gate.util.spring
Class DuplicateResourceFactoryBean

java.lang.Object
  gate.util.spring.GateAwareObject
      gate.util.spring.DuplicateResourceFactoryBean

All Implemented Interfaces:

org.springframework.beans.factory.BeanFactoryAware, org.springframework.beans.factory.DisposableBean, org.springframework.beans.factory.FactoryBean

public class DuplicateResourceFactoryBean
extends GateAwareObject
implements org.springframework.beans.factory.FactoryBean, org.springframework.beans.factory.DisposableBean

Spring factory bean to create duplicate copies of a GATE resource. This bean would typically be declared with singleton scope, but the factory produces a new duplicate of its template resource each time getBean is called (or each time it is injected as a dependency).

Field Summary

private List<ResourceCustomiser>	customisers Customisers that are applied to the duplicated resource before it is returned.
private List<WeakReference<Resource>>	resourcesReturned A list of weak references to the duplicates that have been returned, so they can be freed when this factory bean is disposed.
private boolean	returnTemplate Should we return the template itself the first time getObject() is called, or should we keep it for use only as a template and just return duplicates?
private Resource	templateResource The template resource which we will duplicate.
private Class<?>	typeClass

Constructor Summary

DuplicateResourceFactoryBean()

Method Summary

void	destroy() Delete the duplicates we have returned, unless they have already been freed.
Object	getObject()
Class<?>	getObjectType() Returns a proxy class that implements the same set of GATE interfaces as the template resource.
boolean	isSingleton() This factory is not a singleton - it produces a new object each time getObject() is called.
void	setCustomisers(List<ResourceCustomiser> customisers) Optional customisers that will be applied to the duplicate resource before it is returned.
void	setReturnTemplate(boolean returnTemplate) Should this factory bean return the template resource itself the first time getObject() is called, or should it always return a duplicate, keeping the template in pristine condition.
void	setTemplate(Resource template) Set the template resource that this factory bean will duplicate.

Methods inherited from class gate.util.spring.GateAwareObject

ensureGateInit, setBeanFactory

Methods inherited from class java.lang.Object

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

Field Detail

templateResource

private Resource templateResource

The template resource which we will duplicate.

returnTemplate

private boolean returnTemplate

Should we return the template itself the first time getObject() is called, or should we keep it for use only as a template and just return duplicates?

customisers

private List<ResourceCustomiser> customisers

Customisers that are applied to the duplicated resource before it is returned.

resourcesReturned

private List<WeakReference<Resource>> resourcesReturned

A list of weak references to the duplicates that have been returned, so they can be freed when this factory bean is disposed.

typeClass

private Class<?> typeClass

Constructor Detail

DuplicateResourceFactoryBean

public DuplicateResourceFactoryBean()

Method Detail

setTemplate

public void setTemplate(Resource template)

Set the template resource that this factory bean will duplicate.

setReturnTemplate

public void setReturnTemplate(boolean returnTemplate)

Should this factory bean return the template resource itself the first time getObject() is called, or should it always return a duplicate, keeping the template in pristine condition. Generally, if the duplicates will all be created up-front, and there are no configured customisers, then it is safe to set this option to true. In cases where the duplicates may be created asynchronously (possibly creating one duplicate while another one is in use in a different thread) or may be customised after creation it is safer to set this option to false (the default) to keep the template pristine and always return duplicates.

setCustomisers

public void setCustomisers(List<ResourceCustomiser> customisers)

Optional customisers that will be applied to the duplicate resource before it is returned. If customisers are specified then it is strongly recommended to leave the returnTemplate option set to false.

getObject

public Object getObject()
                 throws Exception

Specified by:

getObject in interface org.springframework.beans.factory.FactoryBean

Throws:

Exception

getObjectType

public Class<?> getObjectType()

Returns a proxy class that implements the same set of GATE interfaces as the template resource. See Factory.duplicate(Resource) for the list of interfaces that will be considered.

Specified by:

getObjectType in interface org.springframework.beans.factory.FactoryBean

isSingleton

public boolean isSingleton()

This factory is not a singleton - it produces a new object each time getObject() is called.

Specified by:

isSingleton in interface org.springframework.beans.factory.FactoryBean

destroy

public void destroy()

Delete the duplicates we have returned, unless they have already been freed.

Specified by:

destroy in interface org.springframework.beans.factory.DisposableBean