org.apache.shiro.cache.Cache Maven / Gradle / Ivy
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* 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.shiro.cache;
import java.util.Collection;
import java.util.Set;
/**
* A Cache efficiently stores temporary objects primarily to improve an application's performance.
*
* Shiro doesn't implement a full Cache mechanism itself, since that is outside the core competency of a
* Security framework. Instead, this interface provides an abstraction (wrapper) API on top of an underlying
* cache framework's cache instance (e.g. JCache, Ehcache, JCS, OSCache, JBossCache, TerraCotta, Coherence,
* GigaSpaces, etc, etc), allowing a Shiro user to configure any cache mechanism they choose.
*
* @since 0.2
*/
public interface Cache {
/**
* Returns the Cached value stored under the specified {@code key} or
* {@code null} if there is no Cache entry for that {@code key}.
*
* @param key the key that the value was previous added with
* @return the cached object or {@code null} if there is no entry for the specified {@code key}
* @throws CacheException if there is a problem accessing the underlying cache system
*/
public V get(K key) throws CacheException;
/**
* Adds a Cache entry.
*
* @param key the key used to identify the object being stored.
* @param value the value to be stored in the cache.
* @return the previous value associated with the given {@code key} or {@code null} if there was previous value
* @throws CacheException if there is a problem accessing the underlying cache system
*/
public V put(K key, V value) throws CacheException;
/**
* Remove the cache entry corresponding to the specified key.
*
* @param key the key of the entry to be removed.
* @return the previous value associated with the given {@code key} or {@code null} if there was previous value
* @throws CacheException if there is a problem accessing the underlying cache system
*/
public V remove(K key) throws CacheException;
/**
* Clear all entries from the cache.
*
* @throws CacheException if there is a problem accessing the underlying cache system
*/
public void clear() throws CacheException;
/**
* Returns the number of entries in the cache.
*
* @return the number of entries in the cache.
*/
public int size();
/**
* Returns a view of all the keys for entries contained in this cache.
*
* @return a view of all the keys for entries contained in this cache.
*/
public Set keys();
/**
* Returns a view of all of the values contained in this cache.
*
* @return a view of all of the values contained in this cache.
*/
public Collection values();
}