用http://localhost:8080/HelloWorldTest/dwr访问，结果浏览器上面没有看到自己发布的类？

用http://localhost:8080/HelloWorldTest/dwr访问，结果浏览器上面没有看到自己发布的类？只有这个：
Classes known to DWR:Other Links    Up to top level of web app.
（没有看到自己发布的类）
正在学dwr，问题如题，犯的错误是这个：
警告: Error setting class=helloWorld.Service on uk.ltd.getahead.dwr.create.NewCreator
java.lang.IllegalArgumentException: Class not found: helloWorld.Service
at uk.ltd.getahead.dwr.create.NewCreator.setClass(NewCreator.java:39)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at uk.ltd.getahead.dwr.util.LocalUtil.setProperty(LocalUtil.java:281)
at uk.ltd.getahead.dwr.impl.DefaultCreatorManager.addCreator(DefaultCreatorManager.java:105)
at uk.ltd.getahead.dwr.impl.DefaultConfiguration.loadCreate(DefaultConfiguration.java:255)
at uk.ltd.getahead.dwr.impl.DefaultConfiguration.loadAllows(DefaultConfiguration.java:196)
at uk.ltd.getahead.dwr.impl.DefaultConfiguration.addConfig(DefaultConfiguration.java:90)
at uk.ltd.getahead.dwr.impl.DefaultConfiguration.addConfig(DefaultConfiguration.java:66)
at uk.ltd.getahead.dwr.AbstractDWRServlet.readFile(AbstractDWRServlet.java:188)
at uk.ltd.getahead.dwr.DWRServlet.configure(DWRServlet.java:117)
at uk.ltd.getahead.dwr.AbstractDWRServlet.init(AbstractDWRServlet.java:119)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1173)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:809)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:129)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:859)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Unknown Source)Service.java,web.xml,dwr.xml代码如下：
--------------------------------------
package helloWorld;public class Service {
public String sayHello(String yourName){
return "Hello World"+yourName;
}
}
--------------------------------------
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<servlet-name>dwr-invoker</servlet-name>
<servlet-class>
uk.ltd.getahead.dwr.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.jsp</welcome-file>
</welcome-file-list>
</web-app>
----------------------------------------------------
dwr.xml
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE dwr PUBLIC "-//GetAhead Limited//DTD Direct Web Remoting 1.0//EN" "http://www.getahead.ltd.uk/dwr/dwr10.dtd">
<dwr>
<allow>
<create creator="new" javascript="service">
<param name="class" value="helloWorld.Service" />
</create>
</allow>
</dwr>