Objects.hash() vs Objects.hashCode(), clarification needed

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See the documentation for hashCode and hash. hash takes Object... while hashCode takes Object. The example given is:

@Override public int hashCode() {
    return Objects.hash(x, y, z);
}
  • Objects.hash(Object... values) should be used in cases when you want a hash of a sequence of objects, e.g. when defining your own hashCode method and want a simply-coded hash for multiple values that make up the identity of your object.
  • Objects.hashCode(Object o) should be used when you want the hash of a single object, without throwing if the object is null.
  • Object::hashCode() should be used when you want the hash of a single object, and will throw an exception if the object is null.

Note that hash(o) and hashCode(o) won’t necessarily return the same thing! If you’re doing it for a single object, you should probably use hashCode.

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