java实现小型局域网群聊功能(C/S模式)

本文实例为大家分享了java群聊功能，供大家参考，具体内容如下

Java 对TCP协议的支持：
--> java.net包中定义了两个类ServerSocket 和Socket ，分别用来实现双向连接的server 端和client 端。 
--> Client 类定义客户端 

package com.dragon.java.tcpchat;

import java.io.IOException;
import java.net.Socket;
import java.net.UnknownHostException;


public class Client {
  public static void main(String args[]) throws UnknownHostException,
      IOException {
    Socket client = new Socket("192.168.1.188", 10000);

    // 穿件发送信息的线程
    new ClientSend(client).start();
    // 创建接收信息的线程
    new ClientReceive(client).start();
　　　　　// 因为要实现聊天功能，而不是只发送一次信息，所以输出流和客户端都不能关闭。
    // client.shutdownOutput();
    // client.close();

  }
}

--> ClientSend 类 定义客户端向服务端发送信息的线程 

package com.dragon.java.tcpchat;

import java.io.IOException;
import java.io.PrintStream;
import java.net.Socket;
import java.util.Scanner;


public class ClientSend extends Thread {
  private Scanner scanner;
  private Socket socket;

  public ClientSend(Socket socket) {
    this.socket = socket;
  }

  @Override
  public void run() {
    scanner = new Scanner(System.in);

    try {
      PrintStream ps = new PrintStream(socket.getOutputStream());
      String line = "";
      // 阻塞式发送信息
      while ((line = scanner.nextLine()) != null) {
 ps.println(line);
      }
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
}

--> ClientReceive 类 定义客户端接收服务端信息的线程 

package com.dragon.java.tcpchat;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.Socket;


public class ClientReceive extends Thread {
  private Socket socket;

  public ClientReceive(Socket socket) {
    this.socket = socket;
  }

  @Override
  public void run() {
    try {
      BufferedReader br = new BufferedReader(new InputStreamReader(
   socket.getInputStream()));
      // 按行接收信息
      String line = "";
      while ((line = br.readLine()) != null) {
 System.out.println(line);
      }
    } catch (Exception e) {
      e.printStackTrace();
    }
  }

}

--> Server 类定义服务端 

package com.dragon.java.tcpchat;

import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.ArrayList;
import java.util.List;


public class Server {
  public static void main(String[] args) throws IOException,
      InterruptedException {
    List list = new ArrayList<>();

    // 创建服务器端的套接字
    ServerSocket server = new ServerSocket(10000);

    while (true) {
      // 接收客户端的阻塞方法
      Socket socket = server.accept();
      // 设计到多个线程可能会对集合进行增删的操作，要进行同步的处理
      synchronized (list) {
 list.add(socket);
      }
      // 启动一个新的线程去处理这个客户端的交流
      new HandleSocket(socket, list).start();
    }
　　　　 // 因为不知道客户端什么时候发送信息，所以服务端要一直开启不能关闭。
  }
}

--> HandleSocket 类对连接到服务端的客户端进行操作(上下线通知、屏蔽拉黑、将信息发送到每个客户端等...) 

package com.dragon.java.tcpchat;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintStream;
import java.net.InetAddress;
import java.net.Socket;
import java.util.List;


public class HandleSocket extends Thread {

  private Socket socket;
  private List list;

  
  public HandleSocket(Socket socket, List list) {
    this.socket = socket;
    this.list = list;
  }

  
  @Override
  public void run() {
    InetAddress address = socket.getInetAddress(); // 获取连接到服务器的这的客户端的地址
    String ip = address.getHostAddress();
    System.out.println(ip + "上线了！");
    if (ip.equals("192.168.1.117")) {
      synchronized (list) {
 sendToAll(ip + "由于违规操作，已被拉入黑名单！");
 list.remove(socket);
      }
      return;
    }

    try {
      BufferedReader br = new BufferedReader(new InputStreamReader(
   socket.getInputStream(), "gbk"));

      String line = "";
      while ((line = br.readLine()) != null) {
 String msg = ip + ":" + line;
 System.out.println(msg); // 输出到服务器端的控制台
 // 把这个客户端说的话，发给其他所有的客户端
 sendToAll(msg);
      }

    } catch (IOException e) {
      // e.printStackTrace();
      System.out.println(ip + "下线了！");
      synchronized (list) {
 list.remove(socket);
      }
    }
  }

  
  private void sendToAll(String msg) {
    synchronized (list) {
      for (Socket s : list) {
 if (s != socket) {
   try {
     PrintStream ps = new PrintStream(s.getOutputStream());
     ps.println();
   } catch (IOException e) {
     e.printStackTrace();
   }
 }
      }
    }
  }

}

--> 注意：因为要实现客户端连接到服务端，即客户端要先找到服务端，所以服务端要先开启，再开启服务端...

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持考高分网。