/*
* Copyright (c) 2009, 2010, 2011, 2012, B3log Team
*
* 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 org.b3log.latke.cache;
import java.io.Serializable;
import java.lang.reflect.Constructor;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.b3log.latke.Latkes;
import org.b3log.latke.RuntimeEnv;
/**
* Cache factory.
*
* @author <a href="mailto:DL88250@gmail.com">Liang Ding</a>
* @version 1.0.0.8, May 3, 2012
*/
public final class CacheFactory {
/**
* Logger.
*/
private static final Logger LOGGER = Logger.getLogger(CacheFactory.class.getName());
/**
* Caches.
*/
private static final Map<String, Cache<String, ?>> CACHES = Collections.synchronizedMap(new HashMap<String, Cache<String, ?>>());
/**
* Removes all caches.
*/
public static synchronized void removeAll() {
RuntimeEnv runtime = Latkes.getRuntime("cache");
if (RuntimeEnv.LOCAL == Latkes.getRuntimeEnv()) { // Always LOCAL cache if runs on a standard servlet container
runtime = RuntimeEnv.LOCAL;
}
switch (runtime) {
case GAE:
final Iterator<Cache<String, ?>> iterator = CACHES.values().iterator();
if (iterator.hasNext()) {
iterator.next().removeAll();
// Clears one will clears all on GAE
break;
}
break;
case LOCAL:
// Clears cache one by one
for (final Map.Entry<String, Cache<String, ?>> entry : CACHES.entrySet()) {
final Cache<String, ?> cache = entry.getValue();
cache.removeAll();
LOGGER.log(Level.FINEST, "Clears cache[name={0}]", entry.getKey());
}
break;
default:
throw new RuntimeException("Latke runs in the hell.... Please set the enviornment correctly");
}
}
/**
* Gets a cache specified by the given cache name.
*
* @param cacheName the given cache name
* @return a cache specified by the given cache name
*/
@SuppressWarnings("unchecked")
public static synchronized Cache<String, ? extends Serializable> getCache(final String cacheName) {
LOGGER.log(Level.INFO, "Constructing Cache[name={0}]....", cacheName);
Cache<String, ?> ret = CACHES.get(cacheName);
try {
if (null == ret) {
switch (Latkes.getRuntime("cache")) {
case LOCAL:
final Class<Cache<String, ?>> localLruCache = (Class<Cache<String, ?>>) Class.forName(
"org.b3log.latke.cache.local.memory.LruMemoryCache");
ret = localLruCache.newInstance();
break;
case GAE:
final Class<Cache<String, ?>> gaeMemcache = (Class<Cache<String, ?>>) Class.forName(
"org.b3log.latke.cache.gae.Memcache");
final Constructor<Cache<String, ?>> constructor = gaeMemcache.getConstructor(String.class);
ret = constructor.newInstance(cacheName);
break;
default:
throw new RuntimeException("Latke runs in the hell.... Please set the enviornment correctly");
}
CACHES.put(cacheName, ret);
}
} catch (final Exception e) {
throw new RuntimeException("Can not get cache: " + e.getMessage(), e);
}
LOGGER.log(Level.INFO, "Constructed Cache[name={0}]", cacheName);
return (Cache<String, Serializable>) ret;
}
/**
* Private default constructor.
*/
private CacheFactory() {
}
}