org.apache.commons.collections

Class FactoryUtils

public class FactoryUtils extends Object

FactoryUtils provides reference implementations and utilities for the Factory functor interface. The supplied factories are: All the supplied factories are Serializable.

Since: Commons Collections 3.0

Version: $Revision: 155406 $ $Date: 2005-02-26 12:55:26 +0000 (Sat, 26 Feb 2005) $

Author: Stephen Colebourne

Constructor Summary
FactoryUtils()
This class is not normally instantiated.
Method Summary
static FactoryconstantFactory(Object constantToReturn)
Creates a Factory that will return the same object each time the factory is used.
static FactoryexceptionFactory()
Gets a Factory that always throws an exception.
static FactoryinstantiateFactory(Class classToInstantiate)
Creates a Factory that can create objects of a specific type using a no-args constructor.
static FactoryinstantiateFactory(Class classToInstantiate, Class[] paramTypes, Object[] args)
Creates a Factory that can create objects of a specific type using the arguments specified to this method.
static FactorynullFactory()
Gets a Factory that will return null each time the factory is used.
static FactoryprototypeFactory(Object prototype)
Creates a Factory that will return a clone of the same prototype object each time the factory is used.

Constructor Detail

FactoryUtils

public FactoryUtils()
This class is not normally instantiated.

Method Detail

constantFactory

public static Factory constantFactory(Object constantToReturn)
Creates a Factory that will return the same object each time the factory is used. 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.

Parameters: constantToReturn the constant object to return each time in the factory

Returns: the constant factory.

See Also:

exceptionFactory

public static Factory exceptionFactory()
Gets a Factory that always throws an exception. This could be useful during testing as a placeholder.

Returns: the factory

See Also:

instantiateFactory

public static Factory instantiateFactory(Class classToInstantiate)
Creates a Factory that can create objects of a specific type using a no-args constructor.

Parameters: classToInstantiate the Class to instantiate each time in the factory

Returns: the reflection factory

Throws: IllegalArgumentException if the classToInstantiate is null

See Also:

instantiateFactory

public static Factory instantiateFactory(Class classToInstantiate, Class[] paramTypes, Object[] args)
Creates a Factory that can create objects of a specific type using the arguments specified to this method.

Parameters: classToInstantiate the Class to instantiate each time in the factory paramTypes parameter types for the constructor, can be null args the arguments to pass to the constructor, can be null

Returns: the reflection factory

Throws: IllegalArgumentException if the classToInstantiate is null IllegalArgumentException if the paramTypes and args don't match IllegalArgumentException if the constructor doesn't exist

See Also:

nullFactory

public static Factory nullFactory()
Gets a Factory that will return null each time the factory is used. This could be useful during testing as a placeholder.

Returns: the factory

See Also:

prototypeFactory

public static Factory prototypeFactory(Object prototype)
Creates a Factory that will return a clone of the same prototype object each time the factory is used. The prototype will be cloned using one of these techniques (in order):
Copyright © 2001-2008 Apache Software Foundation. All Rights Reserved.