public static int hashCode(final Object obj){
  return (obj == null ? 0 : obj.hashCode());
}

public static int hashCode ( final Object obj ) { return ( obj == null ? 0 : obj . hashCode ( ) ) ; }
a null - safe computation of the specified object ' s hash value . if the object reference is null , then this method returns 0 and will be consistent with the equalsignorenull equality comparison . < p / >
