COLLECTIONS-604

[Kaammill]

Hi,
I was thinking about the more uniform safe-null methods in CollectionUtils from jira task: COLLECTIONS-604. In my opinion it would be nice to have one way of treating null-safe methods. I decided to try wit the approach that the methods that already return Boolean values could be null-save. I would appreciate all kind of feedback on this task :)

[Simulant87]

The code below will still throw a now no longer documented and expected NullPointerException if coll1 if not null but coll2 is null.
It's the same thing for the change in the method below, and possible more, I haven't read through the whole PR.

[Claudenw]

I think you need to think about set operations.

what does containsAny(x,y) mean if

• y is null? If this is a set operation then all X contain the null set.
• x is null? If this is a set operation then the null set does not contain any other set, except perhaps the null set.

I think the same questions need to be answered for all the collections questions.

I would recommend updating the javadoc for each method so that it is clear what the various null values return.

[Claudenw]

@Kaammill The more I think about this change the more I think that there is a significant issue.
Changing the code to not throw an NPE when the NPE was documented in the earlier release is (I think) a breaking change and would require a new major version.

Alternatively, a new set of classes that handle Null pointer arguments differently might be valuable. However, this is a discussion to have on the dev mailing list.

Are you still interested in making these changes?

[garydgregory]

Closing: No reply from OP in over a year.