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.store; 018 019 import java.io.IOException; 020 import org.apache.activemq.broker.ConnectionContext; 021 import org.apache.activemq.command.ActiveMQDestination; 022 import org.apache.activemq.command.MessageId; 023 import org.apache.activemq.usage.MemoryUsage; 024 025 abstract public class AbstractMessageStore implements MessageStore { 026 protected final ActiveMQDestination destination; 027 028 public AbstractMessageStore(ActiveMQDestination destination) { 029 this.destination = destination; 030 } 031 032 public void dispose(ConnectionContext context) { 033 } 034 035 public void start() throws Exception { 036 } 037 038 public void stop() throws Exception { 039 } 040 041 public ActiveMQDestination getDestination() { 042 return destination; 043 } 044 045 public void setMemoryUsage(MemoryUsage memoryUsage) { 046 } 047 048 public void setBatch(MessageId messageId) throws IOException, Exception { 049 } 050 051 /** 052 * flag to indicate if the store is empty 053 * @return true if the message count is 0 054 * @throws Exception 055 */ 056 public boolean isEmpty() throws Exception{ 057 return getMessageCount()==0; 058 } 059 }