[Java小程序]聊天室——Socket和ServerSocket的使用

这段小代码是因为担任Java助教给刚学习Java的本科大二的小学弟小学妹们指导，他们的实验作业就是编写一个Java聊天室客户端和服务器，为了避免出纰漏，自己事先写了一下。

客户端Ui代码：

package com.CS;

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.GridBagLayout;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;

public class Client_UI extends JFrame{
    public JButton Connect;         //创建连接按钮；
    public JButton Say;             //创建发送按钮；
    public JPanel  Panel;           //创建一个用于存放所有组件的容器；
    public JPanel  Panel_up;        //创建一个用于存放界面最上面各个组件的容器；
    public JPanel  Panel_down;      //创建一个用于存放界面最下面各个组件的容器；
    public JTextField Server_IP;    //用于写IP地址的组件；
    public JTextField Server_Port;  //用于写端口号的组件；
    public JTextField Say_Send;     //用于写要发送的文字的内容的组件；
    public JTextArea  Text_Show;    //用于显示相关信息的组件；

    public Client_Thread Server;    //创建一个客户端线程；

    public Client_UI(){
        Connect=new JButton("Connect");
        Say=new JButton("Say");
        Server_IP=new JTextField(10);
        Server_Port=new JTextField(5);
        Say_Send=new JTextField(25);

        Text_Show=new JTextArea();
        JScrollPane ScrollPane=new JScrollPane();  //使之可以滚动，且设置滚动一直存在；
        ScrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
        ScrollPane.setViewportView(Text_Show);

        Panel_up=new JPanel();
//        Panel_up.setLayout(new GridLayout(1,5));
//        Panel_up.setLayout(new FlowLayout(FlowLayout.LEFT));
        Panel_up.setLayout(new GridBagLayout());        //布局方法，调试得出该布局方法最合理；
        Panel_up.add(new JLabel("Server IP"));
        Panel_up.add(Server_IP);
        Panel_up.add(new JLabel("Server Port"));
        Panel_up.add(Server_Port);
        Panel_up.add(Connect);

        Panel_down=new JPanel();
//        Panel_down.setLayout(new GridLayout(1,3));
        Panel_down.setLayout(new FlowLayout(FlowLayout.LEFT));        //布局方法，调试得知，从左边最先开始存放组件。
        Panel_down.add(new JLabel("Say"));
        Panel_down.add(Say_Send);
        Panel_down.add(Say);

        Panel=new JPanel();
        Panel.setLayout(new BorderLayout());
        Panel.add(Panel_up, BorderLayout.NORTH);
        Panel.add(ScrollPane);
        Panel.add(Panel_down,BorderLayout.SOUTH);

        this.setTitle("客户端");
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setSize(400, 300);
        this.setLocation(600, 200);
        this.add(Panel);
        this.setVisible(true);

        //对connect按钮增加监听；
        Connect.addActionListener(new ActionListener(){
            @Override
            public void actionPerformed(ActionEvent e) {
                Server=new Client_Thread(Client_UI.this);
            }
        });

        //对Say按钮增加监听；
        Say.addActionListener(new ActionListener(){
            @Override
            public void actionPerformed(ActionEvent e) {
                Server.SendMessage(Say_Send.getText());
                Say_Send.setText("");
            }
        });
    }

    public static void main(String args[]){
        Client_UI clientui=new Client_UI();
    }

}

客户端线程代码：

package com.CS;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
//import java.io.PrintWriter;
import java.net.Socket;

public class Client_Thread extends Thread {
    Client_UI UI;
    Socket client_socket;
    BufferedReader Read;
    PrintStream Write;

    public Client_Thread(Client_UI ui){
        this.UI=ui;
        String IP=UI.Server_IP.getText().trim();     //获取IP地址；
        int Port=Integer.parseInt(UI.Server_Port.getText().trim());   //获取端口号，并将其转换成int型;
        try {
            client_socket=new Socket(IP,Port);  //设置连接服务器的IP地址和端口号；
            Println("客户端连接服务器成功！");
            Read=new BufferedReader(new InputStreamReader(client_socket.getInputStream()));
            Write=new PrintStream(client_socket.getOutputStream());
        } catch (IOException e) {
            Println("客户端连接服务器失败！");
            e.printStackTrace();
        } 

        new Thread(new Runnable(){
            @Override
            public void run() {
                String  message="";
                while(true){
                    try {
                        message=Read.readLine();
                    } catch (IOException e) {
                        Println("连接服务器中断！");
                        e.printStackTrace();
                        break;
                    }
                    if(message!=null&&message.trim()!=""){
                        Println(message);
                    }
                }
            }
        }).start();
    }

    public void Println(String s){
        if(s!=null){
            this.UI.Text_Show.setText(this.UI.Text_Show.getText()+s+"\n");
            System.out.println(s + "\n");
        }
    }

    public void SendMessage(String text){
        try{
            Write.println(text);
        }catch(Exception e){
            Println(e.toString());
        }
    }

}

服务器UI代码：

package com.Server;

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.net.Socket;
import java.util.List;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;

public class Server_UI extends JFrame{
    public JButton Start;
    public JButton Say;
    public JTextField Port_Msg;
    public JTextField Say_Msg;
    public JPanel Panel_up;
    public JPanel Panel;
    public JPanel Panel_down;
    public JTextArea Text_show;
    public Server server;
    public List<Socket> clients;     //保存服务器接收到的客户端;

    public Server_UI(){
        Start=new JButton("Start");
        Say=new JButton("Say");

        Port_Msg=new JTextField(25);
        Say_Msg=new JTextField(25);

        Text_show=new JTextArea();
        JScrollPane ScrollPane=new JScrollPane();
        ScrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
        ScrollPane.setViewportView(Text_show);

        Panel_up=new JPanel();
        Panel_up.setLayout(new FlowLayout());
        Panel_up.add(new JLabel("Port"));
        Panel_up.add(Port_Msg);
        Panel_up.add(Start);

        Panel_down=new JPanel();
        Panel_down.setLayout(new FlowLayout());
        Panel_down.add(new JLabel("Say"));
        Panel_down.add(Say_Msg);
        Panel_down.add(Say);

        Panel=new JPanel();
        Panel.setLayout(new BorderLayout());
        Panel.add(Panel_up, BorderLayout.NORTH);
        Panel.add(ScrollPane,BorderLayout.CENTER);
        Panel.add(Panel_down,BorderLayout.SOUTH);

        this.setTitle("服务器");
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setSize(400, 300);
        this.setLocation(100, 200);
        this.add(Panel);
        this.setVisible(true);

        //设置Start监听器；
        Start.addActionListener(new ActionListener(){
            @Override
            public void actionPerformed(ActionEvent e) {
                server=new Server(Server_UI.this);
            }
        });

        //设置Say监听器;
        Say.addActionListener(new ActionListener(){
            @Override
            public void actionPerformed(ActionEvent e) {
                server.Send_Message(Say_Msg.getText());
                Say_Msg.setText("");
            }
        });
    }

    public static void main(String args[]){
        Server_UI serverUI=new Server_UI();
    }
}

服务器线程代码：

package com.Server;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;

public class Server extends Thread{
    Server_UI ui;
    BufferedReader Read;
    PrintStream  Write;
    ServerSocket server;
    public Server(Server_UI UI){
        this.ui=UI;
        //设置服务器的端口；
        int port=Integer.parseInt(ui.Port_Msg.getText().trim());
        try {
            server=new ServerSocket(port);
            Println("端口设置成功！");
        } catch (IOException e) {
            Println("端口设置失败！");
            e.printStackTrace();
        }
        this.ui.clients=new ArrayList<Socket>();

        //创建一个线程，用来等待客户端的连接；
        new Thread(new Runnable(){
            @Override
            public void run() {
                    while(true){
                        Println("等待客户端接入...");
                        Socket Client = null;
                        try {
                            Client = server.accept();
                            ui.clients.add(Client);
                            Println("成功连接到客户端"+Client.toString());
                            new ListenClient(ui,Client);
                        } catch (IOException e) {
                            Println("连接客户端失败！");
                            Println(Client.toString());
                            e.printStackTrace();
                        }
                    }

            }
        }).start();
    }

    public synchronized void Send_Message(String s){
        for(int i=0;i<this.ui.clients.size();i++){
            Socket client=ui.clients.get(i);
            try {
                Write=new PrintStream(client.getOutputStream());
                Write.println(s);
            } catch (IOException e) {
                Println(e.toString());
                e.printStackTrace();
            }
        }
    }

    public void Println(String s){
        if(s!=null){
            this.ui.Text_show.setText(this.ui.Text_show.getText()+s+"\n");
            System.out.println(s + "\n");
        }
    }
}

class ListenClient extends Thread{
    public Server_UI ui;
    public Socket client;
    BufferedReader Read;
    PrintStream  Write;
    public ListenClient(Server_UI UI,Socket Client){
        this.ui=UI;
        this.client=Client;
        //创建一个接受数据的线程；
        new Thread(new Runnable(){
            @Override
            public void run() {
                String message="";
                while(true){
                    try {
                        Read=new BufferedReader(new InputStreamReader(client.getInputStream()));
                        message=Read.readLine();
                        Println(message);
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }

            }

        }).start();
    }
    public void Println(String s){
        if(s!=null){
            this.ui.Text_show.setText(this.ui.Text_show.getText()+s+"\n");
            System.out.println(s + "\n");
        }
    }
}