java基于NIO实现群聊模式

本文实例为大家分享了java基于nio实现群聊模式的具体代码，供大家参考，具体内容如下

client

package com.qst.chat;

import java.io.ioexception;
import java.net.inetsocketaddress;
import java.nio.bytebuffer;
import java.nio.channels.selectionkey;
import java.nio.channels.selector;
import java.nio.channels.socketchannel;
import java.util.iterator;
import java.util.scanner;

public class groupchatclient {
 private final int port = 9999;
 private final string host = "localhost";
 private socketchannel channel;
 private static selector selector;

 private string name;
 
 public groupchatclient() throws ioexception {

  selector = selector.open();
  // 连接服务器
  channel = socketchannel.open(new inetsocketaddress(host, port));
  // 设置非阻塞
  channel.configureblocking(false);
  // 将channel 注册到selector
  channel.register(selector, selectionkey.op_read);
   name = channel.getlocaladdress().tostring().substring(1);

  system.out.println(name + "is ok ....");

 }
 // 向服务器发送消息
 public void sendto(string msg) {
  
  bytebuffer buffer = bytebuffer.wrap((name+":"+msg).getbytes());
  try {
   channel.write(buffer);
  } catch (ioexception e) {
   // todo auto-generated catch block
   e.printstacktrace();
  }

 }
 // 读取从服务器端回复的消息
 public static void getinfo() {
  
  try {
   if(selector.select() >0) {
    iterator<selectionkey> iterator = selector.selectedkeys().iterator();
    
    while(iterator.hasnext()) {
     selectionkey key = iterator.next();
     
     if(key.isreadable()) {
     // 得到通道
     socketchannel sc =  (socketchannel) key.channel();
     
     bytebuffer buffer = bytebuffer.allocate(1024);
     
     int len;
     
     // 把读到的缓冲区的数据转成字符串
     while((len = sc.read(buffer)) > 0) {
      system.out.println(new string(buffer.array()));
     }
     
     }
  
     
    }
    // 删除当前的selectionkey, 防止重复操作
    iterator.remove();
    
   }
  } catch (ioexception e) {
   // todo auto-generated catch block
   e.printstacktrace();
  }
  
 }
 
 public static void main(string[] args) {
  try {
   groupchatclient client = new groupchatclient();
   
   
   new thread() {
    
    
    public void run() {
     while(true)
     {
      try {
       thread.sleep(3000);
       groupchatclient.getinfo();
      } catch (interruptedexception e) {
       // todo auto-generated catch block
       e.printstacktrace();
      }
     }
     
    };
   }.start();
   
   
   scanner sc = new scanner(system.in);
//   while(true) {
//    string name = sc.nextline();
//    client.sendto(name);
//   }
   while(sc.hasnextline()) {
      string s = sc.nextline();
              client.sendto(s);
   }
   
  } catch (ioexception e) {
   // todo auto-generated catch block
   e.printstacktrace();
  }
 }

}

server端

package com.qst.chat;

import java.io.ioexception;
import java.net.inetaddress;
import java.net.inetsocketaddress;
import java.net.serversocket;
import java.net.socket;
import java.nio.bytebuffer;
import java.nio.channels.selectablechannel;
import java.nio.channels.selectionkey;
import java.nio.channels.selector;
import java.nio.channels.serversocketchannel;
import java.nio.channels.socketchannel;
import java.time.chrono.isochronology;
import java.util.iterator;

import com.sun.accessibility.internal.resources.accessibility;

import sun.print.resources.serviceui;

public class groupchatserver {

 private static serversocketchannel socketchannel;
 private static socket socket;
 private static selector selector;
 private static socketchannel accept;

 public groupchatserver() throws ioexception {

  socketchannel = serversocketchannel.open();

  selector = selector.open();
  // 绑定端口
  socketchannel.socket().bind(new inetsocketaddress(9999));
  // 设置非阻塞模式
  socketchannel.configureblocking(false);

  // 将该通道 注册到selector
  socketchannel.register(selector, selectionkey.op_accept);

 }

 // 监听
 public static void listen() {
  system.out.println("监听线程: " + thread.currentthread().getname());
  try {
   while (selector.select() > 0) {

    iterator<selectionkey> iterator = selector.selectedkeys().iterator();

    if (iterator.hasnext()) {
     // 遍历得到selectionkey 集合
     selectionkey next = iterator.next();
     if (next.isacceptable()) {
      next.channel();
      // socketchannel = (serversocketchannel) next.channel();
      socketchannel accept = socketchannel.accept();
      accept.configureblocking(false);

      accept.register(selector, selectionkey.op_read);

       system.out.println(accept.getremoteaddress()+" 上线 了。。。");
     }
     if (next.isreadable()) {
      readdate(next);

     }

     // 移除当前的next，防止重复处理
     iterator.remove();
     // system.out.println("未发现");

    }

   }
  } catch (ioexception e) {
   // todo auto-generated catch block
   e.printstacktrace();
  }

 }

 // 读取客户端消息
 public static void readdate(selectionkey key) {

  try {
   accept = (socketchannel) key.channel();
   bytebuffer buffer = bytebuffer.allocate(1024);
   int len = accept.read(buffer);
   if (len > 0) {
    buffer.flip();
    string msg = new string(buffer.array());
    system.out.println("user = " + msg);

    // 向其它的客户端转发消息(去掉自己)
    sendtoall(msg, accept);
    buffer.clear();
   }
  } catch (ioexception e) {
   // todo auto-generated catch block
   try {
    string msg = accept.getremoteaddress().tostring();
    // 取消注册
    key.cancel();
    // 关闭通道
    accept.close();
    system.out.println(msg + "离线了");
   } catch (ioexception e1) {
    // todo auto-generated catch block
    e1.printstacktrace();
   }
   // e.printstacktrace();
  } finally {
   // todo: handle finally clause
  }
 }

 public static void sendtoall(string msg, socketchannel ssc) {
  for (selectionkey ss : selector.keys()) {
   // 通过 key 取出对应的 socketchannel
   selectablechannel channel = ss.channel();

   // 排除自己
   if (channel instanceof socketchannel && channel != ssc) {
    // 转型
    socketchannel sh = (socketchannel) channel;
    // 转存到buffer
    bytebuffer wrap = bytebuffer.wrap(msg.getbytes());
    try {
     // 写入通道
     sh.write(wrap);
    } catch (ioexception e) {
     // todo auto-generated catch block
     e.printstacktrace();
    }
   }
  }
 }

 public static void main(string[] args) throws ioexception {
  groupchatserver server = new groupchatserver();
  groupchatserver.listen();

 }

}

key.isacceptable()进行接入 操作的时候， 获取通道有两种方式

1、 通过selector获取 (selector key) socketchannel = (serversocketchannel) key.channel();
建立连接 socketchannel .accept();

2、定义一个全局变量

在进行初始化的时候，存储（socketchannel = serversocketchannel.open();）
建立连接 socketchannel .accept();

key.isreadable() 当进行到读入操作的时候（ ） selectionkey key accept = (socketchannel) key.channel();

演示

服务器启动，客户端启动

客户端发送消息

启动第二个客户端

两个客户端相互通信

离线信息显示

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。