两个安卓设备用TCP互相连接例子

以下是两个 Android 设备之间使用 TCP 协议互相连接的示例代码：

在发送端的设备上：

public class ClientThread implements Runnable {
    private Socket socket;
    private String serverIp;
    private int serverPort;

    public ClientThread(String serverIp, int serverPort) {
        this.serverIp = serverIp;
        this.serverPort = serverPort;
    }

    @Override
    public void run() {
        try {
            InetAddress serverAddr = InetAddress.getByName(serverIp);
            socket = new Socket(serverAddr, serverPort);

            // 发送数据
            OutputStream outputStream = socket.getOutputStream();
            String message = "Hello server!";
            outputStream.write(message.getBytes());

            // 接收数据
            InputStream inputStream = socket.getInputStream();
            byte[] buffer = new byte[1024];
            int length = inputStream.read(buffer);
            String receivedMessage = new String(buffer, 0, length);
            Log.d("ClientThread", "Received message: " + receivedMessage);

            socket.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

// 启动客户端线程
new Thread(new ClientThread("192.168.0.100", 12345)).start();

在接收端的设备上：

public class ServerThread implements Runnable {
    private ServerSocket serverSocket;
    private int serverPort;

    public ServerThread(int serverPort) {
        this.serverPort = serverPort;
    }

    @Override
    public void run() {
        try {
            serverSocket = new ServerSocket(serverPort);

            while (true) {
                Socket socket = serverSocket.accept();

                // 接收数据
                InputStream inputStream = socket.getInputStream();
                byte[] buffer = new byte[1024];
                int length = inputStream.read(buffer);
                String receivedMessage = new String(buffer, 0, length);
                Log.d("ServerThread", "Received message: " + receivedMessage);

                // 发送数据
                OutputStream outputStream = socket.getOutputStream();
                String message = "Hello client!";
                outputStream.write(message.getBytes());

                socket.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

// 启动服务器线程
new Thread(new ServerThread(12345)).start();

以上代码中，客户端线程向指定的服务器 IP 和端口发送数据，服务器线程监听指定的端口并接受客户端的连接请求，接收客户端发送的数据并发送响应数据。请将 `192.168.0.100` 替换为发送端设备的 IP 地址。