Question

Can two equal objects have different hash codes?

Options:

Yes, because the hash code of an object depends on its memory location, which can vary even for equal objects.
No, two equal objects will always have the same hash code by definition.
Yes, it is possible for equal objects to have different hash codes due to variations in the hashing algorithm used.
No, the hash code of an object is solely determined by its internal state, so equal objects must have the same hash code.

Answer 1

Two equal objects must have the same hash code, as their hash codes are dictated by their internal state rather than their memory location or the hashing algorithm.

Step-by-step explanation:

The question at hand is whether two equal objects can have different hash codes. The correct answer is: No, the hash code of an object is solely determined by its internal state, so equal objects must have the same hash code.

According to the general contract of the hashCode method, which is used in languages like Java, when two objects are considered equal according to the equals() method, they must have the same hash code.

This is crucial for the proper functioning of hash-based collections, such as HashSet or HashMap, which rely on the hashCode method to locate objects efficiently.

While the memory location or variations in the hashing algorithm might seem to influence the hash code, it is the object's internal state that dictates its hash code. However, it's worth noting that the opposite is not necessarily true: two objects with the same hash code are not always equal, as hash collisions can occur.