How to apply complex generic method to class with wildcard generic type?

Question

There are something like:

<T> Identifier<Set<T>> myMethod(Iterable<? extends Element<Identifier<T>>> input) {…}

class MyClass implements Element<Identifier<?>> {…}

Iterable<MyClass> a = …;

How could I pass a to myMethod to get Identifier<Set<?>>?

If you can, you should avoid using a wildcard in an implements clause. — SpaceTrucker, Sep 23 '14 at 11:21
@AlexR `error: method myMethod in class … cannot be applied to given types;` — Timofey Gorshkov, Sep 23 '14 at 11:37

score 1 · Accepted Answer · answered Sep 23 '14 at 11:18

1

Simply blabla.myMethod((Iterable) a);

More specifically:

Identifier<Set<?>> setIdentifier = blabla.myMethod((Iterable) a);

answered Sep 23 '14 at 11:18

Andremoniy

score 0 · Answer 2 · edited May 23 '17 at 12:21

If you have control over myMethod, make its signature more flexible:

<T> Identifier<Set<T>> myMethod(Iterable<? extends Element<Identifier<? extends T>>> input)

And while that's enough to solve your issue, this would be the most flexible:

<T> Identifier<Set<T>> myMethod(Iterable<? extends Element<? extends Identifier<? extends T>>> input)

2 Answers2