dwr not found 404错误

Question

jsp中导入dwr.xml中的js
<!-- 导入DWR运行时生成的JS工具 --> <script type="text/javascript" src="dwr/engine.js"></script>
<script type="text/javascript" src="dwr/util.js"></script> <!--导入动态生成的js   导入在dwr.xml中配置的 create javascript对应的名字-->
<script type="text/javascript" src="dwr/interface/Hello.js"></script>
<script type="text/javascript" src="dwr/interface/Customer.js"></script>dwr.xml
<?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 javascript="Hello" creator="new">
            <param name="class" value="cn.com.vo.TestDwr"></param>
            <include method="sayHello"/>
            <include method="add"/>
          </create>
          
          <create javascript="Customer" creator="new">
             <param name="class" value="cn.com.vo.Servlet"></param>
          </create>
          
          <!-- dwr只能转基本数据类型 如果传入的是bean 就要通过convert match要转换bean的名字 converter标识是bean-->
          <convert match="cn.com.vo.CustomerVO" converter="bean"></convert>
     </allow>
</dwr>
web.xml
  <servlet>
    <servlet-name>dwr</servlet-name>
    <servlet-class>org.directwebremoting.servlet.DwrServlet</servlet-class>
  </servlet>
  <servlet-mapping>
    <servlet-name>dwr</servlet-name>
    <url-pattern>/dwr/*</url-pattern>
  </servlet-mapping>