java tcp实现聊天室

Java TCP 实现聊天室需要通过网络套接字实现，具体步骤如下：

1. 创建服务器端和客户端的 Socket 连接。服务器端需要绑定一个端口号来监听客户端的连接请求。

2. 服务器端需要开启一个线程来接收客户端的连接请求，并创建一个对应的 Socket 连接。客户端需要连接服务器端的 Socket 连接。

3. 服务器端将客户端的 Socket 连接保存在一个集合中，以便后续广播消息给所有客户端。

4. 客户端和服务器端都需要开启一个线程来处理接收和发送消息。

5. 客户端发送消息时，需要将消息发送给服务器端，服务器端再将消息广播给所有客户端。

下面是一个简单的 Java TCP 实现聊天室的示例代码：

服务器端代码：

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;

public class Server {

    private ServerSocket serverSocket;
    private List<Socket> clients = new ArrayList<>();

    public Server(int port) {
        try {
            serverSocket = new ServerSocket(port);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void start() {
        System.out.println("Server started!");
        while (true) {
            try {
                Socket client = serverSocket.accept();
                clients.add(client);
                new Thread(new ServerHandler(client)).start();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    private class ServerHandler implements Runnable {

        private Socket client;

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

        @Override
        public void run() {
            try {
                InputStream is = client.getInputStream();
                byte[] buffer = new byte[1024];
                int len;
                while ((len = is.read(buffer)) != -1) {
                    String message = new String(buffer, 0, len);
                    System.out.println("Received from client: " + message);
                    broadcast(message);
                }
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                try {
                    client.close();
                    clients.remove(client);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    private void broadcast(String message) {
        for (Socket client : clients) {
            try {
                OutputStream os = client.getOutputStream();
                os.write(message.getBytes());
                os.flush();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    public static void main(String[] args) {
        Server server = new Server(8888);
        server.start();
    }
}

客户端代码：

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.Socket;
import java.util.Scanner;

public class Client {

    private Socket socket;

    public void connect(String host, int port) {
        try {
            socket = new Socket(host, port);
            new Thread(new ClientHandler(socket)).start();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void send(String message) {
        try {
            OutputStream os = socket.getOutputStream();
            os.write(message.getBytes());
            os.flush();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private class ClientHandler implements Runnable {

        private Socket socket;

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

        @Override
        public void run() {
            try {
                InputStream is = socket.getInputStream();
                byte[] buffer = new byte[1024];
                int len;
                while ((len = is.read(buffer)) != -1) {
                    String message = new String(buffer, 0, len);
                    System.out.println("Received from server: " + message);
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    public static void main(String[] args) {
        Client client = new Client();
        client.connect("localhost", 8888);
        Scanner scanner = new Scanner(System.in);
        while (true) {
            String message = scanner.nextLine();
            client.send(message);
        }
    }
}

这个简单的聊天室支持多个客户端连接，客户端发送的消息会被广播给所有客户端。