There are one or two places where method parameters of type Class will now
be more specific, for example

     public DragGestureRecognizer createDragGestureRecognizer(
        Class<? extends MyDragGestureRecognizer> abstractRecognizerClass, ...

And Class.forName() now returns Class<?>.

In -source 1.5, this can break a client that uses

    dgr.createDragGestureRecognizer(Class.forName("MyDragGestureRecognizer"));

and yet the programmer has no way to generify the client soundly. How
should clients adjust their code? Adding a cast (in this case to
Class<? extends DragGestureRecognizer>) provokes an unchecked warning,
and there is no way to get rid of it. Given that some API designers
will want to create factory-like typesafe APIs in which clients will use
Class.forName(), there needs to be a way for clients to use the API
safely. I suggest adding the following method to class Class:

  class Class<T> { ...

    public <U> Class<? extends U> asSubclass(Class<U> clazz) {
      if (clazz.isAssignableFrom(this))
        return (Class<? extends U>) this;
      else
        throw new ClassCastException(this);
    }
  }