Hashing in Java

Question

I have a Long and a String . I want to create a hash of both of those object. Meaning, I want some function that will take arbitrary number of objects and return me one hash value. Does such a function exits?

Something like this:

public int getHash(Object... objects)
{
     //somehow returns a hash of all these objects
}

Answer 1

Take a look at Arrays.hashCode(Object[]) .

It doesn't accept varargs, but you can wrap it with your own varargs library function if you wish:

public static int computeHashCode(Object... objects) {
   return Arrays.hashCode(objects);
}

Answer 2

The Apache Commons HashCodeBuilder has a reflection-based invocation that is similar to what you want.

public int hashCode() {
    return HashCodeBuilder.reflectionHashCode(this);
}