/*
* 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.qpid.jms.policy;
import org.apache.qpid.jms.JmsDestination;
import org.apache.qpid.jms.JmsSession;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Defines the prefetch message policies for different types of consumers
*/
public class JmsDefaultPrefetchPolicy implements JmsPrefetchPolicy {
public static final int MAX_PREFETCH_SIZE = Short.MAX_VALUE;
public static final int DEFAULT_QUEUE_PREFETCH = 1000;
public static final int DEFAULT_QUEUE_BROWSER_PREFETCH = DEFAULT_QUEUE_PREFETCH;
public static final int DEFAULT_DURABLE_TOPIC_PREFETCH = DEFAULT_QUEUE_PREFETCH;
public static final int DEFAULT_TOPIC_PREFETCH = DEFAULT_QUEUE_PREFETCH;
private static final Logger LOG = LoggerFactory.getLogger(JmsDefaultPrefetchPolicy.class);
private int queuePrefetch;
private int queueBrowserPrefetch;
private int topicPrefetch;
private int durableTopicPrefetch;
private int maxPrefetchSize = MAX_PREFETCH_SIZE;
/**
* Initialize default prefetch policies
*/
public JmsDefaultPrefetchPolicy() {
this.queuePrefetch = DEFAULT_QUEUE_PREFETCH;
this.queueBrowserPrefetch = DEFAULT_QUEUE_BROWSER_PREFETCH;
this.topicPrefetch = DEFAULT_TOPIC_PREFETCH;
this.durableTopicPrefetch = DEFAULT_DURABLE_TOPIC_PREFETCH;
}
/**
* Creates a new JmsPrefetchPolicy instance copied from the source policy.
*
* @param source
* The policy instance to copy values from.
*/
public JmsDefaultPrefetchPolicy(JmsDefaultPrefetchPolicy source) {
this.queuePrefetch = source.getQueuePrefetch();
this.queueBrowserPrefetch = source.getQueueBrowserPrefetch();
this.topicPrefetch = source.getTopicPrefetch();
this.durableTopicPrefetch = source.getDurableTopicPrefetch();
this.maxPrefetchSize = source.getMaxPrefetchSize();
}
@Override
public JmsDefaultPrefetchPolicy copy() {
return new JmsDefaultPrefetchPolicy(this);
}
@Override
public int getConfiguredPrefetch(JmsSession session, JmsDestination destination, boolean durable, boolean browser) {
int prefetch = 0;
if (destination.isTopic()) {
if (durable) {
prefetch = getDurableTopicPrefetch();
} else {
prefetch = getTopicPrefetch();
}
} else {
if (browser) {
prefetch = getQueueBrowserPrefetch();
} else {
prefetch = getQueuePrefetch();
}
}
return prefetch;
}
/**
* @return Returns the durableTopicPrefetch.
*/
public int getDurableTopicPrefetch() {
return durableTopicPrefetch;
}
/**
* Sets the durable topic prefetch value, this value is limited by the max
* prefetch size setting.
*
* @param durableTopicPrefetch
* The durableTopicPrefetch to set.
*/
public void setDurableTopicPrefetch(int durableTopicPrefetch) {
this.durableTopicPrefetch = getMaxPrefetchLimit(durableTopicPrefetch);
}
/**
* @return Returns the queuePrefetch.
*/
public int getQueuePrefetch() {
return queuePrefetch;
}
/**
* @param queuePrefetch
* The queuePrefetch to set.
*/
public void setQueuePrefetch(int queuePrefetch) {
this.queuePrefetch = getMaxPrefetchLimit(queuePrefetch);
}
/**
* @return Returns the queueBrowserPrefetch.
*/
public int getQueueBrowserPrefetch() {
return queueBrowserPrefetch;
}
/**
* @param queueBrowserPrefetch
* The queueBrowserPrefetch to set.
*/
public void setQueueBrowserPrefetch(int queueBrowserPrefetch) {
this.queueBrowserPrefetch = getMaxPrefetchLimit(queueBrowserPrefetch);
}
/**
* @return Returns the topicPrefetch.
*/
public int getTopicPrefetch() {
return topicPrefetch;
}
/**
* @param topicPrefetch
* The topicPrefetch to set.
*/
public void setTopicPrefetch(int topicPrefetch) {
this.topicPrefetch = getMaxPrefetchLimit(topicPrefetch);
}
/**
* Gets the currently configured max prefetch size value.
* @return the currently configured max prefetch value.
*/
public int getMaxPrefetchSize() {
return maxPrefetchSize;
}
/**
* Sets the maximum prefetch size value.
*
* @param maxPrefetchSize
* The maximum allowed value for any of the prefetch size options.
*/
public void setMaxPrefetchSize(int maxPrefetchSize) {
this.maxPrefetchSize = maxPrefetchSize;
}
/**
* Sets the prefetch values for all options in this policy to the set limit. If the value
* given is larger than the max prefetch value of this policy the new limit will be capped
* at the max prefetch value.
*
* @param prefetch
* The prefetch value to apply to all prefetch limits.
*/
public void setAll(int prefetch) {
this.durableTopicPrefetch = getMaxPrefetchLimit(prefetch);
this.queueBrowserPrefetch = getMaxPrefetchLimit(prefetch);
this.queuePrefetch = getMaxPrefetchLimit(prefetch);
this.topicPrefetch = getMaxPrefetchLimit(prefetch);
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + durableTopicPrefetch;
result = prime * result + maxPrefetchSize;
result = prime * result + queueBrowserPrefetch;
result = prime * result + queuePrefetch;
result = prime * result + topicPrefetch;
return result;
}
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
JmsDefaultPrefetchPolicy other = (JmsDefaultPrefetchPolicy) obj;
return this.queuePrefetch == other.queuePrefetch &&
this.queueBrowserPrefetch == other.queueBrowserPrefetch &&
this.topicPrefetch == other.topicPrefetch &&
this.durableTopicPrefetch == other.durableTopicPrefetch;
}
private int getMaxPrefetchLimit(int value) {
int result = Math.min(value, maxPrefetchSize);
if (result < value) {
LOG.warn("maximum prefetch limit has been reset from " + value + " to " + MAX_PREFETCH_SIZE);
}
return result;
}
}