NullPredicate

java.lang.Object
- org.apache.commons.collections.functors.NullPredicate

All Implemented Interfaces:

java.io.Serializable, Predicate
```
public final class NullPredicate
extends java.lang.Object
implements Predicate, java.io.Serializable
```
Predicate implementation that returns true if the input is null.

Since:

Commons Collections 3.0

Version:

$Revision: 646777 $ $Date: 2008-04-10 14:33:15 +0200 (Thu, 10 Apr 2008) $

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type Field Description

static Predicate INSTANCE
Singleton predicate instance

private static long serialVersionUID
Serial version UID

Constructor Summary

Constructors
Modifier Constructor Description

private NullPredicate()
Restricted constructor.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`evaluate(java.lang.Object 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
  - serialVersionUID
```
private static final long serialVersionUID
```
    Serial version UID
    
    See Also:
    
    Constant Field Values
  - INSTANCE
```
public static final Predicate INSTANCE
```
    Singleton predicate instance
- Constructor Detail
  - NullPredicate
```
private NullPredicate()
```
    Restricted constructor.
- 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(java.lang.Object object)
```
    Evaluates the predicate returning true if the input is null.
    
    Specified by:
    
    evaluate in interface Predicate
    
    Parameters:
    
    object - the input object
    
    Returns:
    
    true if input is null