Java通过Socket实现简单多人聊天室

import java.io.bufferedreader;

import java.io.ioexception;

import java.io.inputstreamreader;

import java.io.printwriter;

import java.net.socket;

public class client{

  public static void main(string[] args) throws ioexception {

  //创建连接指定ip和端口的socket

  socket socket = new socket( "127.0.0.1" , 5200 );

  //获取系统标准输入流

  bufferedreader reader = new bufferedreader( new inputstreamreader(system.in));

  printwriter out = new printwriter(socket.getoutputstream());

  bufferedreader in = new bufferedreader( new inputstreamreader(socket.getinputstream()));

  //创建一个线程用于读取服务器的信息

  new thread( new runnable() {

   @override

   public void run() {

   try {

    while ( true ){

    system.out.println(in.readline());

    }

   } catch (ioexception e) {

    e.printstacktrace();

   }

   }

  }).start();

  //写信息给客户端

  string line = reader.readline();

  while (! "end" .equalsignorecase(line)){

   //将从键盘获取的信息给到服务器

   out.println(line);

   out.flush();

   //显示输入的信息

   line = reader.readline();

  }

  out.close();

  in.close();

  socket.close();

  }

}

import java.io.ioexception;

import java.net.serversocket;

import java.net.socket;

import java.util.list;

import java.util.vector;

public class servers {

  //将接收到的socket变成一个集合

  protected static list<socket> sockets = new vector<>();

  public static void main(string[] args) throws ioexception {

  //创建服务端

  serversocket server = new serversocket( 5200 );

  boolean flag = true ;

  //接受客户端请求

  while (flag){

   try {

   //阻塞等待客户端的连接

   socket accept = server.accept();

   synchronized (sockets){

   sockets.add(accept);

   }

   //多个服务器线程进行对客户端的响应

   thread thread = new thread( new serverthead(accept));

   thread.start();

   //捕获异常。

   } catch (exception e){

   flag = false ;

   e.printstacktrace();

   }

  }

  //关闭服务器

  server.close();

  }

}

import java.io.bufferedreader;

import java.io.ioexception;

import java.io.inputstreamreader;

import java.io.printwriter;

import java.net.socket;

/**

  * 服务器线程，主要来处理多个客户端的请求

  */

public class serverthead extends servers implements runnable{

  socket socket;

  string socketname;

  public serverthead(socket socket){

  this .socket = socket;

  }

  @override

  public void run() {

  try {

   bufferedreader reader = new bufferedreader( new inputstreamreader(socket.getinputstream()));

   //设置该客户端的端点地址

   socketname = socket.getremotesocketaddress().tostring();

   system.out.println( "client@" +socketname+ "已加入聊天" );

   print( "client@" +socketname+ "已加入聊天" );

   boolean flag = true ;

   while (flag)

   {

   //阻塞，等待该客户端的输出流

   string line = reader.readline();

   //若客户端退出，则退出连接。

   if (line == null ){

    flag = false ;

    continue ;

   }

   string msg = "client@" +socketname+ ":" +line;

   system.out.println(msg);

   //向在线客户端输出信息

   print(msg);

   }

   closeconnect();

  } catch (ioexception e) {

   try {

   closeconnect();

   } catch (ioexception e1) {

   e1.printstacktrace();

   }

  }

  }

  /**

  * 向所有在线客户端socket转发消息

  * @param msg

  * @throws ioexception

  */

  private void print(string msg) throws ioexception {

  printwriter out = null ;

  synchronized (sockets){

  for (socket sc : sockets){

   out = new printwriter(sc.getoutputstream());

   out.println(msg);

   out.flush();

  }

  }

  }

  /**

  * 关闭该socket的连接

  * @throws ioexception

  */

  public void closeconnect() throws ioexception {

  system.out.println( "client@" +socketname+ "已退出聊天" );

  print( "client@" +socketname+ "已退出聊天" );

  //移除没连接上的客户端

  synchronized (sockets){

   sockets.remove(socket);

  }

  socket.close();

  }

}