Package org.apache.commons.collections4.functors

Class ConstantFactory<T>

java.lang.Object

org.apache.commons.collections4.functors.ConstantFactory<T>

All Implemented Interfaces:

java.io.Serializable, Factory<T>

public class ConstantFactory<T>
extends java.lang.Object
implements Factory<T>, java.io.Serializable

Factory implementation that returns the same constant each time.

No check is made that the object is immutable. In general, only immutable objects should use the constant factory. Mutable objects should use the prototype factory.

Since:

3.0

Version:

$Id: ConstantFactory.java 1543950 2013-11-20 21:13:35Z tn $

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field	Description
static Factory	NULL_INSTANCE	Returns null each time

Constructor Summary

Constructors

Constructor	Description
ConstantFactory(T constantToReturn)	Constructor that performs no validation.

Method Summary

Modifier and Type	Method	Description
static <T> Factory<T>	constantFactory(T constantToReturn)	Factory method that performs validation.
T	create()	Always return constant.
T	getConstant()	Gets the constant.

Methods inherited from class java.lang.Object

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

Field Detail

NULL_INSTANCE

public static final Factory NULL_INSTANCE

Returns null each time

Constructor Detail

ConstantFactory

public ConstantFactory(T constantToReturn)

Constructor that performs no validation. Use constantFactory if you want that.

Parameters:

constantToReturn - the constant to return each time

Method Detail

constantFactory

public static <T> Factory<T> constantFactory(T constantToReturn)

Factory method that performs validation.

Type Parameters:

T - the type of the constant

Parameters:

constantToReturn - the constant object to return each time in the factory

Returns:

the constant factory.

create

public T create()

Always return constant.

Specified by:

create in interface Factory<T>

Returns:

the stored constant value

getConstant

public T getConstant()

Gets the constant.

Returns:

the constant

Since:

3.1