/*
 * Copyright (C) 2009 eXo Platform SAS.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.exoplatform.services.cache;

import java.io.Serializable;

/**
 * The cache listener allows to be aware of various events that occurs for a cache. For performance reason
 * a listener must perform short time lived operations or should consider to perform jobs asynchronously.
 *
 * Created by The eXo Platform SAS Author : Tuan Nguyen
 * tuan08@users.sourceforge.net Sep 19, 2005
 */
public interface CacheListener<K extends Serializable, V>
{

   /**
    * An entry is expired from the cache.
    *
    * @param context the listener context
    * @param key the entry key
    * @param obj the entry value
    * @throws Exception any exception
    */
   public void onExpire(CacheListenerContext context, K key, V obj) throws Exception;

   /**
    * An entry is removed from the cache.
    *
    * @param context the listener context
    * @param key the entry key
    * @param obj the entry value
    * @throws Exception any exception
    */
   public void onRemove(CacheListenerContext context, K key, V obj) throws Exception;

   /**
    * An entry is inserted in the cache.
    *
    * @param context the listener context
    * @param key the entry key
    * @param obj the entry value
    * @throws Exception any exception
    */
   public void onPut(CacheListenerContext context, K key, V obj) throws Exception;

   /**
    * An entry is retrieved from the cache.
    *
    * @param context the listener context
    * @param key the entry key
    * @param obj the entry value
    * @throws Exception any exception
    */
   public void onGet(CacheListenerContext context, K key, V obj) throws Exception;

   /**
    * The cache is globally cleared.
    *
    * @param context the listener context
    * @throws Exception any exception
    */
   public void onClearCache(CacheListenerContext context) throws Exception;
}
