CODEWITHSUNDEEP
javahashmapiteratorset
WebNerdy
WebNerdy

Reputation: 11

Is Iterator method only for Set in Collection Framework?

I was studying framework and I saw an example which is transferring from HashMap to Set like Set set = map.entrySet(); then Iterator it = set.iterator(); for using Iterator method for access each key set.

From that, I'm confused that is Iterator method only for Set in Collection framework?

Upvotes: 1

Views: 45

Answers (1)

user13784117
user13784117

Reputation: 1132

Iterator<> is an interface, as is Collection<>.

An implementation of Collection is required to be iterable. It will provide an implementation of Iterator that is specialized to iterate over that collection type, and a method to return an instance of that iterator.

So, if I implement class PileOfStuff implements Collection<Stuff>, somewhere behind the scenes I'll have something like class PileOfStuffIterator implements Iterator<Stuff> and PileOfStuff.iterator() will return such an iterator.

Upvotes: 1

Related Questions