java.util
Class Collections.ReverseComparator

java.lang.Object
  java.util.Collections.ReverseComparator

All Implemented Interfaces:

Comparator, Serializable

Enclosing class:

Collections

private static class Collections.ReverseComparator

extends Object

implements Comparator, Serializable

See Also:

Serialized Form

Field Summary

private static long

serialVersionUID

Constructor Summary

private

Collections.ReverseComparator()

Method Summary

int	compare(Object o1, Object o2) Compares its two arguments for order.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

equals

Field Detail

serialVersionUID

private static final long serialVersionUID

See Also:

Constant Field Values

Constructor Detail

Collections.ReverseComparator

private Collections.ReverseComparator()

Method Detail

compare

public int compare(Object o1,
                   Object o2)

Description copied from interface: Comparator

Compares its two arguments for order. Returns a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second.

The implementor must ensure that sgn(compare(x, y)) == -sgn(compare(y, x)) for all x and y. (This implies that compare(x, y) must throw an exception if and only if compare(y, x) throws an exception.)

The implementor must also ensure that the relation is transitive: ((compare(x, y)>0) && (compare(y, z)>0)) implies compare(x, z)>0.

Finally, the implementer must ensure that compare(x, y)==0 implies that sgn(compare(x, z))==sgn(compare(y, z)) for all z.

It is generally the case, but not strictly required that (compare(x, y)==0) == (x.equals(y)). Generally speaking, any comparator that violates this condition should clearly indicate this fact. The recommended language is "Note: this comparator imposes orderings that are inconsistent with equals."

Specified by:

compare in interface Comparator

Parameters:

o1 - the first object to be compared.

o2 - the second object to be compared.

Returns:

a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second.