From 33a49821fc310fa9558f5df2e4c38f7e014bb1ce Mon Sep 17 00:00:00 2001 From: navid Date: Sun, 28 Jun 2026 20:53:23 +0330 Subject: [PATCH] Complete network chat system with file sharing --- .../chat/Client/ServerListener.java | 52 ++++++-- .../university/chat/Client/chatClient.java | 125 +++++++++++++++--- .../university/chat/Server/ChatServer.java | 25 +++- .../university/chat/Server/ClientSession.java | 121 ++++++++++++++--- 4 files changed, 266 insertions(+), 57 deletions(-) diff --git a/src/main/java/com/university/chat/Client/ServerListener.java b/src/main/java/com/university/chat/Client/ServerListener.java index b609d74..4250297 100644 --- a/src/main/java/com/university/chat/Client/ServerListener.java +++ b/src/main/java/com/university/chat/Client/ServerListener.java @@ -1,18 +1,54 @@ package com.university.chat.Client; +import com.university.chat.Common.ChatMessage; +import com.university.chat.Common.FileMessage; +import com.university.chat.Common.MessageType; + +import java.io.ObjectInputStream; + public class ServerListener implements Runnable{ - // TODO: store the ObjectInputStream from the user socket - // (this should be the same input stream the - // chatClient created when connecting) + private final ObjectInputStream in; + + public ServerListener(ObjectInputStream in) { + this.in = in; + } + @Override public void run() { try { - // TODO: In an infinite loop read objects from the server - // - if it's a ChatMessage -> print ": " - // - if it's a FileMessage -> print that a file was received - // (filename + sender), it's already - // saved to disk by the server. + while (true) { + Object obj = in.readObject(); + if (obj instanceof ChatMessage) { + ChatMessage msg = (ChatMessage) obj; + switch (msg.getType()) { + case LOGIN_SUCCESS: + System.out.println("\n[Server] " + msg.getContent()); + break; + case LOGIN_FAILED: + System.out.println("\n[Server] " + msg.getContent()); + System.exit(0); + break; + case PUBLIC_MESSAGE: + System.out.println("\n[" + msg.getSender() + "]: " + msg.getContent()); + break; + case PRIVATE_MESSAGE: + System.out.println("\n[Private from " + msg.getSender() + "]: " + msg.getContent()); + break; + case USER_LIST: + System.out.println("\n[Online users]: " + msg.getContent()); + break; + default: + System.out.println("\n[Server] " + msg.getContent()); + } + System.out.print("> "); + } else if (obj instanceof FileMessage) { + FileMessage fileMsg = (FileMessage) obj; + System.out.println("\n[File received] from " + fileMsg.getSender() + + ": " + fileMsg.getFilename() + " (saved to server_data)"); + System.out.print("> "); + } + } } catch (Exception e){ System.out.println("Disconnected from server"); } diff --git a/src/main/java/com/university/chat/Client/chatClient.java b/src/main/java/com/university/chat/Client/chatClient.java index dae0bad..2693648 100644 --- a/src/main/java/com/university/chat/Client/chatClient.java +++ b/src/main/java/com/university/chat/Client/chatClient.java @@ -1,29 +1,112 @@ package com.university.chat.Client; -public class chatClient { - public static void main() { - // TODO: Connecting to the server - // 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. +import com.university.chat.Common.ChatMessage; +import com.university.chat.Common.FileMessage; +import com.university.chat.Common.MessageType; - while (true){ - try { - // TODO: Program loop — read a line from the console and act on it: - // - "/msg " -> build & send a PRIVATE_MESSAGE - // - "/users" -> build & send a USER_LIST request - // - "/sendfile " -> read the file into a byte[] - // (you can use TransferProgress - // to show progress) - // and send it as a FileMessage - // - anything else -> send a PUBLIC_MESSAGE - // Remember to flush() the output stream after writeObject(). - } catch (Exception e){ +import java.io.*; +import java.net.Socket; +import java.nio.file.Files; +import java.nio.file.Path; +import java.nio.file.Paths; +import java.util.Scanner; + +public class chatClient { + + private static ObjectOutputStream out; + private static ObjectInputStream in; + private static String username; + + + public static void main(String[] args) { + try { + + Socket socket = new Socket("localhost", 12345); + + out = new ObjectOutputStream(socket.getOutputStream()); + in = new ObjectInputStream(socket.getInputStream()); + + Scanner scanner = new Scanner(System.in); + System.out.print("Enter your username: "); + username = scanner.nextLine().trim(); + + ChatMessage loginMsg = new ChatMessage(MessageType.LOGIN, username, null, ""); + out.writeObject(loginMsg); + out.flush(); + + + ServerListener listener = new ServerListener(in); + new Thread(listener).start(); + while (true){ + try { + System.out.print("> "); + String line = scanner.nextLine(); + if (line == null) break; + + if (line.equals("/exit") || line.equals("/quit")) { + System.out.println("Disconnecting..."); + break; + } + + if (line.startsWith("/msg ")) { + String[] parts = line.split(" ", 3); + if (parts.length < 3) { + System.out.println("Usage: /msg "); + continue; + } + String target = parts[1]; + String content = parts[2]; + ChatMessage privateMsg = new ChatMessage(MessageType.PRIVATE_MESSAGE, + username, target, content); + out.writeObject(privateMsg); + out.flush(); + } else if (line.equals("/users")) { + ChatMessage userListReq = new ChatMessage(MessageType.USER_LIST, + username, null, ""); + out.writeObject(userListReq); + out.flush(); + } else if (line.startsWith("/sendfile ")) { + String[] parts = line.split(" ", 3); + if (parts.length < 3) { + System.out.println("Usage: /sendfile "); + continue; + } + String target = parts[1]; + String filePath = parts[2]; + + Path path = Paths.get(filePath); + if (!Files.exists(path) || Files.isDirectory(path)) { + System.out.println("File does not exist or is a directory."); + continue; + } + + byte[] data = Files.readAllBytes(path); + String filename = path.getFileName().toString(); + + TransferProgress progress = new TransferProgress(data.length); + progress.update(data.length); + + FileMessage fileMsg = new FileMessage(username, target, filename, data); + out.writeObject(fileMsg); + out.flush(); + System.out.println("File sent to " + target); + } else { + ChatMessage publicMsg = new ChatMessage(MessageType.PUBLIC_MESSAGE, + username, null, line); + out.writeObject(publicMsg); + out.flush(); + } + }catch (IOException e) { + System.out.println("Connection lost. Exiting..."); + break; + } catch (Exception e){ System.out.println("command failed: " + e.getMessage()); } } + socket.close(); + scanner.close(); + } catch (Exception e) { + System.out.println("Connection error: " + e.getMessage()); + } } } diff --git a/src/main/java/com/university/chat/Server/ChatServer.java b/src/main/java/com/university/chat/Server/ChatServer.java index b2a35ae..ba6e688 100644 --- a/src/main/java/com/university/chat/Server/ChatServer.java +++ b/src/main/java/com/university/chat/Server/ChatServer.java @@ -1,15 +1,26 @@ package com.university.chat.Server; +import java.net.ServerSocket; +import java.net.Socket; + public class ChatServer { - // TODO: declare a single shared UserManager instance (static final) - // This MUST be shared by all ClientSession threads so that - // broadcasting and private messaging work correctly. + private static final UserManager userManager = new UserManager(); public static void main(String[] args) { - // TODO: Create a ServerSocket + final int PORT = 12345; + + try (ServerSocket serverSocket = new ServerSocket(PORT)) { + System.out.println("Chat Server started on port " + PORT); + + while (true) { + Socket clientSocket = serverSocket.accept(); + System.out.println("New client connected: " + clientSocket.getInetAddress()); + ClientSession session = new ClientSession(clientSocket, userManager); + new Thread(session).start(); + } + } catch (Exception e) { + System.err.println("Server error: " + e.getMessage()); + } - // TODO: In an infinite loop: - // accept an incoming client connection - // make a new thread running ClientSession for each user. } } diff --git a/src/main/java/com/university/chat/Server/ClientSession.java b/src/main/java/com/university/chat/Server/ClientSession.java index f09d64a..384788f 100644 --- a/src/main/java/com/university/chat/Server/ClientSession.java +++ b/src/main/java/com/university/chat/Server/ClientSession.java @@ -2,44 +2,94 @@ 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 final Socket socket; + private final UserManager userManager; + private ObjectOutputStream out; + private ObjectInputStream in; private String username; public ClientSession(Socket socket, UserManager userManager) { - // TODO : Create an ObjectOutputStream from socket.getOutputStream() - // and an ObjectInputStream from socket.getInputStream(). + this.socket = socket; + this.userManager = userManager; + try { + out = new ObjectOutputStream(socket.getOutputStream()); + in = new ObjectInputStream(socket.getInputStream()); + } catch (IOException e) { + System.err.println("Error initializing streams: " + e.getMessage()); + try { + socket.close(); + } catch (IOException ignored) {} + } } @Override public void run() { try { + if (out == null || in == null) { + return; + } - // TODO: Welcome the user (login step) - // 1. Read the first object sent by the client. - // 2. Check it's a ChatMessage with type LOGIN. - // 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. + Object first = in.readObject(); + if (!(first instanceof ChatMessage)) { + socket.close(); + return; + } - // TODO: Main message loop - // In a loop, call in.readObject(), you can separate messages by their type: - // - if it's a ChatMessage -> call handleChatMessage(msg) - // - if it's a FileMessage -> call handleFileMessage(fileMsg) - // Keep looping until the connection is closed (an exception will be thrown). + ChatMessage loginMsg = (ChatMessage) first; + if (loginMsg.getType() != MessageType.LOGIN) { + socket.close(); + return; + } + + String requestedUsername = loginMsg.getSender(); + + if (!userManager.addUser(requestedUsername, this)) { + ChatMessage failure = new ChatMessage(MessageType.LOGIN_FAILED, "Server", null, + "Username '" + requestedUsername + "' is already taken."); + out.writeObject(failure); + out.flush(); + socket.close(); + return; + } + + this.username = requestedUsername; + FileManager.createUserFolders(username); + + ChatMessage success = new ChatMessage(MessageType.LOGIN_SUCCESS, "Server", null, + "Welcome " + username + "!"); + out.writeObject(success); + out.flush(); + + System.out.println("User logged in: " + username); + + 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 - // receive broadcasts or appear in users list + if (username != null) { + userManager.removeUser(username); + } + try { + socket.close(); + } catch (IOException ignored) {} } } @@ -47,14 +97,34 @@ 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. + for (ClientSession session : userManager.getAllSessions()) { + session.out.writeObject(msg); + session.out.flush(); + } } case PRIVATE_MESSAGE -> { - // TODO: Forward this message to the receiver user. + String receiver = msg.getReceiver(); + ClientSession target = userManager.getUser(receiver); + if (target != null) { + target.out.writeObject(msg); + target.out.flush(); + } else { + ChatMessage error = new ChatMessage(MessageType.PRIVATE_MESSAGE, "Server", + msg.getSender(), "User '" + receiver + "' is not online."); + out.writeObject(error); + out.flush(); + } } case USER_LIST -> { - // TODO: Reply to the requester with the list of online users. + String list = userManager.listUsers(); + ChatMessage reply = new ChatMessage(MessageType.USER_LIST, "Server", + msg.getSender(), list); + out.writeObject(reply); + out.flush(); } + default -> { + } + } } @@ -66,6 +136,15 @@ 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 target = userManager.getUser(fileMsg.getReceiver()); + if (target != null) { + target.out.writeObject(fileMsg); + target.out.flush(); + }else { + ChatMessage error = new ChatMessage(MessageType.PRIVATE_MESSAGE, "Server", + fileMsg.getSender(), "User '" + fileMsg.getReceiver() + "' is not online. File saved on server."); + out.writeObject(error); + out.flush(); + } } } \ No newline at end of file -- 2.54.0