DWR是很好用的一个Ajax框架闲话不说 如果你找这个技术可定时了解Dwr的
Index页面
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'index.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
<script type='text/javascript' src='/JavaChatDwr/dwr/interface/JavascriptChat.js'></script>
<script type='text/javascript' src='/JavaChatDwr/dwr/engine.js'></script>
<script type='text/javascript' src='/JavaChatDwr/dwr/util.js'></script>
<script type="text/javascript">
function sendMessage(){
//获得用户输入的文本
var test = dwr.util.getValue("text");
//发送信息
JavascriptChat.sendMessage(test);
}
</script>
</head>
<body>
<input type="text" value="" name="" id="text"/>
<input type="button" value="发送" onclick="sendMessage()"/>
</body>
</html>
Show页面
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>My JSP 'show.jsp' starting page</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
<script type='text/javascript'
src='/JavaChatDwr/dwr/interface/JavascriptChat.js'>
</script>
<script type='text/javascript' src='/JavaChatDwr/dwr/engine.js'>
</script>
<script type='text/javascript' src='/JavaChatDwr/dwr/util.js'>
</script>
<script type="text/javascript">
function init() {
//启用Ajax反转
dwr.engine.setActiveReverseAjax(true);
JavascriptChat.inits();
}
window.onload=init;
</script>
</head>
<body>
<div id="div1">
</div>
</body>
</html>
bean类
package com.dragon.dwr;
import java.util.Collection;
import org.directwebremoting.ScriptSession;
import org.directwebremoting.WebContext;
import org.directwebremoting.WebContextFactory;
import org.directwebremoting.proxy.dwr.Util;
public class JavaChat {
//获得WebContext 工厂实例
WebContext wctx = WebContextFactory.get();
/**
* 保存用户打开的页面的session
*/
public void inits(){
wctx = WebContextFactory.get();
//获得当前打开的页面
String currentPage = wctx.getCurrentPage();
//清空对象
//获得打开当前页面的所有的session对象
Collection<ScriptSession> scriptSessions = wctx.getScriptSessionsByPage(currentPage);
}
public void sendMessage(String message){
System.out.println(message);
//获得当前打开的页面
String currentPage = wctx.getCurrentPage();
//清空对象
//获得打开当前页面的所有的session对象
Collection<ScriptSession> scriptSessions = wctx.getScriptSessionsByPage(currentPage);
//创建Dwr的util对象
Util utils = new Util(scriptSessions);
//对id为Div1的标签赋值
utils.setValue("div1", message);
}
}
WEB.XML配置
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
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_2_5.xsd">
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<!-- web中配置Dwr -->
<display-name>DWR (Direct Web Remoting)</display-name>
<description>A Simple Demo DWR</description>
<servlet>
<!-- 指定DWR核心ServletName -->
<servlet-name>dwr-invoker</servlet-name>
<!-- 指定DWR实现类 -->
<servlet-class>org.directwebremoting.servlet.DwrServlet</servlet-class>
<!-- 指定DWR核心Servlet处于调试状态 -->
<init-param>
<param-name>debug</param-name>
<param-value>true</param-value>
</init-param>
<!-- 启用Ajax反转技术 如果删除则不启用 -->
<init-param>
<param-name>activeReverseAjaxEnabled</param-name>
<param-value>true</param-value>
</init-param>
<!-- By default DWR creates application scope objects when they are first
used. This creates them when the app-server is started -->
<init-param>
<param-name>initApplicationScopeCreatorsAtStartup</param-name>
<param-value>true</param-value>
</init-param>
<!-- This enables full streaming mode. It's probably better to leave this
out if you are running across the internet -->
<init-param>
<param-name>maxWaitAfterWrite</param-name>
<param-value>-1</param-value>
</init-param>
<!--
For more information on these parameters, see:
- http://getahead.org/dwr/server/servlet
- http://getahead.org/dwr/reverse-ajax/configuration
-->
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>dwr-invoker</servlet-name>
<url-pattern>/dwr/*</url-pattern>
</servlet-mapping>
</web-app>
dwr.xml配置
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 2.0//EN" "http://getahead.org/dwr/dwr20.dtd">
<dwr>
<allow>
<!--
<filter class="org.getahead.dwrdemo.monitor.MonitoringAjaxFilter"/>
<filter class="org.directwebremoting.filter.ExtraLatencyAjaxFilter">
<param name="delay" value="200"/>
</filter>
-->
<!-- chat -->
<create creator="new" javascript="JavascriptChat" scope="application">
<param name="class" value="com.dragon.dwr.JavaChat"/>
</create>
<!-- 设置类型转换 -->
<convert converter="bean" match="com.dragon.entity.User"/>
<!-- this is a bad idea for live, but can be useful in testing -->
<convert converter="exception" match="java.lang.Exception"/>
<convert converter="bean" match="java.lang.StackTraceElement"/>
</allow>
</dwr>
<wbr></wbr>
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