org.apache.commons.collections.functors

Class ConstantFactory

Implemented Interfaces:
Factory, Serializable

public class ConstantFactory
extends java.lang.Object
implements Factory, 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.

Version:
$Revision: 1.5 $ $Date: 2004/05/16 11:47:38 $
Author:
Stephen Colebourne
Since:
Commons Collections 3.0

Field Summary

static Factory
NULL_INSTANCE
Returns null each time

Constructor Summary

ConstantFactory(Object constantToReturn)
Constructor that performs no validation.

Method Summary

Object
create()
Always return constant.
Object
getConstant()
Gets the constant.
static Factory
getInstance(Object constantToReturn)
Factory method that performs validation.

Field Details

NULL_INSTANCE

public static final Factory NULL_INSTANCE
Returns null each time

Constructor Details

ConstantFactory

public ConstantFactory(Object constantToReturn)
Constructor that performs no validation. Use getInstance if you want that.
Parameters:
constantToReturn - the constant to return each time

Method Details

create

public Object create()
Always return constant.
Specified by:
create in interface Factory
Returns:
the stored constant value

getConstant

public Object getConstant()
Gets the constant.
Returns:
the constant
Since:
Commons Collections 3.1

getInstance

public static Factory getInstance(Object constantToReturn)
Factory method that performs validation.
Parameters:
constantToReturn - the constant object to return each time in the factory
Returns:
the constant factory.

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