public int hashCode(){
  int hashCode=this.hashCode;
  if (hashCode == 0) {
    hashCode=((groupId.hashCode() * 19 + artifactId.hashCode()) * 19 + version.hashCode()) * 19 + classifier.hashCode();
    if (hashCode == 0) {
      hashCode=-1;
    }
    this.hashCode=hashCode;
  }
  return hashCode;
}

public int hashCode ( ) { int hashCode = this . hashCode ; if ( hashCode == 0 ) { hashCode = ( ( groupId . hashCode ( ) * 19 + artifactId . hashCode ( ) ) * 19 + version . hashCode ( ) ) * 19 + classifier . hashCode ( ) ; if ( hashCode == 0 ) { hashCode = - 1 ; } this . hashCode = hashCode ; } return hashCode ; }
get the hash code .
