/**
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.apache.activemq.memory;
/**
* Defines the interface used to cache messages.
*/
public interface Cache {
/**
* Gets an object that was previously <code>put</code> into this object.
*
* @param key
* @return null if the object was not previously put or if the object has
* expired out of the cache.
*/
Object get(Object key);
/**
* Puts an object into the cache.
*
* @param key
* @param value
*/
Object put(Object key, Object value);
/**
* Removes an object from the cache.
*
* @param key
* @return the object associated with the key if it was still in the cache.
*/
Object remove(Object key);
/**
* Lets a cache know it will not be used any further and that it can release
* acquired resources
*/
void close();
/**
* How big is the cache right now?
*
* @return the size.
*/
int size();
}