Just came across a place where I'd like to use generics and I'm not sure how to make it work the way I want.

I have a method in my data layer that does a query and returns a list of objects. Here's the signature.

public List getList(Class cls, Map query)

This is what I'd like the calling code to look like.

List<Whatever> list = getList(WhateverImpl.class, query);

I'd like to make it so that I don't have to cast this to a List coming out, which leads me to this.

public <T> List<T> getList(Class<T> cls, Map query)

But now I have the problem that what I get out is always the concrete List<WhateverImpl> passed in whereas I'd like it to be the Whatever interface. I tried to use the super keyword but couldn't figure it out. Any generics gurus out there know how this can be done?