| /* |
| * 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.Collections; |
| import java.util.Map; |
| import java.util.Set; |
| |
| /** |
| * A <code>MapCache</code> is a {@link Cache Cache} implementation that uses a backing {@link Map} instance to store |
| * and retrieve cached data. |
| * |
| * @since 1.0 |
| */ |
| public class MapCache<K, V> implements Cache<K, V> { |
| |
| /** |
| * Backing instance. |
| */ |
| private final Map<K, V> map; |
| |
| /** |
| * The name of this cache. |
| */ |
| private final String name; |
| |
| public MapCache(String name, Map<K, V> backingMap) { |
| if (name == null) { |
| throw new IllegalArgumentException("Cache name cannot be null."); |
| } |
| if (backingMap == null) { |
| throw new IllegalArgumentException("Backing map cannot be null."); |
| } |
| this.name = name; |
| this.map = backingMap; |
| } |
| |
| public V get(K key) throws CacheException { |
| return map.get(key); |
| } |
| |
| public V put(K key, V value) throws CacheException { |
| return map.put(key, value); |
| } |
| |
| public V remove(K key) throws CacheException { |
| return map.remove(key); |
| } |
| |
| public void clear() throws CacheException { |
| map.clear(); |
| } |
| |
| public int size() { |
| return map.size(); |
| } |
| |
| public Set<K> keys() { |
| Set<K> keys = map.keySet(); |
| if (!keys.isEmpty()) { |
| return Collections.unmodifiableSet(keys); |
| } |
| return Collections.emptySet(); |
| } |
| |
| public Collection<V> values() { |
| Collection<V> values = map.values(); |
| if (!values.isEmpty()) { |
| return Collections.unmodifiableCollection(values); |
| } |
| return Collections.emptyList(); |
| } |
| |
| public String toString() { |
| return new StringBuilder("MapCache '") |
| .append(name).append("' (") |
| .append(map.size()) |
| .append(" entries)") |
| .toString(); |
| } |
| } |