/*
* Copyright 2011 - 2012 M3, Inc.
*
* 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 com.m3.methodcache.interceptor;
import com.m3.memcached.facade.Configuration;
import com.m3.memcached.facade.MemcachedClient;
import com.m3.memcached.facade.MemcachedClientPool;
import com.m3.methodcache.annotation.CacheResult;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.annotation.Resource;
/**
* CacheResultInterceptor using Memcached
*/
public class MemcachedCacheResultInterceptor extends AbstractCacheResultInterceptor implements MethodInterceptor {
private Logger log = LoggerFactory.getLogger(MemcachedCacheResultInterceptor.class);
/**
* If necessary, override this to provider {@link Configuration} instance.
*
* @return Configuration
*/
public Configuration getConfiguration() {
return null;
}
/**
* Memcached configuration
*/
@Resource
private Configuration config = getConfiguration();
private MemcachedClientPool pool;
private volatile boolean isPoolInitialized = false;
public void initializePool() throws Exception {
pool = new MemcachedClientPool(config);
isPoolInitialized = true;
}
@Override
public Object invoke(MethodInvocation invocation) throws Throwable {
CacheResult annotation = getCacheResultAnnotation(invocation);
if (annotation != null) {
if (!isPoolInitialized) {
initializePool();
}
MemcachedClient memcached = pool.getClient();
String cacheKey = annotation.cacheKey().equals("") ? getCacheKey(invocation, isUsingRawKey()) : annotation.cacheKey();
Object cachedObject = null;
try {
cachedObject = memcached.get(cacheKey);
} catch (Throwable t) {
if (log.isDebugEnabled()) {
log.debug("Failed to get a value from memcached servers. (" + cacheKey + ")", t);
}
}
if (cachedObject != null) {
return cachedObject;
} else {
Object value = invocation.proceed();
try {
memcached.set(cacheKey, annotation.secondsToExpire(), value);
} catch (Throwable t) {
if (log.isDebugEnabled()) {
log.debug("Failed to set a value to memcached servers. (" + cacheKey + " -> " + value + ")", t);
}
}
return value;
}
}
return invocation.proceed();
}
public void destroy() {
pool.shutdown();
log.info("Destroyed memcached connection pool. (namespace: " + config.getNamespace() + ")");
}
}