这期内容当中小编将会给大家带来有关怎么在HTML5中利用WebSocket实现点对点聊天，文章内容丰富且以专业的角度为大家分析和叙述，阅读完这篇文章希望大家可以有所收获。
首先在系统启动的时候调用InitServlet方法
public class InitServlet extends HttpServlet { private static final long serialVersionUID = -3163557381361759907L; private static HashMap<String,MessageInbound> socketList; public void init(ServletConfig config) throws ServletException { InitServlet.socketList = new HashMap<String,MessageInbound>(); super.init(config); System.out.println("初始化聊天容器"); } public static HashMap<String,MessageInbound> getSocketList() { return InitServlet.socketList; } }这里你可以跟自己的系统结合，对应的web配置代码如下：
<?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>websocket</servlet-name> <servlet-class>socket.MyWebSocketServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>websocket</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><!--方法执行的级别--> </servlet> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list></web-app>这就是最普通的前台像后台发送请求的过程，也是很容易嵌入到自己的系统里
MyWebSocketServlet：
public class MyWebSocketServlet extends WebSocketServlet { public String getUser(HttpServletRequest request){ String userName = (String) request.getSession().getAttribute("user"); if(userName==null){ return null; } return userName; } protected StreamInbound createWebSocketInbound(String arg0, HttpServletRequest request) { System.out.println("用户" + request.getSession().getAttribute("user") + "登录"); return new MyMessageInbound(this.getUser(request)); }}MyMessageInbound继承MessageInbound
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 arg0) throws IOException { } @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 MessageInbound messageFromInbound = userMsgMap.get(fromName); if(messageInbound!=null && messageFromInbound!=null){ //如果发往人 存在进行操作 WsOutbound outbound = messageInbound.getWsOutbound(); WsOutbound outFromBound = messageFromInbound.getWsOutbound(); String content = messageMap.get("content"); //获取消息内容 String msgContentString = fromName + "说: " + content; //构造发送的消息 //发出去内容 CharBuffer toMsg = CharBuffer.wrap(msgContentString.toCharArray()); CharBuffer fromMsg = CharBuffer.wrap(msgContentString.toCharArray()); outFromBound.writeTextMessage(fromMsg); outbound.writeTextMessage(toMsg); // outFromBound.flush(); 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);//存放客服ID与用户 } } @Override public int getReadTimeout() { return 0; } }在onTextMessage中处理前台发出的信息，并封装信息传给目标
还有一个messageutil
package util;import java.nio.CharBuffer;import java.util.HashMap;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[0]); map.put("toName", m[1]); map.put("content", m[2]); return map; }}当然了，前台也要按照规定的格式传信息
<%@ 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-1.7.2.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:8080/WebSocketUser/websocket.do"); else if ('MozWebSocket' in window) ws = new MozWebSocket("ws://localhost:8080/WebSocketUser/websocket.do"); else alert("not support"); ws.onmessage = function(evt) { //alert(evt.data); console.log(evt); // $("#xiaoxi").val(evt.data); setMessageInnerHTML(evt.data); }; function setMessageInnerHTML(innerHTML){ document.getElementById('message').innerHTML += innerHTML + '<br/>'; } 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);//注意格式}</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：<div id="message" style="height: 250px;width: 280px;border: 1px solid; overflow: auto;"></div><br><input type="button" value="send" onclick="sendMsg()"></input></body></html>上述就是小编为大家分享的怎么在HTML5中利用WebSocket实现点对点聊天了，如果刚好有类似的疑惑，不妨参照上述分析进行理解。如果想知道更多相关知识，欢迎关注编程网行业资讯频道。
