Custom controllers, resource paths and PluginDescriptor

In the Obtaining paths to JSP files section of Web UI Extensions, it reads:

However to construct paths to your JSP or images in Java it is recommended to use jetbrains.buildServer.web.openapi.PluginDescriptor

But I can't find a bean that implements that interface. Anyone know what the bean's name is?

Thanks

Ben

[EDIT] What about WebUtil, is that useful?

Message was edited by: Ben