HashSet with two equals object?

Question

I created an object HashSet, and the value is an object (Triple) which is my own class. But I get a strange thing, when there are two equal objects on my HashSet, is it poss

Answer 1

You need to be sure to implement hashCode() as well, and when two Triples are equal, their hashCodes must also be equal. If you don't do that, you will get strange behavior.