1:把dwr.jar放到项目下的\WebRoot\WEB-INF\lib

2:在web.xml中写入
<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>
    <init-param>
     <param-name>classes</param-name>
     <param-value>java.lang.Object</param-value>
    </init-param>
    <init-param>
     <param-name>scriptSessionTimeout</param-name>
     <param-value>3600000</param-value>
    </init-param>
    <init-param>
     <param-name>maxCallCount</param-name>
     <param-value>20</param-value>
    </init-param>
    <init-param>
     <param-name>pollAndCometEnabled</param-name>
     <param-value>true</param-value>
    </init-param>
    <init-param>
     <param-name>logLevel</param-name>
     <param-value>DEBUG</param-value>
 </init-param>
  </servlet>
  <servlet-mapping>   
    <servlet-name>dwr-invoker</servlet-name>
 <url-pattern>/dwr/*</url-pattern>
  </servlet-mapping>
3:建立一个DwrLx.java文件 在里面建立一个方法YZDwr()
4:在WebRoot/WEB-INF/中加入dwr.xml文件(每新写一个类就在里面配置一下)
   文件内容为:

<?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="Dwr"> //在jsp 中调用的名字
     <param name="class" value="com.dwr.DwrLx" />///要调用的类路径
    </create>
/////////如果要用bean就要配置下面的
    <!--<convert converter="bean" match="com.dwr.User">///////// 使用的哪个bean
    <param name="include" value="userid,username" /> //////返回bean中要用到的哪个属性
   </convert>--->
  </allow>
</dwr>
5:jsp 中写入
<script type='text/javascript' src='/项目名/dwr/engine.js'></script>
 <script type='text/javascript' src='/项目名/dwr/interface/Dwr.js'></script>

    <script type="text/javascript">
    function map()
  {
    DwrLx.YZDwr('sdfsdf',backMap);///传递参数必须上字符串,int不认识backMap调用的返回函数
  }

  function backMap(beans)
  {
 ///返回map直接map.key; 
alert(beans.ee)   
////返回list
for(var i=0;i<beans.length;i++)
{
 alert( beans[i].ee);
}
//////返回beans
alert(beans.userid+"********"+beans.username);
  }
 </script>