使用JavaWeb webSocket实现简易的点对点聊天功能实例代码

首先给大家声明一点：需要 jdk 7 ， tomcat需要支持websocket的版本 

1.initservlet

   该类主要是用来初始化构造将来存储用户身份信息的map仓库，利用其初始化方法init 初始化仓库， 利用其静态方法getsocketlist 获得对应的用户身份信息。

   websocket ，我认为messageinbound 用来识别登录人的信息，用它来找到对应的人，推送消息。每次登录都会产生一个messageinbound。

  这里的 hashmap<string,messageinbound>    ：string 存储用户session的登录id,messageinbound存储 推送需要的身份信息。以上属于个人口头话理解。

package socket;
 import java.nio.charbuffer;
 import java.util.arraylist;
 import java.util.hashmap;
 import java.util.list;
 import javax.servlet.servletconfig;
 import javax.servlet.servletexception;
 import javax.servlet.http.httpservlet;
 import org.apache.catalina.websocket.messageinbound;
 public class initservlet extends httpservlet {
   private static final long serialversionuid = -l; 
   //private static list<messageinbound> socketlist;  
   private static hashmap<string,messageinbound> socketlist;  
   public void init(servletconfig config) throws servletexception {  
 //    initservlet.socketlist = new arraylist<messageinbound>();  
     initservlet.socketlist = new hashmap<string,messageinbound>();  
     super.init(config);  
     system.out.println("server start============");  
   }  
   public static hashmap<string,messageinbound> getsocketlist() {  
     return initservlet.socketlist;  
   }  
 /*  public static list<messageinbound> getsocketlist() {  
     return initservlet.socketlist;  
   }  
 */}

2.mywebsocketservlet 

  websocket用来建立连接的servlet，建立连接时，首先在session获取该登录人的userid，在调用mymessageinbound构造函数传入userid

package socket;
 import java.io.ioexception;
 import java.io.printwriter;
 import java.nio.charbuffer;
 import javax.servlet.servletexception;
 import javax.servlet.http.httpservlet;
 import javax.servlet.http.httpservletrequest;
 import javax.servlet.http.httpservletresponse;
 import org.apache.catalina.websocket.streaminbound;
 import org.apache.catalina.websocket.websocketservlet;
 /**
 * 
 * @classname: mywebsocketservlet 
 * @description: 建立连接时创立 
 * @author mangues
 * @date --
 */
 public class mywebsocketservlet extends websocketservlet {
   public string getuser(httpservletrequest request){ 
     string username = (string) request.getsession().getattribute("user");
     if(username==null){
       return null;
     }
     return username; 
    // return (string) request.getattribute("user"); 
   } 
   @override
   protected streaminbound createwebsocketinbound(string arg,
       httpservletrequest request) {
     system.out.println("##########"); 
     return new mymessageinbound(this.getuser(request)); 
   }
 } 

3.onopen方法调用initservlet的map身份仓库，

放入用户userid 和 对应该登录用户的websocket身份信息messageinbound （可以用userid来寻找到推送需要的 身份messageinbound ）

 ontextmessage ：用来获取消息，并发送消息

package socket;
 import java.io.ioexception;
 import java.nio.bytebuffer;
 import java.nio.charbuffer;
 import java.util.hashmap;
 import org.apache.catalina.websocket.messageinbound;
 import org.apache.catalina.websocket.wsoutbound;
 import util.messageutil;
 public class mymessageinbound extends messageinbound {
   private string name;
   public mymessageinbound() {
     super();
   }
   public mymessageinbound(string name) {
     super();
     this.name = name;
   }
   @override 
   protected void onbinarymessage(bytebuffer arg) throws ioexception { 
     // todo auto-generated method stub 
   } 
   @override 
   protected void ontextmessage(charbuffer msg) throws ioexception { 
     //用户所发消息处理后的map
     hashmap<string,string> messagemap = messageutil.getmessage(msg);  //处理消息类
     //上线用户集合类map
     hashmap<string, messageinbound> usermsgmap = initservlet.getsocketlist();
     string fromname = messagemap.get("fromname");  //消息来自人 的userid
     string toname = messagemap.get("toname");     //消息发往人的 userid
     //获取该用户
     messageinbound messageinbound = usermsgmap.get(toname);  //在仓库中取出发往人的messageinbound
     if(messageinbound!=null){   //如果发往人 存在进行操作
       wsoutbound outbound = messageinbound.getwsoutbound(); 
       string content = messagemap.get("content"); //获取消息内容
       string msgcontentstring = fromname + "   " + content;  //构造发送的消息
       //发出去内容
       charbuffer tomsg = charbuffer.wrap(msgcontentstring.tochararray());
       outbound.writetextmessage(tomsg); //
       outbound.flush();
     }
    /* for (messageinbound messageinbound : initservlet.getsocketlist()) { 
       charbuffer buffer = charbuffer.wrap(msg); 
       wsoutbound outbound = messageinbound.getwsoutbound(); 
       outbound.writetextmessage(buffer); 
       outbound.flush(); 
     } */
   } 
   @override 
   protected void onclose(int status) { 
     initservlet.getsocketlist().remove(this); 
     super.onclose(status); 
   } 
   @override 
   protected void onopen(wsoutbound outbound) { 
     super.onopen(outbound); 
     //登录的用户注册进去
     if(name!=null){
       initservlet.getsocketlist().put(name, this); 
     }
 //    initservlet.getsocketlist().add(this); 
   } 
 }

4.消息处理类，处理前端发来的消息

 package util;
 import java.nio.charbuffer;
 import java.util.hashmap;
 /**
  * 
  * @classname: messageutil 
  * @description: 消息处理类
  * @author mangues
 * @date --
 */
 public class messageutil {
   public static hashmap<string,string> getmessage(charbuffer msg) {
     hashmap<string,string> map = new hashmap<string,string>();
     string msgstring = msg.tostring();
     string m[] = msgstring.split(",");
     map.put("fromname", m[]);
     map.put("toname", m[]);
     map.put("content", m[]);
     return map;
   }
 }

5.web配置

<?xml version="1.0" encoding="utf-8"?>
<web-app version="3.0" 
  xmlns="http://java.sun.com/xml/ns/javaee" 
  xmlns:xsi="http://www.w3.org/2001/xmlschema-instance" 
  xsi:schemalocation="http://java.sun.com/xml/ns/javaee 
  http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
 <servlet> 
  <servlet-name>mywebsocket</servlet-name> 
  <servlet-class>socket.mywebsocketservlet</servlet-class> 
 </servlet> 
 <servlet-mapping> 
  <servlet-name>mywebsocket</servlet-name> 
  <url-pattern>*.do</url-pattern> 
 </servlet-mapping> 
 <servlet> 
  <servlet-name>initservlet</servlet-name> 
  <servlet-class>socket.initservlet</servlet-class> 
  <load-on-startup>1</load-on-startup> 
 </servlet> 
 <welcome-file-list>
  <welcome-file>index.jsp</welcome-file>
 </welcome-file-list>
</web-app>

6,前端，为方便起见，我直接用了两个jsp，在其中用<%session.setattribute("user","小明")%>；来表示登录。

      两个jsp没任何本质差别，只是用来表示两个不同的人登录，可以同两个浏览器打开不同的jsp，来聊天操作

   a.小化

<%@ page language="java" contenttype="text/html; charset=utf-"
   pageencoding="utf-"%>
 <!doctype html>
 <html>
 <head>
 <meta http-equiv="content-type" content="text/html; charset=utf-">
 <title>index</title>
 <script type="text/javascript" src="js/jquery ...min.js"></script>
 <%session.setattribute("user", "小化");%>
 <script type="text/javascript">
 var ws = null;
 function startwebsocket() {
   if ('websocket' in window)
     ws = new websocket("ws://localhost:/websocket/mywebsocket.do");
   else if ('mozwebsocket' in window)
     ws = new mozwebsocket("ws://localhost:/websocket/mywebsocket.do");
   else
     alert("not support");
   ws.onmessage = function(evt) {
     //alert(evt.data);
     console.log(evt);
     $("#xiaoxi").val(evt.data);
   };
   ws.onclose = function(evt) {
     //alert("close");
     document.getelementbyid('denglu').innerhtml="离线";
   };
   ws.onopen = function(evt) {
     //alert("open");
     document.getelementbyid('denglu').innerhtml="在线";
     document.getelementbyid('username').innerhtml='小化';
   };
 }
 function sendmsg() {
   var fromname = "小化";
   var toname = document.getelementbyid('name').value; //发给谁
   var content = document.getelementbyid('writemsg').value; //发送内容
   ws.send(fromname+","+toname+","+content);
 }
 </script>
 </head>
 <body onload="startwebsocket();">
 <p>聊天功能实现</p>
 登录状态：
 <span id="denglu" style="color:red;">正在登录</span>
 <br>
 登录人：
 <span id="username"></span>
 <br>
 <br>
 <br>
 发送给谁：<input type="text" id="name" value="小明"></input>
 <br>
 发送内容：<input type="text" id="writemsg"></input>
 <br>
 聊天框：<textarea rows="" cols="" readonly id="xiaoxi"></textarea>
 <br>
 <input type="button" value="send" onclick="sendmsg()"></input>
 </body>
 </html>

 b.小明

<%@ page language="java" contenttype="text/html; charset=utf-8"
  pageencoding="utf-8"%>
<!doctype html>
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=utf-8">
<title>index</title>
<script type="text/javascript" src="js/jquery 2.1.1.min.js"></script>
<%session.setattribute("user", "小明");%>
<script type="text/javascript">
var ws = null;
function startwebsocket() {
  if ('websocket' in window)
    ws = new websocket("ws://localhost:8080/websocket/mywebsocket.do");
  else if ('mozwebsocket' in window)
    ws = new mozwebsocket("ws://localhost:8080/websocket/mywebsocket.do");
  else
    alert("not support");
  ws.onmessage = function(evt) {
    console.log(evt);
    //alert(evt.data);
    $("#xiaoxi").val(evt.data);
  };
  ws.onclose = function(evt) {
    //alert("close");
    document.getelementbyid('denglu').innerhtml="离线";
  };
  ws.onopen = function(evt) {
    //alert("open");
    document.getelementbyid('denglu').innerhtml="在线";
    document.getelementbyid('username').innerhtml="小明";
  };
}
function sendmsg() {
  var fromname = "小明";
  var toname = document.getelementbyid('name').value; //发给谁
  var content = document.getelementbyid('writemsg').value; //发送内容
  ws.send(fromname+","+toname+","+content);
}
</script>
</head>
<body onload="startwebsocket();">
<p>聊天功能实现</p>
登录状态：
<span id="denglu" style="color:red;">正在登录</span>
<br>
登录人：
<span id="username"></span>
<br>
<br>
<br>
发送给谁：<input type="text" id="name" value="小化"></input>
<br>
发送内容：<input type="text" id="writemsg"></input>
<br>
聊天框：<textarea rows="13" cols="100" readonly id="xiaoxi"></textarea>
<br>
<input type="button" value="send" onclick="sendmsg()"></input>
</body>
</html>

以上所述是小编给大家介绍的使用javaweb websocket实现简易的点对点聊天功能实例代码的相关知识，希望对大家有所帮助