Detailed explanation of examples based on java TCP network communication

package TCP;

import java.io.*;

import java.net.*;

import javax.swing.*;

 public class Server {

     //服务器端的输入流

    static  BufferedReader br;

     //服务器端的输出流

    static  PrintStream ps;

     //服务器相关的界面组件

    static  JTextArea text;   

            JFrame frame;

    public Server(){

        //服务器端的界面的实例化

        JFrame frame=new JFrame("服务器端");

        text=new JTextArea();

        JScrollPane scroll =new JScrollPane(text);

        frame.add(scroll);

        frame.setVisible(true);

        frame.setSize(300,400);

        //这里设置服务器端的文本框是不可编辑的

        text.setEditable(false);

    }

    public static void main(String[] args) throws Exception{      

        new Server();    //生成服务器界面

        //通过服务器端构造函数  ServerSocket(port) 实例化一个服务器端口

        ServerSocket server=new ServerSocket(2000);

        text.append("监听2000端口"+"\n");

        //实例化一个接受服务器数据的对象

        Socket client=server.accept();

        br =new BufferedReader(new InputStreamReader(client.getInputStream()));

        ps =new PrintStream(client.getOutputStream());       

        String msg;

        //如果输入流不为空,将接受到的信息打印到相应的文本框中并反馈回收到的信息

        while ((msg =br.readLine())!=null) 

        {

            text.append("服务器端收到："+msg+"\n");

            ps.println(msg);

            if(msg.equals("quit"))

            {  

                text.append("客户端“2000”已退出！"+"\n");

                text.append("服务器程序将退出！");               

                break;

            }

        }

        ps.close();

        br.close();

        client.close();

    }

}

package TCP;

import java.awt.*;

import java.awt.event.*;

import java.io.*;

import javax.swing.*;

import java.net.*;

public class Client implements ActionListener{

   //这里有两个图形界面，一个是连接的frame,另一个和服务器通信的界面frame1   

    private  JFrame frame;

    private  JLabel adress;

    private  JLabel port;

             JTextField adresstext;

             JTextField porttext;

             JButton connect;

    private JFrame frame1;

    private JLabel shuru;

    private JPanel panel1;

    private JPanel panel2;

    private JLabel jieshou;

            JButton send;

    static JTextArea shurukuang;

    static TextArea jieshoukuang;

    //从服务端接受的数据流

    static BufferedReader br1;

    //从客户端输出的数据流

    static PrintStream ps;

    //从通信界面中的输入框接受的数据流

    static BufferedReader br2;

    static Socket client;

    //将输入框字符串转换为字符串流所需的字符串的输入流

    static ByteArrayInputStream stringInputStream ;

   public Client() {

       //连接界面的实例化

        frame=new JFrame();

        adress=new JLabel("IP 地址");

        port =new JLabel("端口号");

        adresstext=new JTextField("127.0.0.1",10);

        porttext=new JTextField("2000",10);

        connect=new JButton("连接");

            //连接界面的布局          

        frame.setLayout(new FlowLayout());

        frame.add(adress);

        frame.add(adresstext);

        frame.add(port);  

        frame.add(porttext);

        frame.add(connect);

        frame.setVisible(true);

        frame.setSize(200,150);          

        connect.addActionListener(this);

          //通信界面的实例化

        frame1=new JFrame();

        shuru=new JLabel("请输入");

          shurukuang=new JTextArea("请输入····",5,40); 

          panel1=new JPanel();

          panel1.add(shuru);

          panel1.add(shurukuang);

          panel1.setLayout(new FlowLayout());

          send=new JButton("发送");

          panel2=new JPanel();

          jieshou=new JLabel("已接受");

         jieshoukuang=new TextArea(8,60);    

          jieshoukuang.setEditable(false);

          panel2.add(jieshou);

          panel2.add(jieshoukuang);

          panel2.setLayout(new FlowLayout());       

          frame1.setLayout(new FlowLayout());

              //通信界面都的布局

          frame1.add(BorderLayout.NORTH,panel1);

          frame1.add(send);

          frame1.add(BorderLayout.SOUTH,panel2);

             //连接时通信界面是处于看不到的

          frame1.setVisible(false);

          frame1.setSize(500,350);

          send.addActionListener(this); 

            }

         //两个界面当中都有相应的按钮时间，为相应的时间添加动作

      public  void  actionPerformed(ActionEvent e) {

         if(e.getSource()==connect){   

          try {

                  //当触发连接按钮时，实例化一个客户端

                client=new Socket("127.0.0.1",2000);   

                  //隐藏连接界面，显示通信界面

                frame.setVisible(false);

                frame1.setVisible(true);

                jieshoukuang.append("已经连接上服务器！"+"\n");           

           } catch (IOException e1){

                 System.out.println("链接失败！");

                e1.printStackTrace();

             }

         }

         //通信界面中的发送按钮相应的时间处理

        if(e.getSource()==send){

              //将输入框中的字符串转换为字符串流

             stringInputStream = new ByteArrayInputStream((shurukuang.getText()).getBytes());

             br2 =new BufferedReader(new InputStreamReader(stringInputStream));

             String msg;

             try{

              while((msg=br2.readLine())!=null){   

                  ps.println(msg);   //将输入框中的内容发送给服务器端       

                  jieshoukuang.append("向服务器发送："+msg+"\n");

                  jieshoukuang.append("客户端接受相应:"+br1.readLine()+"\n");

                  if(msg.equals("quit"))

                     {

                        jieshoukuang.append("客户端将退出!");

                        br1.close();

                        ps.close();

                        client.close();

                        frame1.setVisible(false);

                        break;

                           }                     

                      }   

             }catch(IOException e2){

                 System.out.println("读输入框数据出错！");                 

              }

             shurukuang.setText("");

          }

      } 

      public static void main(String[] args) throws IOException{

           new Client();  //实例化连接界面

           client=new Socket("127.0.0.1",2000);            

           //从服务端接受的数据 

           br1=new BufferedReader(new InputStreamReader(client.getInputStream()));

            //从客户端输出的数据

           ps =new PrintStream(client.getOutputStream());         

              }

        }