ajax 开源项目 DWR

源哥

发布于 2019-05-26 17:27:59

7740

发布于 2019-05-26 17:27:59

文章被收录于专栏：源哥的专栏

ajax 开源项目 DWR

ajax开源项目dwr的使用：利用DWR可以在客户端利用JavaScript直接调用服务端的Java方法并返回值给JavaScript就好像直接本地客户端调用一样.

1：下载dwr.jar文件，将其加入到web工程的lib下； 2：在web.xml文件中配置如下信息： <servlet> <servlet-name>dwr-invoker</servlet-name> <servlet-class>uk.ltd.getahead.dwr.DWRServlet</servlet-class> </servlet> <servlet-mapping> <servlet-name>dwr-invoker</servlet-name> <url-pattern>/dwr/*</url-pattern> </servlet-mapping> 其中url-pattern中必须配置为 “/dwr/* ”，不能为工程的名称！！ 3：在web.xml同级中增加文件dwr.xml，此文件是javaScript中调用的方法，影射到class类例如： <!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="MyTest" scope="application"> <param name="class" value="com.test.ajax.DWRTest"/> </create> <create scope="application" creator="new" javascript="showData"> <param name="class" value="com.test.ajax.HelloName"/> </create> </allow> </dwr> 在allow节点中定义要影射的class类，并且给其class类起一个javaScript的名字，以便在 javaScript中调用。 4：然后定义class文件 package com.test.ajax; public class DWRTest { public DWRTest(){ } public String getMyName(){ return "hello_ajax"; } } /** *--------------------------------------------------- **/ package com.test.ajax; public class HelloName { private String userName ; public HelloName(){ } /** * @return Returns the userName. */ public String getUserName() { return "helloTest"; } /** * @param userName The userName to set. */ public void setUserName(String userName) { this.userName = userName; } } 5: 这时就可以在html或jsp中调用此class文件了，调用方式如下一下为测试的 html文件 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <title>DWR - My First AJAX</title> <meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <script type='text/javascript' src='dwr/interface/MyTest.js'></script> <script type='text/javascript' src='dwr/interface/showData.js'></script> <script type='text/javascript' src='dwr/engine.js'></script> <script type='text/javascript' src='dwr/util.js'></script> <script language="javascript"> var mycall=function callBack(data){ DWRUtil.setValue("demo1",data); DWRUtil.setValue("demo2","leo_wang"); DWRUtil.setValue("userName",data); } function showMyName(){ //MyTest.getMyName(mycall); showData.getUserName(mycall); } function clearName(){ demo1.value=""; demo2.value=""; } </script> </head> <body> <h1>Ajax Test Page</h1> <input type="button" value="setMyName" onclick="javascript:showMyName()"> <input type="button" value="Clear" onclick="javascript:clearName()"><br> <input type="text" id="demo1"> <input type="text" id="demo2"> <input type="test" id="userName">userName </body></html> 在调用javaScript前要先引入刚才在dwr.xml中定义的javaScript <script type='text/javascript' src='dwr/interface/MyTest.js'></script> <script type='text/javascript' src='dwr/interface/showData.js'></script> <script type='text/javascript' src='dwr/engine.js'></script> <script type='text/javascript' src='dwr/util.js'></script> 前面两行是我们刚才定义的javaScript的引入，后面两行是dwr中的本身定义的javaScript (heishanlaoyao)