001/** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.apache.activemq.broker.region.policy; 018 019import org.apache.activemq.broker.region.TopicSubscription; 020 021/** 022 * This PendingMessageLimitStrategy sets the maximum pending message limit value to be 023 * a multiplier of the prefetch limit of the subscription. 024 * 025 * @org.apache.xbean.XBean 026 * 027 * 028 */ 029public class PrefetchRatePendingMessageLimitStrategy implements PendingMessageLimitStrategy { 030 031 private double multiplier = 0.5; 032 033 public int getMaximumPendingMessageLimit(TopicSubscription subscription) { 034 int prefetchSize = subscription.getConsumerInfo().getPrefetchSize(); 035 return (int) (prefetchSize * multiplier); 036 } 037 038 public double getMultiplier() { 039 return multiplier; 040 } 041 042 /** 043 * Sets the multiplier of the prefetch size which will be used to define the maximum number of pending 044 * messages for non-durable topics before messages are discarded. 045 */ 046 public void setMultiplier(double rate) { 047 this.multiplier = rate; 048 } 049 050}