question: @ Override public int hashCode ( ) { int result ; long temp ; temp = Double . doubleToLongBits ( this . x1 ) ; result = ( int ) ( temp ^ ( temp > > > 32 ) ) ; temp = Double . doubleToLongBits ( this . x2 ) ; result = 29 * result + ( int ) ( temp ^ ( temp > > > 32 ) ) ; temp = Double . doubleToLongBits ( this . y1 ) ; result = 29 * result + ( int ) ( temp ^ ( temp > > > 32 ) ) ; temp = Double . doubleToLongBits ( this . y2 ) ; result = 29 * result + ( int ) ( temp ^ ( temp > > > 32 ) ) ; return result ; }
target:  Returns a hash code.