About Java--dwr

"Define DWR":

DWR (Direct Web Remoting) is a remote server-side AJAX open-source framework for improving WEB pages to interact with Java classes.DWRtook a similarAJAXa new way to dynamically generateJAVAClass ofJavaScriptCode.thisWEBdevelopers will be able toJavaScriptused inJavacode as if they were local code of the browser(Client Code)same;butJavacode runs onWEBserver-side and free to accessWEBresources for the server.For reasons of safety, the WEBdevelopers have to properly configure whichJavaclasses can be safely used externally.

It consists of two main parts:

1. Allow JavaScript to get data from a servlet in the Web server that adheres to the Ajax principles.

2, JS Library can help developers to successfully use the data obtained to dynamically change the content of the Web page.

"Using DWR"

1, first must have the DWR jar package file: (Provide download path: Dwrjar file download)

2. Configure Dwr in Web. xml:

<!--configuring DWR--><servlet><servlet-name>dwr-invoker</servlet-name><servlet-class> org.directwebremoting.servlet.dwrservlet</servlet-class></servlet><servlet-mapping>< servlet-name>dwr-invoker</servlet-name><url-pattern>/dwr/*</url-pattern></ Servlet-mapping>

3. Create the class Adjbudgetmodel, and then create the method you want in the class:

/** * Used on the tree above the action by Xihy handling the dynamic processing of the interface event 2010-05-11 */public adjbudgetplaninfo gainthebootinfo (String bootid) throws Excepti on{/** * Query root node record */try{return treebugetdao.gainthebootinfo (bootid);} catch (Exception e) {e.printstacktrace (); return null;}}

4. adjbudgetplaninfo file

Package Com.xx.xx.budget.domain;public class Adjbudgetplaninfo {private String   bpiid                   ;p rivate string   Bctid                   ;p rivate string   bacid                   ;p rivate string   depid                   ;}        **ps: Here shorthand, there are some fields are not written out, and the corresponding set and get are not written out, here is just shorthand, then you can according to the needs of their own projects to improve

4. Create the Dwr.xml file and configure the class you just createdAdjbudgetmodel

<?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> <create creator= "Spring" javascript= "Adjbudgetserver" >                <param name= " Beanname "    value=" Adjbudgetmodel "/>        </create>

<!--returns him as an object to the client---        <convert match= "com.xx.xx.budget.domain.AdjBudgetPlanInfo" converter= "Bean" >       <param name= "include" value= "bpiid,bpiname,bpiisroot,haschildren,bpicreatedate,bpscid,bacid,proid, Bpilevel "></param>    </convert>      <convert match=" java.lang.Exception "converter=" Exception ">    <param name= ' include ' value= ' message '/>    </convert></allow></dwr>

5. Use in JSP pages

First introduced on your JSP page, the name introduced is the one that was configured in the XML file just now.

{PS: Here we are only responsible for the introduction, here is DWR introduced through the reflection mechanism.}

Then there is the use on the page:

function Startt () {<%if (null! = value &&!value.equals ("")) {%>adjbudgetserver.gainthebootinfo (' <%= Value%> ', {exceptionhandler:function (msg) {alert (msg);},callback:showsub}); <%}else{%>alert (' xxx '); <% }%>}

：
: The above is what I used in the project

About Java--dwr