TA的每日心情 | 开心 2021-3-12 23:18 |
---|
签到天数: 2 天 [LV.1]初来乍到
|
DWR的原理为:把java类注入JS从且达到可以在JS中调用JAVA类中的方法,实现了异步调用。
同GWT相比DWR的优点有
一、DWR可以同JS和HTML同步调用,从且解决GWT中页面美工排版的困难。
二、dwr是把JAVA类注入JS中,而不需要学习新的技术。
web.xml文件配置如下:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<Servlet>
<servlet-name>dwr-invoker</servlet-name>
<servlet-class>
org.directwebremoting.servlet.DwrServlet
</servlet-class>
<init-param>
<param-name>debug</param-name>
<param-value>true</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>dwr-invoker</servlet-name>
<url-pattern>/dwr/*</url-pattern>
</servlet-mapping>
</web-app> dwr文件配置如下: <?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 2.0//EN" "http://www.getahead.ltd.uk/dwr/dwr20.dtd">
<dwr>
<allow>
<create creator="new" javascript="service">
<param name="class" value="cn.epem.admin.Service" />
</create>
</allow>
</dwr> test.jsp <%@ page language="java" pageEncoding="UTF-8"%>
<HTML>
<head>
<title>My JSP "first_dwr.jsp" starting page</title>
<script type="text/javascript" src="<%=request.getContextPath()%>/loadreport.js"></script>
<script type="text/javascript" src="<%=request.getContextPath()%>/dwr/engine.js"></script>
<script type="text/javascript" src="<%=request.getContextPath()%>/dwr/util.js"></script>
<script type="text/javascript" src="<%=request.getContextPath()%>/dwr/interface/service.js"> </script>
</head>
<body>
<input type="button" name="button" value="测试" onclick="firstDwr()">
</body>
</html>
loadreport.js function firstDwr(){
service.sayHello("Jorwen",callBackHello);
}
function callBackHello(data){
alert(data);
}
Service.java package cn.epem.admin; public class Service {
public String sayHello(String yourName) {
System.out.println(yourName);
return "Hello World " + yourName;
}
}
运行图:
源码下载:http://file.javaxxz.com/2014/10/13/015117562.zip |
|