【Java】Socket套接字C/S结构简单练习

 

 

 

服务端Server代码：

package Server;
import java.io.*;
import java.net.*;

public class TServer {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        ServerSocket serverSocket = null;
        ServerThread serverThread ;
        final int portNum = 39839;  //使用11520发现一直是在创建serverSocket时失败
        Socket clientSocket = null;
        
        try {
            serverSocket = new ServerSocket(portNum);
        } catch (IOException e) {
            //e.printStackTrace();
            System.out.println("启动服务端时，发生错误....");
        }
        System.out.println("服务端已启动....\n等待客户端的连接......");
        
        while(true){
            try {
                    clientSocket = serverSocket.accept();
                    if (clientSocket.isConnected()) 
                        System.out.println("客户端IP【"+clientSocket.getInetAddress().getHostAddress()+"】连接进入...");
            } catch (IOException e) {
                //e.printStackTrace();
                System.out.println("等待客户端呼入时，发生错误....");
            }
            if (clientSocket.isConnected()) {  //增加对socket连接的判断，避免因为客户端的在中途断开连接引起的线程错误
                    serverThread = new ServerThread(clientSocket);
                    serverThread.start();
            }else {
                    continue;
            }
        } 
            
    }

}



class ServerThread extends Thread{
    Socket socket;    
    String s = null;
    DataOutputStream outs = null;
    DataInputStream ins = null;
    
    ServerThread(Socket sct){
        socket = sct;
        try {
            ins = new DataInputStream(sct.getInputStream());
            outs = new DataOutputStream(sct.getOutputStream());
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    
    @SuppressWarnings("deprecation")
    public void run(){
        while(true){
            try {
                if (socket.isConnected())
                    s = ins.readUTF();
                else 
                    //this.destroy(); // 异常断开的连接直接清理掉。。这个处理方式不行，会导致整个线程死掉（待完善，如果意外中断的socket再次连接时，能够自动续接）
                    break;
            } catch (IOException e) {
                // TODO Auto-generated catch block
                System.out.println("客户端【"+socket.getInetAddress().getHostAddress()+"】异常中断...");
                break;
            }
            
            try {
                if (s.equals("结束")){
                    outs.writeUTF(s);
                    socket.close();    //关闭当前客户端的连接
                    System.out.println("客户端IP【"+socket.getInetAddress().getHostAddress()+"】正常退出连接！");
                    this.stop();     //当前线程结束
                }else{
                    System.out.println("客户端IP【"+socket.getInetAddress().getHostAddress()+"】发来消息："+s);
                    outs.writeUTF("" + socket.getInetAddress().getHostName() + "，你对我说了【"+ s + "】");
                }
            } catch (IOException e) {
                // TODO Auto-generated catch block
                System.out.println("向客户端发送信息失败...");
            }
        }
    }
}

 

客户端Client代码：

package Client;
import java.awt.event.*;
import java.awt.*;
import javax.swing.*;
import javax.xml.crypto.dsig.keyinfo.KeyValue;

import java.io.*;
import java.net.*;
import java.util.concurrent.TimeoutException;

public class JavaClientSocketMain {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        TClient tcFrame = new TClient();
        tcFrame.setVisible(true);
    }

}


class TClient extends JFrame implements ActionListener, Runnable,KeyListener {
    JButton btSend ;    JButton btRelink ;
    JTextField textF ;        JTextArea textA;
    JScrollPane scrollPane;
    SocketAddress socketAddr;
    Socket socket ;        Thread thread ;  
    //TimeoutThread loseConnectionThread;
    DataInputStream ins;    DataOutputStream outs;
    final int portNum = 39839;
    final String serverIPAddress = "192.168.1.124";
    
    TClient(){
        setBackground(new Color(120,153,137));
        setLayout(new BorderLayout());
        btSend = new JButton("发送信息");
        btRelink = new JButton("重新连接");
        textF = new JTextField(20); //限长文本框
        textA = new JTextArea(20,30); //限长限宽文本区
        scrollPane = new JScrollPane(textA);
        textA.setText("正在请求连接服务端......");
        setSize(450,350);
        setLocationRelativeTo(null); //窗体于屏幕居中显示
        JPanel p = new JPanel();
        p.add(textF);    p.add(btSend); p.add(btRelink);
        this.add(scrollPane, "Center");    this.add(p,  "South");
        btSend.addActionListener(this);
        btRelink.addActionListener(this);
        textF.addKeyListener(this);
        
        //窗口退出按钮事件
        this.addWindowListener(new WindowAdapter(){
            public void windowClosing(WindowEvent e){
                try {
                    socket.close();
                    thread.stop();
                } catch (IOException e1) {}
                System.exit(0);
            }
        });
        
        linkToServer(serverIPAddress , portNum);  //构造器，连接到服务器
    }
    
    
    
    @Override
    public void run() {
        // 线程运行过程
        String s = null;
        while(true) {
            try {
                s = ins.readUTF(); //读取服务端放入流中的信息
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
                return ;
            }
            if (s.equals("结束")){  //当服务器放入流中的信息有“结束”两字时，关闭socket连接
                try {
                    socket.close();
                    System.exit(0);
                    //break;
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                    return ;
                }
            }
            else
                textA.append(s + "\n");
        }
        
    }
    
    //发送消息
    public void sendMessage(){
        if (socket.isConnected()){
            String s = textF.getText();
            if (s != null){
                try {
                    outs.writeUTF(s);
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
            else {
                try {
                    outs.writeUTF("请服务端发送信息！");
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }else {
            textA.append("\n...未连接....");
        }
        textF.setText("");
    }
    
    // 连接到指定的服务端
    public boolean linkToServer(String ipAddr, int pNum){
        try {
            socketAddr = new InetSocketAddress(ipAddr,pNum);
            socket = new Socket() ; 
            socket.connect(socketAddr,1000);    // 192.168.1.124作为服务端 端口4321，等待1秒钟，如果1秒钟之后还没有连接上，则抛出异常
            
            if(socket.isConnected()){
                ins = new DataInputStream(socket.getInputStream());
                outs = new DataOutputStream(socket.getOutputStream());
                textA.setText("已连接到"+socket.getInetAddress().getHostAddress()+"\n");
            }
            
        } catch (UnknownHostException e) {
            //e.printStackTrace();
            textA.setText("找不到服务端啦...\n可能的错误信息：\n"+e.getMessage());
            return false;
        } catch (IOException e) {
            //e.printStackTrace();
            textA.setText("找不到服务端啦...\n可能的错误信息：\n" + e.getMessage());
            return false;
        }
        
        if (thread == null){           //建立线程
            thread = new Thread(this); 
            thread.setPriority(Thread.MIN_PRIORITY);
            thread.start();  //启动线程
            return true;
        }else return false;
    }

    @Override
    public void actionPerformed(ActionEvent arg0) {
        // “发送信息” 按钮功能实现
        if (arg0.getSource() == btSend){
            sendMessage();
        }
        
        // 重连服务端的按钮功能实现
        if (arg0.getSource() == btRelink){
            linkToServer(serverIPAddress , portNum);
        }
    }
    
    public void keyPressed(KeyEvent e){
        if (e.getKeyCode() == KeyEvent.VK_ENTER){
            sendMessage();
        }
    }
    @Override
    public void keyReleased(KeyEvent arg0) {}
    @Override
    public void keyTyped(KeyEvent arg0) {}

}