org.apache.commons.pool.impl

Class SoftReferenceObjectPool

java.lang.Object

org.apache.commons.pool.BaseObjectPool

org.apache.commons.pool.impl.SoftReferenceObjectPool

All Implemented Interfaces:

ObjectPool

public class SoftReferenceObjectPool
extends BaseObjectPool
implements ObjectPool

A SoftReference based ObjectPool.

Version:

$Revision: 383290 $ $Date: 2006-03-05 02:00:15 -0500 (Sun, 05 Mar 2006) $

Author:

Rodney Waldhoff

Constructor Summary

Constructors

Constructor and Description
SoftReferenceObjectPool()
SoftReferenceObjectPool(PoolableObjectFactory factory)
SoftReferenceObjectPool(PoolableObjectFactory factory, int initSize)

Method Summary

Methods

Modifier and Type	Method and Description
void	addObject() Create an object, and place it into the pool.
java.lang.Object	borrowObject() Obtain an instance from my pool.
void	clear() Not supported in this base implementation.
void	close() Close this pool, and free any resources associated with it.
int	getNumActive() Not supported in this base implementation.
int	getNumIdle() Returns an approximation not less than the of the number of idle instances in the pool.
void	invalidateObject(java.lang.Object obj) Invalidates an object from the pool By contract, obj MUST have been obtained using borrowObject or a related method as defined in an implementation or sub-interface.
void	returnObject(java.lang.Object obj) Return an instance to my pool.
void	setFactory(PoolableObjectFactory factory) Not supported in this base implementation.

Methods inherited from class java.lang.Object

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

Constructor Detail

SoftReferenceObjectPool

public SoftReferenceObjectPool()

SoftReferenceObjectPool

public SoftReferenceObjectPool(PoolableObjectFactory factory)

SoftReferenceObjectPool

public SoftReferenceObjectPool(PoolableObjectFactory factory,
                       int initSize)
                        throws java.lang.Exception

Throws:

java.lang.Exception

Method Detail

addObject

public void addObject()
               throws java.lang.Exception

Create an object, and place it into the pool. addObject() is useful for "pre-loading" a pool with idle objects.

Specified by:

addObject in interface ObjectPool

Overrides:

addObject in class BaseObjectPool

Throws:

java.lang.Exception

borrowObject

public java.lang.Object borrowObject()
                              throws java.lang.Exception

Description copied from interface: ObjectPool

Obtain an instance from my pool. By contract, clients MUST return the borrowed instance using returnObject or a related method as defined in an implementation or sub-interface.

The behaviour of this method when the pool has been exhausted is not specified (although it may be specified by implementations).

Specified by:

borrowObject in interface ObjectPool

Specified by:

borrowObject in class BaseObjectPool

Returns:

an instance from my pool.

Throws:

java.lang.Exception

clear

public void clear()

Description copied from class: BaseObjectPool

Not supported in this base implementation.

Specified by:

clear in interface ObjectPool

Overrides:

clear in class BaseObjectPool

close

public void close()
           throws java.lang.Exception

Description copied from interface: ObjectPool

Close this pool, and free any resources associated with it.

Specified by:

close in interface ObjectPool

Overrides:

close in class BaseObjectPool

Throws:

java.lang.Exception

getNumActive

public int getNumActive()

Description copied from class: BaseObjectPool

Not supported in this base implementation.

Specified by:

getNumActive in interface ObjectPool

Overrides:

getNumActive in class BaseObjectPool

Returns:

the number of instances currently borrowed in my pool

getNumIdle

public int getNumIdle()

Returns an approximation not less than the of the number of idle instances in the pool.

Specified by:

getNumIdle in interface ObjectPool

Overrides:

getNumIdle in class BaseObjectPool

Returns:

the number of instances currently idle in my pool

invalidateObject

public void invalidateObject(java.lang.Object obj)
                      throws java.lang.Exception

Description copied from interface: ObjectPool

Invalidates an object from the pool By contract, obj MUST have been obtained using borrowObject or a related method as defined in an implementation or sub-interface.

This method should be used when an object that has been borrowed is determined (due to an exception or other problem) to be invalid. If the connection should be validated before or after borrowing, then the PoolableObjectFactory.validateObject(java.lang.Object) method should be used instead.

Specified by:

invalidateObject in interface ObjectPool

Specified by:

invalidateObject in class BaseObjectPool

Parameters:

obj - a borrowed instance to be returned.

Throws:

java.lang.Exception

returnObject

public void returnObject(java.lang.Object obj)
                  throws java.lang.Exception

Description copied from interface: ObjectPool

Return an instance to my pool. By contract, obj MUST have been obtained using borrowObject or a related method as defined in an implementation or sub-interface.

Specified by:

returnObject in interface ObjectPool

Specified by:

returnObject in class BaseObjectPool

Parameters:

obj - a borrowed instance to be returned.

Throws:

java.lang.Exception

setFactory

public void setFactory(PoolableObjectFactory factory)
                throws java.lang.IllegalStateException

Description copied from class: BaseObjectPool

Not supported in this base implementation.

Specified by:

setFactory in interface ObjectPool

Overrides:

setFactory in class BaseObjectPool

Parameters:

factory - the PoolableObjectFactory I use to create new instances.

Throws:

java.lang.IllegalStateException - when the factory cannot be set at this time