java import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.net.ServerSocket; import java.net.Socket;

public class NetworkTransfer {

public static void main {
    try {
        // 监听本地的9999端口
        ServerSocket serverSocket = new ServerSocket;
        System.out.println;
        // 等待客户端连接
        Socket clientSocket = serverSocket.accept;
        System.out.println);
        // 获取输入输出流
        InputStream in = clientSocket.getInputStream;
        OutputStream out = clientSocket.getOutputStream;
        // 从输入流中读取数据
        byte buffer = new byte; // 创建一个缓冲区
        int n; // 用于存储读取的字节数
        while ) != -1) { // 读取数据直到流收尾
            System.out.println); // 输出读取到的数据
            // 向输出流中写入数据
            out.write;
            out.flush; // 确保数据被发送
        }
        // 关闭连接
        in.close;
        out.close;
        clientSocket.close;
        serverSocket.close;
    } catch  {
        e.printStackTrace;
    }
}

}