/**
* 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.camel.impl;
import java.util.Map;
import org.apache.camel.CamelContext;
import org.apache.camel.Endpoint;
import org.apache.camel.Exchange;
import org.apache.camel.FailedToCreateConsumerException;
import org.apache.camel.IsSingleton;
import org.apache.camel.PollingConsumer;
import org.apache.camel.util.CamelContextHelper;
import org.apache.camel.util.LRUCache;
import org.apache.camel.util.LRUSoftCache;
import org.apache.camel.util.ServiceHelper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Cache containing created {@link org.apache.camel.Consumer}.
*
* @version
*/
public class ConsumerCache extends ServiceSupport {
private static final transient Logger LOG = LoggerFactory.getLogger(ConsumerCache.class);
private final CamelContext camelContext;
private final Map<String, PollingConsumer> consumers;
private final Object source;
public ConsumerCache(Object source, CamelContext camelContext) {
this(source, camelContext, CamelContextHelper.getMaximumCachePoolSize(camelContext));
}
public ConsumerCache(Object source, CamelContext camelContext, int cacheSize) {
this(source, camelContext, createLRUCache(cacheSize));
}
public ConsumerCache(Object source, CamelContext camelContext, Map<String, PollingConsumer> cache) {
this.camelContext = camelContext;
this.consumers = cache;
this.source = source;
}
/**
* Creates the {@link LRUCache} to be used.
* <p/>
* This implementation returns a {@link org.apache.camel.util.LRUSoftCache} instance.
* @param cacheSize the cache size
* @return the cache
*/
protected static LRUCache<String, PollingConsumer> createLRUCache(int cacheSize) {
// We use a soft reference cache to allow the JVM to re-claim memory if it runs low on memory.
return new LRUSoftCache<String, PollingConsumer>(cacheSize);
}
public synchronized PollingConsumer getConsumer(Endpoint endpoint) {
String key = endpoint.getEndpointUri();
PollingConsumer answer = consumers.get(key);
if (answer == null) {
try {
answer = endpoint.createPollingConsumer();
answer.start();
} catch (Exception e) {
throw new FailedToCreateConsumerException(endpoint, e);
}
boolean singleton = true;
if (answer instanceof IsSingleton) {
singleton = ((IsSingleton) answer).isSingleton();
}
if (singleton) {
LOG.debug("Adding to consumer cache with key: {} for consumer: {}", endpoint, answer);
consumers.put(key, answer);
} else {
LOG.debug("Consumer for endpoint: {} is not singleton and thus not added to consumer cache", key);
}
}
return answer;
}
public Exchange receive(Endpoint endpoint) {
LOG.debug("<<<< {}", endpoint);
PollingConsumer consumer = getConsumer(endpoint);
return consumer.receive();
}
public Exchange receive(Endpoint endpoint, long timeout) {
LOG.debug("<<<< {}", endpoint);
PollingConsumer consumer = getConsumer(endpoint);
return consumer.receive(timeout);
}
public Exchange receiveNoWait(Endpoint endpoint) {
LOG.debug("<<<< {}", endpoint);
PollingConsumer consumer = getConsumer(endpoint);
return consumer.receiveNoWait();
}
public CamelContext getCamelContext() {
return camelContext;
}
/**
* Gets the source which uses this cache
*
* @return the source
*/
public Object getSource() {
return source;
}
/**
* Returns the current size of the cache
*
* @return the current size
*/
public int size() {
int size = consumers.size();
LOG.trace("size = {}", size);
return size;
}
/**
* Gets the maximum cache size (capacity).
* <p/>
* Will return <tt>-1</tt> if it cannot determine this if a custom cache was used.
*
* @return the capacity
*/
public int getCapacity() {
int capacity = -1;
if (consumers instanceof LRUCache) {
LRUCache cache = (LRUCache) consumers;
capacity = cache.getMaxCacheSize();
}
return capacity;
}
/**
* Gets the cache hits statistic
* <p/>
* Will return <tt>-1</tt> if it cannot determine this if a custom cache was used.
*
* @return the hits
*/
public long getHits() {
long hits = -1;
if (consumers instanceof LRUCache) {
LRUCache cache = (LRUCache) consumers;
hits = cache.getHits();
}
return hits;
}
/**
* Gets the cache misses statistic
* <p/>
* Will return <tt>-1</tt> if it cannot determine this if a custom cache was used.
*
* @return the misses
*/
public long getMisses() {
long misses = -1;
if (consumers instanceof LRUCache) {
LRUCache cache = (LRUCache) consumers;
misses = cache.getMisses();
}
return misses;
}
/**
* Resets the cache statistics
*/
public void resetCacheStatistics() {
if (consumers instanceof LRUCache) {
LRUCache cache = (LRUCache) consumers;
cache.resetStatistics();
}
}
/**
* Purges this cache
*/
public synchronized void purge() {
consumers.clear();
}
@Override
public String toString() {
return "ConsumerCache for source: " + source + ", capacity: " + getCapacity();
}
protected void doStart() throws Exception {
ServiceHelper.startServices(consumers);
}
protected void doStop() throws Exception {
ServiceHelper.stopServices(consumers);
consumers.clear();
}
}