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Author : Paul Hamaker. Part of

To join two entire collections, we can use one of the so called 'bulk operations'.

To check if another collection is a subset.

To distill the intersection.

And how to determine the set difference.

All of these bulk operations can be applied to Sets and Lists. Maps only have a putAll method, to add another Map, but you can perform bulk operations via the keySet, entrySet and values methods. Excepting addAll, however.