| /* |
| * 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 org.apache.shiro.util.Destroyable; |
| import org.apache.shiro.util.LifecycleUtils; |
| import org.apache.shiro.util.StringUtils; |
| |
| import java.util.Collection; |
| import java.util.concurrent.ConcurrentHashMap; |
| import java.util.concurrent.ConcurrentMap; |
| |
| /** |
| * Very simple abstract {@code CacheManager} implementation that retains all created {@link Cache Cache} instances in |
| * an in-memory {@link ConcurrentMap ConcurrentMap}. {@code Cache} instance creation is left to subclasses via |
| * the {@link #createCache createCache} method implementation. |
| * |
| * @since 1.0 |
| */ |
| public abstract class AbstractCacheManager implements CacheManager, Destroyable { |
| |
| /** |
| * Retains all Cache objects maintained by this cache manager. |
| */ |
| private final ConcurrentMap<String, Cache> caches; |
| |
| /** |
| * Default no-arg constructor that instantiates an internal name-to-cache {@code ConcurrentMap}. |
| */ |
| public AbstractCacheManager() { |
| this.caches = new ConcurrentHashMap<String, Cache>(); |
| } |
| |
| /** |
| * Returns the cache with the specified {@code name}. If the cache instance does not yet exist, it will be lazily |
| * created, retained for further access, and then returned. |
| * |
| * @param name the name of the cache to acquire. |
| * @return the cache with the specified {@code name}. |
| * @throws IllegalArgumentException if the {@code name} argument is {@code null} or does not contain text. |
| * @throws CacheException if there is a problem lazily creating a {@code Cache} instance. |
| */ |
| public <K, V> Cache<K, V> getCache(String name) throws IllegalArgumentException, CacheException { |
| if (!StringUtils.hasText(name)) { |
| throw new IllegalArgumentException("Cache name cannot be null or empty."); |
| } |
| |
| Cache cache; |
| |
| cache = caches.get(name); |
| if (cache == null) { |
| cache = createCache(name); |
| Cache existing = caches.putIfAbsent(name, cache); |
| if (existing != null) { |
| cache = existing; |
| } |
| } |
| |
| //noinspection unchecked |
| return cache; |
| } |
| |
| /** |
| * Creates a new {@code Cache} instance associated with the specified {@code name}. |
| * |
| * @param name the name of the cache to create |
| * @return a new {@code Cache} instance associated with the specified {@code name}. |
| * @throws CacheException if the {@code Cache} instance cannot be created. |
| */ |
| protected abstract Cache createCache(String name) throws CacheException; |
| |
| /** |
| * Cleanup method that first {@link LifecycleUtils#destroy destroys} all of it's managed caches and then |
| * {@link java.util.Map#clear clears} out the internally referenced cache map. |
| * |
| * @throws Exception if any of the managed caches can't destroy properly. |
| */ |
| public void destroy() throws Exception { |
| while (!caches.isEmpty()) { |
| for (Cache cache : caches.values()) { |
| LifecycleUtils.destroy(cache); |
| } |
| caches.clear(); |
| } |
| } |
| |
| public String toString() { |
| Collection<Cache> values = caches.values(); |
| StringBuilder sb = new StringBuilder(getClass().getSimpleName()) |
| .append(" with ") |
| .append(caches.size()) |
| .append(" cache(s)): ["); |
| int i = 0; |
| for (Cache cache : values) { |
| if (i > 0) { |
| sb.append(", "); |
| } |
| sb.append(cache.toString()); |
| i++; |
| } |
| sb.append("]"); |
| return sb.toString(); |
| } |
| } |