question: protected int hash ( Object key1 , Object key2 , Object key3 ) { int h = 0 ; if ( key1 != null ) { h ^= key1 . hashCode ( ) ; } if ( key2 != null ) { h ^= key2 . hashCode ( ) ; } if ( key3 != null ) { h ^= key3 . hashCode ( ) ; } h += ~ ( h << 9 ) ; h ^= ( h > > > 14 ) ; h += ( h << 4 ) ; h ^= ( h > > > 10 ) ; return h ; }
target:  Gets the hash code for the specified multi-key.