TreeSet Linker

Question

I used TreeSet with a self-recording comparator. Now, when I add elements to the TreeSet and the Comparator comparison methods return 0, it looks like the TreeSet contains only one of the Object with equal rank.

I have not seen this behavior described in javadocs. Maybe I missed something. Can you confirm this behavior?

I edited the comparator. Now it never returns 0, and the TreeSet contains all objects with equal rank.

Is this the way it should be if I want to have multiple objects with equal rank?

Answer 1

This is how it should be, since a collection is defined as including equal objects only once.

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Answer 2

, JavaDoc TreeSet:

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Answer 3

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