org.apache.commons.collections.comparators
public class ComparableComparator extends Object implements Comparator, Serializable
null
, not {@link Comparable Comparable},
or for which {@link Comparable#compareTo(Object) compareTo} gave
inconsistent results. This is no longer the case. See
{@link #compare(Object, Object) compare} for details.
Since: Commons Collections 2.0
Version: $Revision: 1.15 $ $Date: 2004/05/15 13:24:11 $
See Also: java.util.Collections#reverseOrder()
Constructor Summary | |
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ComparableComparator()
Constructor whose use should be avoided.
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Method Summary | |
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int | compare(Object obj1, Object obj2)
Compare the two {@link Comparable Comparable} arguments.
|
boolean | equals(Object object)
Returns true iff that Object is
is a {@link Comparator Comparator} whose ordering is
known to be equivalent to mine.
|
static ComparableComparator | getInstance()
Gets the singleton instance of a ComparableComparator.
|
int | hashCode()
Implement a hash code for this comparator that is consistent with
{@link #equals(Object) equals}.
|
Please use the {@link #getInstance()} method whenever possible.
((Comparable)obj1).compareTo(obj2)
Parameters: obj1 the first object to compare obj2 the second object to compare
Returns: negative if obj1 is less, positive if greater, zero if equal
Throws: NullPointerException when obj1 is null
,
or when ((Comparable)obj1).compareTo(obj2)
does ClassCastException when obj1 is not a Comparable
,
or when ((Comparable)obj1).compareTo(obj2)
does
true
iff that Object is
is a {@link Comparator Comparator} whose ordering is
known to be equivalent to mine.
This implementation returns true
iff object.{@link Object#getClass() getClass()}
equals this.getClass()
.
Subclasses may want to override this behavior to remain consistent
with the {@link Comparator#equals(Object)} contract.
Parameters: object the object to compare with
Returns: true if equal
Since: Commons Collections 3.0
Developers are encouraged to use the comparator returned from this method instead of constructing a new instance to reduce allocation and GC overhead when multiple comparable comparators may be used in the same VM.
Returns: the singleton ComparableComparator
Returns: a hash code for this comparator.
Since: Commons Collections 3.0