/*
* Copyright 2002-2007 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.aop.target;
import org.apache.commons.pool.ObjectPool;
import org.apache.commons.pool.PoolableObjectFactory;
import org.apache.commons.pool.impl.GenericObjectPool;
import org.springframework.beans.BeansException;
import org.springframework.core.Constants;
/**
* TargetSource implementation that holds objects in a configurable
* Jakarta Commons Pool.
*
* <p>By default, an instance of <code>GenericObjectPool</code> is created.
* Subclasses may change the type of <code>ObjectPool</code> used by
* overriding the <code>createObjectPool()</code> method.
*
* <p>Provides many configuration properties mirroring those of the Commons Pool
* <code>GenericObjectPool</code> class; these properties are passed to the
* <code>GenericObjectPool</code> during construction. If creating a subclass of this
* class to change the <code>ObjectPool</code> implementation type, pass in the values
* of configuration properties that are relevant to your chosen implementation.
*
* <p>The <code>testOnBorrow</code>, <code>testOnReturn</code> and <code>testWhileIdle</code>
* properties are explictly not mirrored because the implementation of
* <code>PoolableObjectFactory</code> used by this class does not implement
* meaningful validation. All exposed Commons Pool properties use the corresponding
* Commons Pool defaults: for example,
*
* @author Rod Johnson
* @author Rob Harrop
* @author Juergen Hoeller
* @see GenericObjectPool
* @see #createObjectPool()
* @see #setMaxSize
* @see #setMaxIdle
* @see #setMinIdle
* @see #setMaxWait
* @see #setTimeBetweenEvictionRunsMillis
* @see #setMinEvictableIdleTimeMillis
*/
public class CommonsPoolTargetSource extends AbstractPoolingTargetSource
implements PoolableObjectFactory {
private static final Constants constants = new Constants(GenericObjectPool.class);
private int maxIdle = GenericObjectPool.DEFAULT_MAX_IDLE;
private int minIdle = GenericObjectPool.DEFAULT_MIN_IDLE;
private long maxWait = GenericObjectPool.DEFAULT_MAX_WAIT;
private long timeBetweenEvictionRunsMillis = GenericObjectPool.DEFAULT_TIME_BETWEEN_EVICTION_RUNS_MILLIS;
private long minEvictableIdleTimeMillis = GenericObjectPool.DEFAULT_MIN_EVICTABLE_IDLE_TIME_MILLIS;
private byte whenExhaustedAction = GenericObjectPool.DEFAULT_WHEN_EXHAUSTED_ACTION;
/**
* The Jakarta Commons <code>ObjectPool</code> used to pool target objects
*/
private ObjectPool pool;
/**
* Create a CommonsPoolTargetSource with default settings.
* Default maximum size of the pool is 8.
* @see #setMaxSize
* @see GenericObjectPool#setMaxActive
*/
public CommonsPoolTargetSource() {
setMaxSize(GenericObjectPool.DEFAULT_MAX_ACTIVE);
}
/**
* Set the maximum number of idle objects in the pool.
* Default is 8.
* @see GenericObjectPool#setMaxIdle
*/
public void setMaxIdle(int maxIdle) {
this.maxIdle = maxIdle;
}
/**
* Return the maximum number of idle objects in the pool.
*/
public int getMaxIdle() {
return this.maxIdle;
}
/**
* Set the minimum number of idle objects in the pool.
* Default is 0.
* @see GenericObjectPool#setMinIdle
*/
public void setMinIdle(int minIdle) {
this.minIdle = minIdle;
}
/**
* Return the minimum number of idle objects in the pool.
*/
public int getMinIdle() {
return this.minIdle;
}
/**
* Set the maximum waiting time for fetching an object from the pool.
* Default is -1, waiting forever.
* @see GenericObjectPool#setMaxWait
*/
public void setMaxWait(long maxWait) {
this.maxWait = maxWait;
}
/**
* Return the maximum waiting time for fetching an object from the pool.
*/
public long getMaxWait() {
return this.maxWait;
}
/**
* Set the time between eviction runs that check idle objects whether
* they have been idle for too long or have become invalid.
* Default is -1, not performing any eviction.
* @see GenericObjectPool#setTimeBetweenEvictionRunsMillis
*/
public void setTimeBetweenEvictionRunsMillis(long timeBetweenEvictionRunsMillis) {
this.timeBetweenEvictionRunsMillis = timeBetweenEvictionRunsMillis;
}
/**
* Return the time between eviction runs that check idle objects.
*/
public long getTimeBetweenEvictionRunsMillis() {
return this.timeBetweenEvictionRunsMillis;
}
/**
* Set the minimum time that an idle object can sit in the pool before
* it becomes subject to eviction. Default is 1800000 (30 minutes).
* <p>Note that eviction runs need to be performed to take this
* setting into effect.
* @see #setTimeBetweenEvictionRunsMillis
* @see GenericObjectPool#setMinEvictableIdleTimeMillis
*/
public void setMinEvictableIdleTimeMillis(long minEvictableIdleTimeMillis) {
this.minEvictableIdleTimeMillis = minEvictableIdleTimeMillis;
}
/**
* Return the minimum time that an idle object can sit in the pool.
*/
public long getMinEvictableIdleTimeMillis() {
return this.minEvictableIdleTimeMillis;
}
/**
* Set the action to take when the pool is exhausted. Uses the
* constant names defined in Commons Pool's GenericObjectPool class:
* "WHEN_EXHAUSTED_BLOCK", "WHEN_EXHAUSTED_FAIL", "WHEN_EXHAUSTED_GROW".
* @see #setWhenExhaustedAction(byte)
*/
public void setWhenExhaustedActionName(String whenExhaustedActionName) {
setWhenExhaustedAction(constants.asNumber(whenExhaustedActionName).byteValue());
}
/**
* Set the action to take when the pool is exhausted. Uses the
* constant values defined in Commons Pool's GenericObjectPool class.
* @see GenericObjectPool#setWhenExhaustedAction(byte)
* @see GenericObjectPool#WHEN_EXHAUSTED_BLOCK
* @see GenericObjectPool#WHEN_EXHAUSTED_FAIL
* @see GenericObjectPool#WHEN_EXHAUSTED_GROW
*/
public void setWhenExhaustedAction(byte whenExhaustedAction) {
this.whenExhaustedAction = whenExhaustedAction;
}
/**
* Return the action to take when the pool is exhausted.
*/
public byte getWhenExhaustedAction() {
return whenExhaustedAction;
}
/**
* Creates and holds an ObjectPool instance.
* @see #createObjectPool()
*/
@Override
protected final void createPool() {
logger.debug("Creating Commons object pool");
this.pool = createObjectPool();
}
/**
* Subclasses can override this if they want to return a specific Commons pool.
* They should apply any configuration properties to the pool here.
* <p>Default is a GenericObjectPool instance with the given pool size.
* @return an empty Commons <code>ObjectPool</code>.
* @see org.apache.commons.pool.impl.GenericObjectPool
* @see #setMaxSize
*/
protected ObjectPool createObjectPool() {
GenericObjectPool gop = new GenericObjectPool(this);
gop.setMaxActive(getMaxSize());
gop.setMaxIdle(getMaxIdle());
gop.setMinIdle(getMinIdle());
gop.setMaxWait(getMaxWait());
gop.setTimeBetweenEvictionRunsMillis(getTimeBetweenEvictionRunsMillis());
gop.setMinEvictableIdleTimeMillis(getMinEvictableIdleTimeMillis());
gop.setWhenExhaustedAction(getWhenExhaustedAction());
return gop;
}
/**
* Borrow an object from the <code>ObjectPool</code>.
*/
@Override
public Object getTarget() throws Exception {
return this.pool.borrowObject();
}
/**
* Returns the specified object to the underlying <code>ObjectPool</code>.
*/
@Override
public void releaseTarget(Object target) throws Exception {
this.pool.returnObject(target);
}
public int getActiveCount() throws UnsupportedOperationException {
return this.pool.getNumActive();
}
public int getIdleCount() throws UnsupportedOperationException {
return this.pool.getNumIdle();
}
/**
* Closes the underlying <code>ObjectPool</code> when destroying this object.
*/
public void destroy() throws Exception {
logger.debug("Closing Commons ObjectPool");
this.pool.close();
}
//----------------------------------------------------------------------------
// Implementation of org.apache.commons.pool.PoolableObjectFactory interface
//----------------------------------------------------------------------------
public Object makeObject() throws BeansException {
return newPrototypeInstance();
}
public void destroyObject(Object obj) throws Exception {
destroyPrototypeInstance(obj);
}
public boolean validateObject(Object obj) {
return true;
}
public void activateObject(Object obj) {
}
public void passivateObject(Object obj) {
}
}
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