Joshua Bloch PDF On slide 20:
Don't confuse bounded wildcards with bounded type variables.
Bounded wildcards
void sell(Collection<? extends T> myLot);
- Major use: restrict input parameters
- Can use super
Bounded type variables
<T extends Number> T sum(List<T> x) { � }
- Restricts actual type parameter: Works for parameterized classes and methods
- Can't use super
What does he mean when he writes
Can use super and
Can't use super ?
My guess below; but I require your confirmation:
"Can use super" means that I can call #sell( Collection<T> c )."Can't use super" means that #sum( List<Number> ) is disallowed Am I correct ?
[ January 15, 2008: Message edited by: Pho Tek ]