多人聊天室

1.创建服务面板

package yiduiy;
 
 
import java.awt.BorderLayout;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Set;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
 
public class fuwumianban extends JFrame {
    private JTextArea ta_info;
    private ServerSocket server; // 声明ServerSocket对象
    private Socket socket; // 声明Socket对象socket
    private Hashtable<String, Socket> map = new Hashtable<String, Socket>();// 用于存储连接到服务器的用户和客户端套接字对象
    
    public void createSocket() {
        try {
            server = new ServerSocket(1978);
            while (true) {
                ta_info.append("等待新客户连接......\n");
                socket = server.accept();// 创建套接字对象
                ta_info.append("客户端连接成功。" + socket + "\n");
                new ServerThread(socket).start();// 创建并启动线程对象
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
    class ServerThread extends Thread {
        Socket socket;
        
        public ServerThread(Socket socket) {
            this.socket = socket;
        }
        
        public void run() {
            try {
                BufferedReader in = new BufferedReader(new InputStreamReader(
                        socket.getInputStream()));// 创建输入流对象
                while (true) {
                    String info = in.readLine();// 读取信息
                    String key = "";
                    if (info.startsWith("用户：")) {// 添加登录用户到客户端列表
                        key = info.substring(3, info.length());// 获得用户名并作为键使用
                        map.put(key, socket);// 添加键值对
                        Set<String> set = map.keySet();// 获得集合中所有键的Set视图
                        Iterator<String> keyIt = set.iterator();// 获得所有键的迭代器
                        while (keyIt.hasNext()) {
                            String receiveKey = keyIt.next();// 获得表示接收信息的键
                            Socket s = map.get(receiveKey);// 获得与该键对应的套接字对象
                            PrintWriter out = new PrintWriter(s
                                    .getOutputStream(), true);// 创建输出流对象
                            Iterator<String> keyIt1 = set.iterator();// 获得所有键的迭代器
                            while (keyIt1.hasNext()) {
                                String receiveKey1 = keyIt1.next();// 获得键，用于向客户端添加用户列表
                                out.println(receiveKey1);// 发送信息
                                out.flush();// 刷新输出缓冲区
                            }
                        }
                        
                    } else {// 转发接收的消息
                        key = info.substring(info.indexOf("：发送给：") + 5, info
                                .indexOf("：的信息是："));// 获得接收方的key值,即接收方的用户名
                        String sendUser = info.substring(0, info
                                .indexOf("：发送给："));// 获得发送方的key值,即发送方的用户名
                        Set<String> set = map.keySet();// 获得集合中所有键的Set视图
                        Iterator<String> keyIt = set.iterator();// 获得所有键的迭代器
                        while (keyIt.hasNext()) {
                            String receiveKey = keyIt.next();// 获得表示接收信息的键
                            if (key.equals(receiveKey)
                                    && !sendUser.equals(receiveKey)) {// 如果是发送方，但不是用户本身
                                Socket s = map.get(receiveKey);// 获得与该键对应的套接字对象
                                PrintWriter out = new PrintWriter(s
                                        .getOutputStream(), true);// 创建输出流对象
                                
                                out.println("MSG:"+info);// 发送信息
                                out.flush();// 刷新输出缓冲区
                            }
                        }
                    }
                }
            } catch (IOException e) {
                ta_info.append(socket + "已经退出。\n");
            }
        }
    }
    
  
    public static void main(String args[]) {
        fuwumianban frame = new fuwumianban();
        frame.setVisible(true);
        frame.createSocket();
    }
    
 
    public fuwumianban() {
        super();
        setTitle("多个用户聊天");
        setBounds(100, 100, 385, 266);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        
        final JScrollPane scrollPane = new JScrollPane();
        getContentPane().add(scrollPane, BorderLayout.CENTER);
        
        ta_info = new JTextArea();
        scrollPane.setViewportView(ta_info);
    }
}

2.创建客户面板

package yiduid;
 
 
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;
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 kehuframe extends JFrame {
    private JTextArea ta_info;
    private JTextField tf_send;
    PrintWriter out;// 声明输出流对象
    
    /**
     * Launch the application
     * 
     * @param args
     */
    public static void main(String args[]) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                   kehuframe frame = new kehuframe();
                    frame.setVisible(true);
                    frame.createClientSocket();
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }
    
    public void createClientSocket() {
        try {
            Socket socket = new Socket("127.0.0.1", 1978);// 连接本地1978端口
            out = new PrintWriter(socket.getOutputStream(), true);// 创建输出流对象
            new ClientThread(socket).start();// 创建并启动线程对象
        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
    class ClientThread extends Thread {
        Socket socket;
        
        public ClientThread(Socket socket) {
            this.socket = socket;
        }
        
        public void run() {
            try {
                BufferedReader in = new BufferedReader(new InputStreamReader(
                        socket.getInputStream()));// 创建输入流对象
                while (true) {
                    String info = in.readLine();// 读取信息
                    ta_info.append(info + "\n");// 在文本域中显示信息
                    if (info.equals("88")) {
                        break;// 结束线程
                    }
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    private void send() {
        String info = tf_send.getText();// 获得输入的信息
        if (info.equals("")) {
            return;// 如果没输入信息则返回，即不发送
        }
        if (info.equals("88")) {
            System.exit(0);// 如果没输入信息是88，则退出
        }
        out.println(info);// 发送信息
        out.flush();// 刷新输出缓冲区
        tf_send.setText(null);// 清空文本框
    }
    
   
    public kehuframe() {  //创建面板
        super();
        setTitle("客户互相聊天");
        setBounds(100, 100, 385, 266);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        
        final JPanel panel = new JPanel();
        getContentPane().add(panel, BorderLayout.SOUTH);
        
        final JLabel label = new JLabel();
        label.setText("输入聊天内容：");
        panel.add(label);
        
        tf_send = new JTextField();
        tf_send.addActionListener(new ActionListener() {
            public void actionPerformed(final ActionEvent e) {
                send();
            }
        });
        tf_send.setPreferredSize(new Dimension(180, 25));
        panel.add(tf_send);
        
        final JButton button = new JButton();
        button.addActionListener(new ActionListener() {
            public void actionPerformed(final ActionEvent e) {
                send();
            }
        });
        button.setText("发  送");
        panel.add(button);
        
        final JScrollPane scrollPane = new JScrollPane();
        getContentPane().add(scrollPane, BorderLayout.CENTER);
        
        ta_info = new JTextArea();
        scrollPane.setViewportView(ta_info);
        
    }
    
}

第二种方法

控制台输出

1.服务界面

package duorenliaotian;
 
import java.io.*;
import java.net.*;
import java.util.ArrayList;
public class Server{
    public static ServerSocket server_socket;
    public static ArrayList<Socket> socketList=new ArrayList<Socket>();  
    public static void main(String []args){
        try{
            server_socket = new ServerSocket(5000);
            while(true){
                Socket socket = server_socket.accept();
                socketList.add(socket); //把sock对象加入sock集合
                ServerBO_Thread st=new ServerBO_Thread(socket,socketList); //初始化多线程
                st.start();//启动多线程
            }
        }catch(Exception ex){
            ex.printStackTrace();
        }finally{
            try{
                if(server_socket!=null){
                    server_socket.close();
                }
            }catch(Exception ex){
                ex.printStackTrace();
            }
        }
    }
    public void encryptWrite(String src,DataOutputStream output)throws IOException{
        //将一个字符串转化为字符数组
        //System.out.println(src);
        char[] char_arr = src.toCharArray();
        //加密操作
        for(int i = 0;i<char_arr.length;i++){
            output.writeChar(char_arr[i]+13);
        }
        //用作结束标志符
        output.writeChar(2333);
        output.flush();
    }
    //读取并解密
    public String readDecrypt(DataInputStream input)throws IOException{
        String rtn="";
        while(true){
            int char_src =input.readChar();
            if(char_src!=2333){
                rtn=rtn+(char)(char_src-13);
            }else{
                break;
            }
        }
        return rtn;
    }
}
class ServerBO_Thread extends Thread{
    Socket client = null;
    ArrayList<Socket> clients;
    ServerBO_Thread(Socket s,ArrayList<Socket> ss){//初始化
        client=s;
        clients=ss; 
    }
    public void run(){
        DataInputStream input = null;
        DataOutputStream output =null;
        try{
            input = new DataInputStream(client.getInputStream());
            Server bo = new Server();
            String receive=null;
            String send=null;
            while(true){//监视当前客户端有没有发来消息
                if(!client.isClosed()){
                    receive=bo.readDecrypt(input);
                    clients.trimToSize();
                    String[] param = receive.split("&");
                    if(")start".equals(param[1])){    //分析客户端发来的内容
                        send = param[0]+"进入聊天室";
                    }else{
                        send = param[0]+"说:    "+param[1];
                    }
                    if(!("3333".equals(param[1]))){//3333为退出聊天室信号
                        for(Socket socket:clients){ //遍历socke集合 
                            //把读取到的消息发送给各个客户端  
                            if(!socket.isClosed()){
                                output = new DataOutputStream(socket.getOutputStream());
                                bo.encryptWrite(send,output);
                            }
                        }  
                    }else{//如果有客户端退出
                        for(Socket socket:clients){ //遍历socke集合 
                                if(socket!=client){//告诉其他人此人退出聊天室
                                    if(!(socket.isClosed())){
                                        output = new DataOutputStream(socket.getOutputStream());
                                        bo.encryptWrite(param[0]+"已退出聊天室",output);
                                    }
                                }
                            }
                        output = new DataOutputStream(client.getOutputStream());
                        bo.encryptWrite("3333",output);//返回信号给要退出的客户端，然后关闭线程
                        client.close();
                        input.close();
                        output.close();
                    }
                }else{
                    break;
                }
            }
        }catch(Exception ex){
            ex.printStackTrace();
        }
    }
}

2.客户

package duorenliaotian;
import java.io.IOException;
import java.util.Scanner;
import java.net.*;
import java.io.*;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.io.BufferedWriter;
import java.io.BufferedReader;
import java.io.DataOutputStream;
public class Cilent{
//服务端ip
    public  String ip = "127.0.0.1";
    //服务端端口
    public  int port = 5000;
    public  DataOutputStream output = null;
    public  Socket socket = null;
    public  DataInputStream input = null;
    public  Scanner sc =new Scanner (System.in);
    public  String send ;
    public  String receive;
    public  String name;
    public String sd = null;
    public static void main(String[]aa){
        Cilent po = new Cilent();
        po.start();
    }
    public void start(){
        try{
            System.out.println("*******欢迎使用匿名聊天室！**********");
            System.out.println("请输入你将要使用的昵称：");
            name=sc.nextLine();//获取昵称
            socket = new Socket(ip,port);
            output=new DataOutputStream(socket.getOutputStream());
            input = new DataInputStream(socket.getInputStream());
            send = name+"&)start";//把昵称发送到server 告诉所有人有新成员加入聊天室
            System.out.println("(如果要退出聊天室请输入“3333”！)");
            System.out.println("*******成功进入匿名聊天室！**********");
            System.out.println("");
            encryptWrite(send,output);
            Out out=new Out(output,name,input,socket);
            out.start();//启动发送聊天内容的多线程
            while(true){    
                String receive = readDecrypt(input);
                if("3333".equals(receive)){//如果收到“3333”则退出聊天室
                    System.out.println("*******成功退出匿名聊天室！**********");
                    input.close();
                    output.close();
                    socket.close();
                    System.exit(0);
                }
                System.out.println(receive);
            }
        }catch(Exception ex){
                ex.printStackTrace();
        }finally{
            try{
                if(socket!=null) socket.close();
                input.close();
                output.close();
            }catch(Exception ex){
                ex.printStackTrace();
            }
        }    
    }
    public void encryptWrite(String src,DataOutputStream output)throws IOException{
        //将一个字符串转化为字符数组
        char[] char_arr = src.toCharArray();
        //加密操作
        for(int i = 0;i<char_arr.length;i++){
            output.writeChar(char_arr[i]+13);
        }
        //用作结束标志符
        output.writeChar(2333);
        output.flush();
    }
    //读取并解密
    public String readDecrypt(DataInputStream input)throws IOException{
        String rtn="";
        while(true){
            int char_src =input.readChar();
            if(char_src!=2333){
                rtn=rtn+(char)(char_src-13);
            }else{
                break;
            }
        }
        return rtn;
    }
}
class Out extends Thread {
    public DataOutputStream output;
    public DataInputStream input;
    public static String name;
    public Socket socket;
    public  Scanner sc =new Scanner (System.in);
    Out(DataOutputStream ot,String n,DataInputStream it,Socket socket){
        output=ot;
        input=it;
        name=n;
    }
    public void run(){
        Cilent po = new Cilent();
        try{
            while(true){
                String send=sc.nextLine();//获取用户输入
                String send2=name+"&"+send;//把聊天内容打包成约定形式
                po.encryptWrite(send2,output);
            }
        }catch(Exception ex){
            ex.printStackTrace();
        }finally{
            System.out.println("sfef");
        }
    }
}