java - Inheritance with generics + collection + method = question -

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i have problem generics , collection. java support generics @ compilation level. can't use case b. 

{     foo(new hashset<i>());  //case     foo(new hashset<c>());  //case b: wrong } void foo(set<i> set){} class c implements i{} interface {}

so how can use function foo set< c > parameter?

thanks.

by changing signature of foo:

void foo(set<? extends i> set){}

you won't able add values set within foo, you'll able iterate on them or check containment.


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