectOutputStream(socket.getOutputStream());
+        } catch (IOException e) {
+            System.out.println(e.getMessage());
+        }
+
+        try {
+            in = new ObjectInputStream(socket.getInputStream());
+        } catch (IOException e) {
+            System.out.println(e.getMessage());
+        }
     }
 
     @Override
     public void run() {
         try {
+            System.out.println("Welcome");
+            boolean isLogedIn = false;
+            Object firstObject = in.readObject();
+            if(firstObject instanceof ChatMessage){
+                isLogedIn = ((ChatMessage)firstObject).getType() == MessageType.LOGIN;
+            }
 
-            // TODO: Welcome the user (login step)
+            if(!isLogedIn){
-            //  1. Read the first object sent by the client.
+                socket.close();
-            //  2. Check it's a ChatMessage with type LOGIN.
+                return;
-            //  3. Extract the username.
+            }
-            //  4. Try to register the user via userManager.addUser(...).
-            //  5. If the username is taken, send back LOGIN_FAILED and close the socket.
-            //  6. Otherwise, create the user's folders with FileManager.createUserFolders(...)
-            //      and send back LOGIN_SUCCESS.
 
-            // TODO: Main message loop
+            username = ((ChatMessage) firstObject).getSender();
-            //   In a loop, call in.readObject(), you can separate messages by their type:
+            if(userManager.addUser(username, this)){
-            //     - if it's a ChatMessage      -> call handleChatMessage(msg)
+                System.out.println(username + " user name added.");
-            //     - if it's a FileMessage      -> call handleFileMessage(fileMsg)
+                FileManager.createUserFolders(username);
-            //   Keep looping until the connection is closed (an exception will be thrown).
+                out.writeObject(MessageType.LOGIN_SUCCESS);
+                out.flush();
+            }
+            else{
+                System.out.println("try another username.");
+                out.writeObject(MessageType.LOGIN_FAILED);
+                out.flush();
+                socket.close();
+                return;
+            }
+
+            while(true){
+                Object obj = in.readObject();
+                if(obj instanceof ChatMessage)
+                    handleChatMessage((ChatMessage) obj);
+                else if(obj instanceof FileMessage)
+                    handleFileMessage((FileMessage) obj);
+            }
 
         } catch (Exception e) {
             System.out.println("Disconnected: " + username);
         } finally {
-            // TODO: Remove the user from UserManager so they no longer
+            userManager.removeUser(username);
-            //        receive broadcasts or appear in users list
         }
     }
 
@@ -47,13 +83,32 @@ public class ClientSession implements Runnable {
     private void handleChatMessage(ChatMessage msg) throws IOException {
         switch (msg.getType()) {
             case PUBLIC_MESSAGE -> {
-                // TODO: Broadcast this message to every connected client.
+                Iterable<ClientSession> users = userManager.getAllSessions();
+                for(ClientSession user : users){
+                    user.send(msg);
+                }
             }
             case PRIVATE_MESSAGE -> {
-                // TODO: Forward this message to the receiver user.
+                ClientSession receiver = userManager.getUser(msg.getReceiver());
+                if(receiver != null){
+                    receiver.send(msg);
+                }
+                else{
+                    send(new ChatMessage(
+                            MessageType.PRIVATE_MESSAGE,
+                            "server",
+                            username,
+                            "User doesn't exist: " + msg.getReceiver()
+                    ));
+                }
             }
             case USER_LIST -> {
-                // TODO: Reply to the requester with the list of online users.
+                send(new ChatMessage(
+                        MessageType.USER_LIST,
+                        "server",
+                        username,
+                        userManager.listUsers()
+                ));
             }
         }
     }
@@ -66,6 +121,11 @@ public class ClientSession implements Runnable {
         Files.write(sentPath, fileMsg.getData());
         Files.write(recvPath, fileMsg.getData());
 
-        // TODO: Forward the received file-message to the destination user.
+        ClientSession receiver = userManager.getUser(fileMsg.getReceiver());
+        receiver.send(fileMsg);
+    }
+    private synchronized void send(Object obj) throws IOException{
+        out.writeObject(obj);
+        out.flush();
     }
 }