Collection is the primary collection interface for mutable collections

Assuming you want the ability to clear out your collection, you would implement this (or a child of this) interface. Otherwise, you can implement OutputCollection only. If your collection to be immutable, implement ConstCollection only instead.

Interface Synopsis

namespace HH {
interface Collection implements ConstCollection, OutputCollection,                                  OutputCollection {...}
  • ->clear()
    Removes all items from the collection