org.springframework.aop.target
Class AbstractPoolingTargetSource

java.lang.Object
  org.springframework.aop.target.AbstractBeanFactoryBasedTargetSource
      org.springframework.aop.target.AbstractPrototypeBasedTargetSource
          org.springframework.aop.target.AbstractPoolingTargetSource

All Implemented Interfaces:

Serializable, PoolingConfig, TargetSource, BeanFactoryAware, DisposableBean

Direct Known Subclasses:

CommonsPoolTargetSource

public abstract class AbstractPoolingTargetSource
extends AbstractPrototypeBasedTargetSource
implements PoolingConfig, DisposableBean

Abstract superclass for pooling TargetSources that maintains a pool of target instances, acquiring and releasing a target object from the pool for each method invocation. This class is independent of pooling technology.

Subclasses must implement the getTarget() and releaseTarget() methods to work with their chosen pool. The newPrototypeInstance() method inherited from AbstractPrototypeBasedTargetSource can be used to create objects to put in the pool.

Subclasses must also implement some of the monitoring methods from the PoolingConfig interface.

This class provides the getPoolingConfigMixin() method to return an IntroductionAdvisor making these stats available on proxied objects.

This class implements DisposableBean to force subclasses to implement a destroy() method to close down their pool.

Author:

Rod Johnson

See Also:

getTarget(), releaseTarget(java.lang.Object), DisposableBean.destroy(), Serialized Form

Field Summary

Fields inherited from class org.springframework.aop.target.AbstractBeanFactoryBasedTargetSource

logger

Constructor Summary

AbstractPoolingTargetSource()

Method Summary

protected abstract void	createPool() Create the pool.
int	getMaxSize() Return the maximum size of the pool.
DefaultIntroductionAdvisor	getPoolingConfigMixin() Return an IntroductionAdvisor that providing a mixin exposing statistics about the pool maintained by this object.
abstract Object	getTarget() Acquire an object from the pool.
abstract void	releaseTarget(Object target) Return the given object to the pool.
void	setBeanFactory(BeanFactory beanFactory) Set the owning BeanFactory.
void	setMaxSize(int maxSize) Set the maximum size of the pool.

Methods inherited from class org.springframework.aop.target.AbstractPrototypeBasedTargetSource

newPrototypeInstance

Methods inherited from class org.springframework.aop.target.AbstractBeanFactoryBasedTargetSource

copyFrom, getBeanFactory, getTargetBeanName, getTargetClass, isStatic, setTargetBeanName, setTargetClass, writeReplace

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.springframework.aop.target.PoolingConfig

getActiveCount, getIdleCount

Methods inherited from interface org.springframework.beans.factory.DisposableBean

destroy

Constructor Detail

AbstractPoolingTargetSource

public AbstractPoolingTargetSource()

Method Detail

setMaxSize

public void setMaxSize(int maxSize)

Set the maximum size of the pool. Default is -1, indicating no size limit.

getMaxSize

public int getMaxSize()

Return the maximum size of the pool.

Specified by:

getMaxSize in interface PoolingConfig

setBeanFactory

public final void setBeanFactory(BeanFactory beanFactory)
                          throws BeansException

Description copied from class: AbstractBeanFactoryBasedTargetSource

Set the owning BeanFactory. We need to save a reference so that we can use the getBean method on every invocation.

Specified by:

setBeanFactory in interface BeanFactoryAware

Overrides:

setBeanFactory in class AbstractPrototypeBasedTargetSource

Parameters:

beanFactory - owning BeanFactory (may not be null). The bean can immediately call methods on the factory.

Throws:

BeansException - in case of initialization errors

See Also:

BeanInitializationException

createPool

protected abstract void createPool()
                            throws Exception

Create the pool.

Throws:

Exception - to avoid placing constraints on pooling APIs

getTarget

public abstract Object getTarget()
                          throws Exception

Acquire an object from the pool.

Specified by:

getTarget in interface TargetSource

Returns:

an object from the pool

Throws:

Exception - we may need to deal with checked exceptions from pool APIs, so we're forgiving with our exception signature

releaseTarget

public abstract void releaseTarget(Object target)
                            throws Exception

Return the given object to the pool.

Specified by:

releaseTarget in interface TargetSource

Overrides:

releaseTarget in class AbstractBeanFactoryBasedTargetSource

Parameters:

target - object that must have been acquired from the pool via a call to getTarget()

Throws:

Exception - to allow pooling APIs to throw exception

See Also:

getTarget()

getPoolingConfigMixin

public DefaultIntroductionAdvisor getPoolingConfigMixin()

Return an IntroductionAdvisor that providing a mixin exposing statistics about the pool maintained by this object.