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wildcard extends problem Question to supermammoth, why it not works?:
"static void processPair(B b1, B b2, BiConsumer<? extends B, ? extends B> consumer) {
consumer.accept(b1, b2);
}"
but it works?:
"List<? extends B> lb = new ArrayList<B>();
List<? super B> lc = new ArrayList<B>();"
I dont understand wildcard logic in class and methods? Why B is extends of B in one place, but not another? Why it wroks normally for super in both cases?
In common case,
is B extends B?
is B super B?
Re: wildcard extends problem Try asking this question on this forum: http://www.coderanch.com/forums
Now posted here: https://coderanch.com/t/805376/java/wildcard-extends
If you don't understand my answer, don't ignore it, ask a question.
Re: wildcard extends problem Helpful answer from another forum. "Because you could call it: processPair(B, B, BiConsumer<C, C>); And B cannot be passed to BiConsumer<C, C>."
Task done.
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