服务器端

import java.net.*;    import java.io.*;        public class TCPServer {        public TCPServer() throws Exception{    ServerSocket ss = new ServerSocket(6666);          while (true) {                Socket s = ss.accept();                new ServerThread(s).start();                        }   }      public static void main(String[] args) throws Exception {           new TCPServer();          }              protected class ServerThread extends Thread{        Socket s;       public ServerThread(Socket s1){        s = s1;       }       public void run(){         System.out.println("a client connect!");          try{                  DataInputStream dis = new DataInputStream(s.getInputStream());//服务器通过输入管道接收数据流                    String str;              while((str = dis.readUTF()).length() > 0){                      System.err.println(str);//输出读入的数据                }          }        catch(Exception ex){         ex.printStackTrace();        }         }      }  }

import java.awt.EventQueue;    import javax.swing.JFrame;  import javax.swing.JPanel;  import javax.swing.border.EmptyBorder;  import javax.swing.JButton;  import java.awt.event.ActionListener;  import java.awt.event.ActionEvent;  import java.io.DataOutputStream;  import java.io.OutputStream;  import java.net.Socket;  import javax.swing.JTextField;    public class TCPClientFrame extends JFrame {   Socket s;   DataOutputStream dos;   private JPanel contentPane;   private JTextField textField;   private JButton button;     /**    * Launch the application.    */   public static void main(String[] args) {    EventQueue.invokeLater(new Runnable() {     public void run() {      try {       TCPClientFrame frame = new TCPClientFrame();       frame.setVisible(true);      } catch (Exception e) {       e.printStackTrace();      }     }    });   }     /**    * Create the frame.    */   public TCPClientFrame() {    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);    setBounds(100, 100, 450, 300);    contentPane = new JPanel();    contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));    setContentPane(contentPane);    contentPane.setLayout(null);        JButton btnNewButton = new JButton("连接");    btnNewButton.addActionListener(new ActionListener() {     public void actionPerformed(ActionEvent e) {      try{       s = new Socket("127.0.0.1", 6666);               OutputStream os = s.getOutputStream();  //得到输出管道               dos = new DataOutputStream(os);//创建数据传输流        }      catch(Exception ex){       ex.printStackTrace();      }     }    });    btnNewButton.setBounds(10, 10, 93, 23);    contentPane.add(btnNewButton);        JButton btnNewButton_1 = new JButton("发消息");    btnNewButton_1.addActionListener(new ActionListener() {     public void actionPerformed(ActionEvent e) {      try{        dos.writeUTF(textField.getText());//客户端传输数据             dos.flush();        }      catch(Exception ex){       ex.printStackTrace();      }     }    });    btnNewButton_1.setBounds(141, 10, 93, 23);    contentPane.add(btnNewButton_1);        textField = new JTextField();    textField.setBounds(10, 56, 66, 21);    contentPane.add(textField);    textField.setColumns(10);        button = new JButton("自动发消息");    button.addActionListener(new ActionListener() {     public void actionPerformed(ActionEvent e) {      try{       while(true){         dos.writeUTF("======自动发的消息");//客户端传输数据              dos.flush();         }             }      catch(Exception ex){       ex.printStackTrace();      }     }    });    button.setBounds(314, 10, 93, 23);    contentPane.add(button);   }  }