/*
* Copyright 2014 Attila Szegedi, Daniel Dekany, Jonathan Revusky
*
* Licensed 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 freemarker.cache;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
/**
* Strong cache storage is a cache storage that simply wraps a {@link Map}. It holds a strong reference to all objects
* it was passed, therefore prevents the cache from being purged during garbage collection. This class is always
* thread-safe since 2.3.24, before that if we are running on Java 5 or later.
*
* @see freemarker.template.Configuration#setCacheStorage(CacheStorage)
*/
public class StrongCacheStorage implements ConcurrentCacheStorage, CacheStorageWithGetSize {
private final Map map = new ConcurrentHashMap();
/**
* Always returns {@code true}.
*/
public boolean isConcurrent() {
return true;
}
public Object get(Object key) {
return map.get(key);
}
public void put(Object key, Object value) {
map.put(key, value);
}
public void remove(Object key) {
map.remove(key);
}
/**
* Returns a close approximation of the number of cache entries.
*
* @since 2.3.21
*/
public int getSize() {
return map.size();
}
public void clear() {
map.clear();
}
}