Hashcode and equals

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Equality is only determined by method equals(). And method hashCode() is used in other situations, like by Map or Set. It is somewhat like a pre-condition or hint before actually calling equals (for efficiency). So it is assumed that if 2 objects are equal (that is, equals() returns true), then their hashCodes() must return the same value.

So in your code, 2 objects are equal, as long as your overriden equals() returns true, no matter what hashCode() does. hashCode() is not called at all when comparing for equality.

This question has more in-depth information regarding to the relationship between equals() and hashCode().

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