org.apache.activemq.broker.region.policy.OldestMessageWithLowestPriorityEvictionStrategy Maven / Gradle / Ivy
/**
* 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.activemq.broker.region.policy;
import java.io.IOException;
import java.util.Iterator;
import java.util.LinkedList;
import org.apache.activemq.broker.region.MessageReference;
/**
* An eviction strategy which evicts the oldest message with the lowest priority first.
*
* @org.apache.xbean.XBean
*
* messageEvictionStrategy
*/
public class OldestMessageWithLowestPriorityEvictionStrategy extends MessageEvictionStrategySupport {
public MessageReference[] evictMessages(LinkedList messages) throws IOException {
byte lowestPriority = Byte.MAX_VALUE;
int pivot = 0;
Iterator iter = messages.iterator();
for (int i = 0; iter.hasNext(); i++) {
MessageReference reference = (MessageReference) iter.next();
byte priority = reference.getMessage().getPriority();
if (priority < lowestPriority) {
lowestPriority = priority;
pivot = i;
}
}
return new MessageReference[] {(MessageReference) messages.remove(pivot)};
}
}