dwr 前台调用后台的java类 hello
dwr 前台调用后台的java类? hello
web项目,service? tomcat
第一部：在web.xml中引入dwr类库
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
? <display-name>dwr_test</display-name>
?
?
? <servlet>
? <display-name>DWR Servlet</display-name>
? <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>
?
?
?
? <welcome-file-list>
??? <welcome-file>index.html</welcome-file>
??? <welcome-file>index.htm</welcome-file>
??? <welcome-file>index.jsp</welcome-file>
??? <welcome-file>default.html</welcome-file>
??? <welcome-file>default.htm</welcome-file>
??? <welcome-file>default.jsp</welcome-file>
? </welcome-file-list>
</web-app>
第二部：准备后台java类供前台调用
Demo.java
package org.getahead.dwrdemo.simpletext;
public class Demo {
public String sayHello(String name) {
return "Hello, " + name;
}
}
第三步：在WEB-INF/下加入文件dwr.xml与web.xml同级目录
dwr.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 3.0//EN" "http://getahead.org/dwr/dwr30.dtd">
<dwr>
? <allow>
??? <create creator="new" javascript="Demo">
????? <param name="class" value="org.getahead.dwrdemo.simpletext.Demo"/>
??? </create>
? </allow>
</dwr>
第四步，前台js调用
<%@ page language="java" contentType="text/html; charset=UTF-8"
??? pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Insert title here</title>
</head>
《！--引入dwr工程? 必须要--》
<script src='/dwr_test/dwr/engine.js'></script>??
《！--引入dwr? 工具类库，需要用时才，引入，不是必须要--》
<script type='text/javascript' src='/dwr_test/dwr/util.js'></script>
《！--dwr配的java类，dwr自动生成一个可以调用java类的js，必需要引入此类--》
<script src='/dwr_test/dwr/interface/Demo.js'></script>
<script>
function update() {
? var name = dwr.util.getValue("demoName");
? Demo.sayHello(name, function(data) {
??? dwr.util.setValue("demoReply", data);
? });
}
</script>
<body>
<p>
? Name:
? <input type="text" id="demoName"/>
? <input value="Send" type="button" onclick="update()"/>
? <br/>
? Reply: <span id="demoReply"></span>
</p>
</body>
</html>
?
