Java多线程实现多人聊天室功能

package works;

import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

public class ServerChat {

 //定义Map集合用于存储用户的Socket以及用户的名字   key:Socket    Value:用户名
 public final static Map<Socket,String> socketsMaps = Collections.synchronizedMap(new HashMap<Socket,String>());
 public static void main(String[] args) {
  // TODO Auto-generated method stub
  try {
   // 创建服务端套接字
   ServerSocket serverSocket = new ServerSocket(9999); 
System.out.println("------服务端暴露-------");
   while (true) {
    // 监听客户端套接字，若有客户端连接，则代码不会往下执行，否则会堵塞在此处。
    Socket socket = serverSocket.accept();

    // 开启线程，用于读取客户端发送的信息，并转发给每一个客户端
    new ThreadServer(socket).start();
   }
  } catch (Exception e) {
   // TODO: handle exception
   e.printStackTrace();
  }
 }
}

class ThreadServer extends Thread {
 private Socket socket;
 ThreadServer(){};
 ThreadServer(Socket socket)
 {
  this.socket = socket;
 }
 @Override
 public void run() {
  try {
   while(true)
   {
    DataInputStream dataInputStream = new DataInputStream(socket.getInputStream());
    String data = dataInputStream.readUTF();
    
    if(data.startsWith("①②③④")&&data.endsWith("①②③④"))
    {
     //发送过来的是用户名
     //将Socket以及用户名字都存放在Map集合中
     ServerChat.socketsMaps.put(socket, data.replace("①②③④",""));
     //获取所有的key(Socket)，将所有用户的名字发送至客户端
     Set<Socket> sockets = ServerChat.socketsMaps.keySet();
     //获取所有的用户的名字，将这些名字拼装成一个字符串
     Collection<String> names = ServerChat.socketsMaps.values();
     StringBuffer sbf = new StringBuffer();
     for(String userName :names)
     {
      sbf.append(userName).append(",");
     }
     System.out.println("sbf:"+sbf.toString());
     for(Socket soc:sockets)
     {
      DataOutputStream dataOutputStream = new DataOutputStream(soc.getOutputStream());
      dataOutputStream.writeUTF("①②③④"+sbf.toString()+"①②③④");
      dataOutputStream.flush();
     }
    }
    else{
     //发送过来的是聊天信息
     //获取所有的key(Socket)，将所有用户的名字发送至客户端
     Set<Socket> sockets = ServerChat.socketsMaps.keySet();
     //將聊天信息广播出去
     for(Socket soc:sockets)
     {
      DataOutputStream dataOutputStream = new DataOutputStream(soc.getOutputStream());
      dataOutputStream.writeUTF("[ "+ServerChat.socketsMaps.get(socket)+" ]说："+data);
      dataOutputStream.flush();
     }
     
     
    }
    
   }
  } catch (IOException e) {
   // TODO Auto-generated catch block
   e.printStackTrace();
  }
 }
}

package works;

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.Socket;

import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;

public class ClientChat {

 private JFrame mainWin = new JFrame("聊天窗口");

 // 消息展示框
 private JTextArea displayTa = new JTextArea(14, 40);
 // 在线用户名称展示框
 private DefaultListModel<String> userListModel = new DefaultListModel<>();
 private JList<String> userList = new JList<>(userListModel);
 // 消息发送框
 private JTextArea inputTF = new JTextArea(4, 40);
 // 消息按钮
 private JButton sendBn = new JButton("发送");
 // 用户记录当前聊天用户名
 private String curUser;

 public static void main(String[] args) {
  new ClientChat().init();
 }

 private void init() {
  try {
   // 通过弹出对话框获取用户输入的用户名
   String userName = JOptionPane.showInputDialog(mainWin, "请输入您的用户名：");
   // 把用户输入的用户名，赋给curUser
   curUser = userName;
   mainWin.setTitle(curUser + "的聊天窗口");

   // 创建套接字
   Socket socket = new Socket("192.168.193.1", 9999);
   // 向服务器声明
   DataOutputStream dataOutputStream = new DataOutputStream(socket.getOutputStream());
   //发送用户名到服务端
   dataOutputStream.writeUTF("①②③④"+userName+"①②③④");
   dataOutputStream.flush();

   // 开启线程，用于读取服务器发送的信息
   new ThreadClient(socket, this).start();

   JPanel bottomPanel = new JPanel();

   // 将消息框和按钮添加到窗口的底端
   mainWin.add(bottomPanel, BorderLayout.SOUTH);
   bottomPanel.add(inputTF);
   bottomPanel.add(sendBn);

   ActionListener listener = new ActionListener() {
    @Override
    public void actionPerformed(ActionEvent e) {
     // 获取用户发送的消息
     String message = inputTF.getText();
     sendSms(message,socket);
    }
   };
   // 给发送消息按钮绑定点击事件监听器
   sendBn.addActionListener(listener);

   JPanel centerPanel = new JPanel();

   // 将展示消息区centerPanel添加到窗口的中间
   mainWin.add(centerPanel);
   // 让展示消息区可以滚动
   centerPanel.add(new JScrollPane(displayTa));
   displayTa.setEditable(false);
   // 用户列表和是否私聊放到窗口的最右边
   Box rightBox = new Box(BoxLayout.Y_AXIS);
   userList.setFixedCellWidth(60);
   userList.setVisibleRowCount(13);
   rightBox.add(new JLabel("用户列表："));
   rightBox.add(new JScrollPane(userList));

   centerPanel.add(rightBox);

   // 关闭窗口退出当前程序
   mainWin.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   mainWin.pack(); // swing加上这句就可以拥有关闭窗口的功能
   mainWin.setVisible(true);

  } catch (Exception e) {
   // TODO: handle exception
   e.printStackTrace();
  }
 }
  //点击发送后将消息发送到服务器
  protected void sendSms(String sms, Socket socket) {
   try {
    //发送聊天消息到服务端
    DataOutputStream dataOutputStream = new DataOutputStream(socket.getOutputStream());
    dataOutputStream.writeUTF(sms);
    dataOutputStream.flush(); 
     
   } catch (Exception e) {
    // TODO: handle exception
    e.printStackTrace();
   }
  }

  public DefaultListModel<String> getUserListModel() {
   return userListModel;
  }

  public JTextArea getDisplayTa() {
   return displayTa;
  }
  public JTextArea getInputTF()
  {
   return inputTF;
  }
}

// 定义线程类，用来读取服务器发送的信息
class ThreadClient extends Thread {
 private Socket socket;
 private ClientChat clientChat;

 ThreadClient() {
 }

 ThreadClient(Socket socket, ClientChat clientChat) {
  this.socket = socket;
  this.clientChat = clientChat;
 }

 @Override
 public void run() {

  try {
   while (true) {
    DataInputStream DataInputStream = new DataInputStream(socket.getInputStream());
    String message = DataInputStream.readUTF();

    if(message.startsWith("①②③④")&&message.endsWith("①②③④"))
    {
     //说明信息是用户名
     String[] names = message.replace("①②③④","").split(",");
     // 将用户列表先清空
     clientChat.getUserListModel().clear();
     for (int i = 0; i < names.length; ++i) {
      clientChat.getUserListModel().addElement(names[i]);
     }
    }
    else
    {
     //说明是聊天信息，将聊天信息放在displayTa中
     clientChat.getInputTF().setText("");
     clientChat.getDisplayTa().append(message+"\t\n");
    }

    
   }
  } catch (IOException e) {
   // TODO Auto-generated catch block
    e.printStackTrace();
   }
  }
}