/*
* Copyright 1999-2004 The Apache Software Foundation.
*
* 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 com.frameworkset.commons.pool;
/**
* An interface defining life-cycle methods for
* instances to be used in an
* {@link ObjectPool ObjectPool}.
* <p>
* By contract, when an {@link ObjectPool ObjectPool}
* delegates to a <tt>PoolableObjectFactory</tt>,
* <ol>
* <li>
* {@link #makeObject makeObject}
* is called whenever a new instance is needed.
* </li>
* <li>
* {@link #activateObject activateObject}
* is invoked on every instance before it is returned from the
* pool.
* </li>
* <li>
* {@link #passivateObject passivateObject}
* is invoked on every instance when it is returned to the
* pool.
* </li>
* <li>
* {@link #destroyObject destroyObject}
* is invoked on every instance when it is being "dropped" from the
* pool (whether due to the response from
* {@link #validateObject validateObject}, or
* for reasons specific to the pool implementation.)
* </li>
* <li>
* {@link #validateObject validateObject}
* is invoked in an implementation-specific fashion to determine if an instance
* is still valid to be returned by the pool.
* It will only be invoked on an {@link #activateObject "activated"}
* instance.
* </li>
* </ol>
*
* @see ObjectPool
*
* @author Rodney Waldhoff
* @version $Revision: 155430 $ $Date: 2005-02-26 08:13:28 -0500 (Sat, 26 Feb 2005) $
*/
public interface PoolableObjectFactory {
/**
* Creates an instance that can be returned by the pool.
* @return an instance that can be returned by the pool.
*/
Object makeObject() throws Exception;
/**
* Destroys an instance no longer needed by the pool.
* @param obj the instance to be destroyed
*/
void destroyObject(Object obj) throws Exception;
/**
* Ensures that the instance is safe to be returned by the pool.
* Returns <tt>false</tt> if this object should be destroyed.
* @param obj the instance to be validated
* @return <tt>false</tt> if this <i>obj</i> is not valid and should
* be dropped from the pool, <tt>true</tt> otherwise.
*/
boolean validateObject(Object obj);
/**
* Reinitialize an instance to be returned by the pool.
* @param obj the instance to be activated
*/
void activateObject(Object obj) throws Exception;
/**
* Uninitialize an instance to be returned to the pool.
* @param obj the instance to be passivated
*/
void passivateObject(Object obj) throws Exception;
}