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 */ 017 package org.apache.activemq.broker.region.policy; 018 019 import org.apache.activemq.broker.Broker; 020 import org.apache.activemq.broker.region.DurableTopicSubscription; 021 import org.apache.activemq.broker.region.Subscription; 022 import org.apache.activemq.broker.region.cursors.PendingMessageCursor; 023 import org.apache.activemq.broker.region.cursors.StoreDurableSubscriberCursor; 024 import org.apache.activemq.kaha.Store; 025 026 /** 027 * Creates a PendingMessageCursor that access the persistent store to retrieve 028 * messages 029 * 030 * @org.apache.xbean.XBean element="storeDurableSubscriberCursor" 031 * description="Pending messages for a durable 032 * subscriber are referenced from the Store" 033 * 034 */ 035 public class StorePendingDurableSubscriberMessageStoragePolicy implements PendingDurableSubscriberMessageStoragePolicy { 036 boolean immediatePriorityDispatch = true; 037 boolean useCache = true; 038 039 public boolean isImmediatePriorityDispatch() { 040 return immediatePriorityDispatch; 041 } 042 043 /** 044 * Ensure that new higher priority messages will get an immediate dispatch 045 * rather than wait for the end of the current cursor batch. 046 * Useful when there is a large message backlog and intermittent high priority messages. 047 * 048 * @param immediatePriorityDispatch 049 */ 050 public void setImmediatePriorityDispatch(boolean immediatePriorityDispatch) { 051 this.immediatePriorityDispatch = immediatePriorityDispatch; 052 } 053 054 public boolean isUseCache() { 055 return useCache; 056 } 057 058 public void setUseCache(boolean useCache) { 059 this.useCache = useCache; 060 } 061 062 /** 063 * Retrieve the configured pending message storage cursor; 064 * @param broker 065 * 066 * @param clientId 067 * @param name 068 * @param maxBatchSize 069 * @param sub 070 * @return the Pending Message cursor 071 */ 072 public PendingMessageCursor getSubscriberPendingMessageCursor(Broker broker,String clientId, String name, int maxBatchSize, DurableTopicSubscription sub) { 073 StoreDurableSubscriberCursor cursor = new StoreDurableSubscriberCursor(broker,clientId, name, maxBatchSize, sub); 074 cursor.setUseCache(isUseCache()); 075 cursor.setImmediatePriorityDispatch(isImmediatePriorityDispatch()); 076 return cursor; 077 } 078 }