| /* |
| * 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. |
| * |
| * <p>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<K, V> { |
| |
| /** |
| * 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<K> 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<V> values(); |
| } |