org.apache.commons.collections.comparators

Class TransformingComparator

java.lang.Object

org.apache.commons.collections.comparators.TransformingComparator

All Implemented Interfaces:

java.util.Comparator

public class TransformingComparator
extends java.lang.Object
implements java.util.Comparator

Decorates another Comparator with transformation behavior. That is, the return value from the transform operation will be passed to the decorated compare method.

Since:

Commons Collections 2.0 (?)

See Also:

Transformer, ComparableComparator

Constructor Summary

Constructors

Constructor and Description
TransformingComparator(Transformer transformer) Constructs an instance with the given Transformer and a ComparableComparator.
TransformingComparator(Transformer transformer, java.util.Comparator decorated) Constructs an instance with the given Transformer and Comparator.

Method Summary

Modifier and Type	Method and Description
int	compare(java.lang.Object obj1, java.lang.Object obj2) Returns the result of comparing the values from the transform operation.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Constructor Detail

TransformingComparator

public TransformingComparator(Transformer transformer)

Constructs an instance with the given Transformer and a ComparableComparator.

Parameters:

transformer - what will transform the arguments to compare

TransformingComparator

public TransformingComparator(Transformer transformer,
                              java.util.Comparator decorated)

Constructs an instance with the given Transformer and Comparator.

Parameters:

transformer - what will transform the arguments to compare

decorated - the decorated Comparator

Method Detail

compare

public int compare(java.lang.Object obj1,
                   java.lang.Object obj2)

Returns the result of comparing the values from the transform operation.

Specified by:

compare in interface java.util.Comparator

Parameters:

obj1 - the first object to transform then compare

obj2 - the second object to transform then compare

Returns:

negative if obj1 is less, positive if greater, zero if equal