On 13 May 2014, at 3:47 PM, David Astels <dast...@icloud.com> wrote: > Well, an issue of good OO design or not. Returning a mutable collection > breaks encapsulation. My initial question is whether the collection is simply > a detail of the implementation or part of the external interface you want to > expose. If the former, hide the collection and expose operations that provide > what’s truly needed. If the latter, then you might need immutable > collections.
Agree 100% with David’s comment, it’s an issue of good OO design and there are valid cases to return immutable collections. I think most developers return internal collections, breaking encapsulation, but get away with it 99% of the time and only occasionally get burnt with a nasty bug or a deep mess. Cheers Carlo
