/**************************************************************************************
* Copyright (C) 2008 EsperTech, Inc. All rights reserved. *
* http://esper.codehaus.org *
* http://www.espertech.com *
* ---------------------------------------------------------------------------------- *
* The software in this package is published under the terms of the GPL license *
* a copy of which has been included with this distribution in the license.txt file. *
**************************************************************************************/
package com.espertech.esper.client;
/**
* Enum indicating what kind of references are used to store the cache map's keys and values.
*/
public enum ConfigurationCacheReferenceType
{
/**
* Constant indicating that hard references should be used.
* <p>
* Does not allow garbage collection to remove cache entries.
*/
HARD,
/**
* Constant indicating that soft references should be used.
* <p>
* Allows garbage collection to remove cache entries only after all weak references have been collected.
*/
SOFT,
/**
* Constant indicating that weak references should be used.
* <p>
* Allows garbage collection to remove cache entries.
*/
WEAK;
/**
* The default policy is set to WEAK to reduce the chance that out-of-memory errors occur
* as caches fill, and stay backwards compatible with prior Esper releases.
* @return default reference type
*/
public static ConfigurationCacheReferenceType getDefault()
{
return WEAK;
}
}