Package org.moeaframework.core.comparator

Class ChainedComparator

java.lang.Object

org.moeaframework.core.comparator.ChainedComparator

All Implemented Interfaces:

DominanceComparator

Direct Known Subclasses:

LinearDominanceComparator, MinMaxDominanceComparator, NondominatedSortingComparator, ParetoDominanceComparator

public class ChainedComparator
extends Object
implements DominanceComparator

Applies any number of comparators in succession, returning the result from the first comparator producing a non-zero return value. If no comparators produce a non-zero return value, 0 is returned.

For example, the following:

   Comparator comparator = new ChainedComparator(comparator1, comparator2);
   return comparator.compare(s1, s2);
 

is equivalent to

   int flag1 = comparator1.compare(s1, s2);
   if (flag1 == 0) {
     return comparator2.compare(s1, s2);
   } else {
     return flag1;
   }
 

Field Summary

Fields

Modifier and Type	Field	Description
protected DominanceComparator[]	comparators	The comparators in the order they are to be applied.

Constructor Summary

Constructors

Constructor	Description
ChainedComparator(DominanceComparator... comparators)	Constructs a chained comparator for applying the specified comparators in order, returning the result from the first comparator producing a non-zero return value.

Method Summary

Modifier and Type	Method	Description
int	compare(Solution solution1, Solution solution2)	Compares the two solutions using a dominance relation, returning -1 if solution1 dominates solution2, 1 if solution2 dominates solution1, and 0 if the solutions are non-dominated.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

comparators

protected DominanceComparator[] comparators

The comparators in the order they are to be applied.

Constructor Details

ChainedComparator

public ChainedComparator(DominanceComparator... comparators)

Constructs a chained comparator for applying the specified comparators in order, returning the result from the first comparator producing a non-zero return value. If no comparators produce a non-zero return value, 0 is returned.

Parameters:

comparators - the comparators in the order they are to be applied

Method Details

compare

public int compare(Solution solution1,
 Solution solution2)

Description copied from interface: DominanceComparator

Compares the two solutions using a dominance relation, returning -1 if solution1 dominates solution2, 1 if solution2 dominates solution1, and 0 if the solutions are non-dominated.

Specified by:

compare in interface DominanceComparator

Parameters:

solution1 - the first solution

solution2 - the second solution

Returns:

-1 if solution1 dominates solution2, 1 if solution2 dominates solution1, and 0 if the solutions are non-dominated