Package org.apache.fulcrum.factory

Interface Factory<T>

public interface Factory<T>

Factory is an interface for object factories. Object factories can be registered with the Factory Service to support customized functionality during instantiation of specific classes that the service itself cannot provide. Examples include instantiation of XML parsers and secure sockets requiring provider specific initializations before instantiation.

Version:

$Id$

Author:

Ilkka Priha, Stephen McConnell

Method Summary

Modifier and Type	Method	Description
T	getInstance()	Gets an instance of a class.
T	getInstance(ClassLoader loader)	Gets an instance of a class using a specified class loader.
T	getInstance(ClassLoader loader, Object[] params, String[] signature)	Gets an instance of a named class using a specified class loader.
T	getInstance(Object[] params, String[] signature)	Gets an instance of a named class.
void	init(String className)	Initializes the factory.
boolean	isLoaderSupported()	Tests if this object factory supports specified class loaders.

Method Detail

init

void init(String className)
   throws FactoryException

Initializes the factory. This method is called by the Factory Service before the factory is used.

Parameters:

className - the name of the production class

Throws:

FactoryException - if initialization fails.

getInstance

T getInstance()
       throws FactoryException

Gets an instance of a class.

Returns:

the instance.

Throws:

FactoryException - if instantiation fails.

getInstance

T getInstance(ClassLoader loader)
       throws FactoryException

Gets an instance of a class using a specified class loader.

Class loaders are supported only if the isLoaderSupported method returns true. Otherwise the loader parameter is ignored.

Parameters:

loader - the class loader.

Returns:

the instance.

Throws:

FactoryException - if instantiation fails.

getInstance

T getInstance(Object[] params,
              String[] signature)
       throws FactoryException

Gets an instance of a named class. Parameters for its constructor are given as an array of objects, primitive types must be wrapped with a corresponding class.

Parameters:

params - an array containing the parameters of the constructor.

signature - an array containing the signature of the constructor.

Returns:

the instance.

Throws:

FactoryException - if instantiation fails.

getInstance

T getInstance(ClassLoader loader,
              Object[] params,
              String[] signature)
       throws FactoryException

Gets an instance of a named class using a specified class loader. Parameters for its constructor are given as an array of objects, primitive types must be wrapped with a corresponding class.

Class loaders are supported only if the isLoaderSupported method returns true. Otherwise the loader parameter is ignored.

Parameters:

loader - the class loader.

params - an array containing the parameters of the constructor.

signature - an array containing the signature of the constructor.

Returns:

the instance.

Throws:

FactoryException - if instantiation fails.

isLoaderSupported

boolean isLoaderSupported()

Tests if this object factory supports specified class loaders.

Returns:

true if class loaders are supported, false otherwise.