Some SA classes could use better hashCode() implementation

    public int hashCode() {
        // FIXME: suggestions on a better hash code?
        return (int) addr;
    }

The upper 32-bits of the addr long value could be used in the hash code calculation. Long.hashCode(long value) can be used to accomplish this:

     (int)(this.longValue()^(this.longValue()>>>32))