I have a vector class with hashCode() implemented. It wasn't written by me, but uses 2 prime numbers by which to multiply the 2 vector components before XORing them. Here it is:

    /*class Vector2f*/
...
    public int hashCode()
    {
        return 997 * ((int)x) ^ 991 * ((int)y); //large primes! 
    }

...As this is from an established Java library, I know that it works just fine.

Then I have a Boundary class, which holds 2 vectors, "start" and "end" (representing the endpoints of a line). The values of these 2 vectors are what characterize the boundary.

    /*class Boundary*/
...
    public int hashCode()
    {
        return 1013 * (start.hashCode()) ^ 1009 * (end.hashCode());
    }

Here I have attempted to create a good hashCode() for the unique 2-tuple of vectors (start & end) constituting this boundary. My question: Is this hashCode() implementation going to work?

(Note that I have used 2 different prime numbers in the latter hashCode() implementation; I don't know if this is necessary but better to be safe than sorry when trying to avoid common factors, I guess -- since I presume this is why primes are popular for hashing functions.)