org.apache.commons.collections.functors
Class NullPredicate<T>

java.lang.Object
  org.apache.commons.collections.functors.NullPredicate<T>

All Implemented Interfaces:

Serializable, Predicate<T>

public final class NullPredicate<T>
extends Object
implements Predicate<T>, Serializable

Predicate implementation that returns true if the input is null.

Since:

Commons Collections 3.0

Version:

$Revision: 1.1.1.1 $ $Date: 2005/05/23 04:34:32 $

Author:

Matt Hall, John Watkinson, Stephen Colebourne

See Also:

Serialized Form

Field Summary

static Predicate

INSTANCE Singleton predicate instance

Method Summary

boolean	evaluate(T object) Evaluates the predicate returning true if the input is null.
static Predicate	getInstance() Factory returning the singleton instance.

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE

public static final Predicate INSTANCE

Singleton predicate instance

Method Detail

getInstance

public static Predicate getInstance()

Factory returning the singleton instance.

Returns:

the singleton instance

Since:

Commons Collections 3.1

evaluate

public boolean evaluate(T object)

Evaluates the predicate returning true if the input is null.

Specified by:

evaluate in interface Predicate<T>

Parameters:

object - the input object

Returns:

true if input is null