question: @ Override public void append ( ResultEntry entry ) { qualityIndicator . calculate ( entry . getPopulation ( ) ) ; writer . print ( qualityIndicator . getHypervolume ( ) ) ; writer . print ( ' ' ) ; writer . print ( qualityIndicator . getGenerationalDistance ( ) ) ; writer . print ( ' ' ) ; writer . print ( qualityIndicator . getInvertedGenerationalDistance ( ) ) ; writer . print ( ' ' ) ; writer . print ( qualityIndicator . getSpacing ( ) ) ; writer . print ( ' ' ) ; writer . print ( qualityIndicator . getAdditiveEpsilonIndicator ( ) ) ; writer . print ( ' ' ) ; writer . print ( qualityIndicator . getMaximumParetoFrontError ( ) ) ; writer . println ( ) ; numberOfEntries ++ ; }
target:  Evaluates the specified non-dominated population and outputs the resulting metrics to the file.