Is it possible for two objects, considered not equal by equals, to have the same hashCode value?

Yes, it is possible. In Java, the contract of the equals() and hashCode() methods requires that if two objects are equal according to equals(), then they must have the same hashCode(). However, the reverse is not necessarily true: two objects with the same hashCode() may not be equal according to equals().

This is because hashCode() returns an integer value of fixed size, and different objects can have collisions — the same hash.

For example, in collections like HashMap or HashSet, hashCode() is compared first, and then equals() is used for precise equality determination.