I’ve used a similar solution to what he explains here for a few projects and found it pretty useful.
http://blog.xebia.com/2009/02/07/acessing-generic-types-at-runtime-in-java/
The jist of it is using the following:
public Class returnedClass() {
ParameterizedType parameterizedType = (ParameterizedType)getClass()
.getGenericSuperclass();
return (Class) parameterizedType.getActualTypeArguments()[0];
}