I wanted to model a very simple class diagram with NetBeans UML that uses some features of Java generics. I used the 
following steps:
1) create an interface with a template parameter
2) add a method that uses the template parameter
3) create a derivation of the interface
4) add another class that implements the derived interface

To my surprise, the class redefined operations from the interface and not from the derivation. I expected the class to 
redefine something like:
   public void doSomething(String input)
but it redefined
   public void doSomething(T input)

I will attach a screenshot...