[Geoserver-devel] after deploy own service ,get execption

sir , i want run sample code which is inside developer mannual but after deploy jar file in E:\GeoServer2.4.5\webapps\geoserver\WEB-INF\lib , i got exception like:------------------------------------------

org.geoserver.platform.ServiceException: No service: ( hello )
at org.geoserver.ows.Dispatcher.service(Dispatcher.java:518)
at org.geoserver.ows.Dispatcher.handleRequestInternal(Dispatcher.java:250)
at etty.bio.SocketConnector$Connection.run(SocketConnector.java:228)
at org.mortbay.thread.BoundedThreadPool$PoolThread.run(BoundedThreadPool.java:450)

sir, please give me solution…