Java开发带有私聊功能的简易聊天室代码

以下是一个简易聊天室的 Java 代码，它带有私聊功能。它使用了 Java 的 Socket 编程和多线程技术来实现。请注意，这只是一个基本的实现，需要进一步扩展和改进。

Server.java:

import java.io.*;
import java.net.*;
import java.util.*;

public class Server {
    private static ArrayList<Socket> clients = new ArrayList<Socket>();
    private static ArrayList<String> usernames = new ArrayList<String>();

    public static void main(String[] args) throws Exception {
        ServerSocket server = new ServerSocket(1234);

        while (true) {
            System.out.println("Waiting for clients to connect...");
            Socket client = server.accept();
            System.out.println("Client connected from " + client.getInetAddress().getHostAddress());
            clients.add(client);
            new Thread(new ClientHandler(client)).start();
        }
    }

    public static void broadcast(String message, Socket sender) throws Exception {
        for (Socket client : clients) {
            if (client != sender) {
                PrintWriter writer = new PrintWriter(client.getOutputStream(), true);
                writer.println(message);
            }
        }
    }

    public static void sendPrivateMessage(String message, String recipient, Socket sender) throws Exception {
        int recipientIndex = usernames.indexOf(recipient);
        if (recipientIndex != -1) {
            Socket recipientSocket = clients.get(recipientIndex);
            PrintWriter writer = new PrintWriter(recipientSocket.getOutputStream(), true);
            writer.println("Private message from " + sender.getInetAddress().getHostAddress() + ": " + message);
        } else {
            PrintWriter writer = new PrintWriter(sender.getOutputStream(), true);
            writer.println("Recipient not found.");
        }
    }

    private static class ClientHandler implements Runnable {
        private Socket client;

        public ClientHandler(Socket client) {
            this.client = client;
        }

        public void run() {
            try {
                BufferedReader reader = new BufferedReader(new InputStreamReader(client.getInputStream()));
                PrintWriter writer = new PrintWriter(client.getOutputStream(), true);

                writer.println("Enter your username:");
                String username = reader.readLine();
                usernames.add(username);
                broadcast(username + " has joined the chat.", client);

                String message;
                while ((message = reader.readLine()) != null) {
                    if (message.startsWith("@")) {
                        int spaceIndex = message.indexOf(" ");
                        if (spaceIndex != -1) {
                            String recipient = message.substring(1, spaceIndex);
                            String privateMessage = message.substring(spaceIndex + 1);
                            sendPrivateMessage(privateMessage, recipient, client);
                        }
                    } else {
                        broadcast(username + ": " + message, client);
                    }
                }

                usernames.remove(username);
                clients.remove(client);
                broadcast(username + " has left the chat.", client);

                client.close();
            } catch (Exception e) {
                System.out.println("Error handling client: " + e);
            }
        }
    }
}

Client.java:

import java.io.*;
import java.net.*;
import java.util.*;

public class Client {
    public static void main(String[] args) throws Exception {
        Scanner scanner = new Scanner(System.in);

        System.out.print("Enter server IP address: ");
        String serverAddress = scanner.nextLine();

        Socket socket = new Socket(serverAddress, 1234);
        BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
        PrintWriter writer = new PrintWriter(socket.getOutputStream(), true);

        System.out.print("Enter your username: ");
        String username = scanner.nextLine();
        writer.println(username);

        new Thread(new ServerHandler(socket)).start();

        String message;
        while ((message = scanner.nextLine()) != null) {
            writer.println(message);
        }

        socket.close();
    }

    private static class ServerHandler implements Runnable {
        private Socket socket;

        public ServerHandler(Socket socket) {
            this.socket = socket;
        }

        public void run() {
            try {
                BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));

                String message;
                while ((message = reader.readLine()) != null) {
                    System.out.println(message);
                }
            } catch (Exception e) {
                System.out.println("Error receiving message: " + e);
            }
        }
    }
}

这个聊天室允许用户输入他们的用户名，然后发送消息到聊天室中的所有人或私人消息到一个特定的用户。私人消息应该以“@username message”的形式发送。例如，如果您想向名为“john”的用户发送私人消息“hello”，您可以输入“@john hello”。