GWT exception : Deferred binding result type should not be abstract Or Rebind result must be a class

In GWT, when you get this error in hosted mode
Deferred binding result type should not be abstract
or
The following error while compiling
Rebind result must be a class

most likely you have forgot to extend your business interface from RemoteService. Therefore GWT engine is trying to instantiate the interface itself. That is , instead of

@RemoteServiceRelativePath("relativeServicePath")
    public interface BusinessInterface extends RemoteService

you have written

@RemoteServiceRelativePath("relativeServicePath")
    public interface BusinessInterface