ActiveMQ example source code file (LastImageSubscriptionRecoveryPolicy.java)

This example ActiveMQ source code file (LastImageSubscriptionRecoveryPolicy.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - ActiveMQ tags/keywords

arraylist, destinationfilter, exception, exception, lastimagesubscriptionrecoverypolicy, lastimagesubscriptionrecoverypolicy, list, message, messagereference, messagereference, subscriptionrecovery, subscriptionrecoverypolicy, subscriptionrecoverypolicy, topic, util

The ActiveMQ LastImageSubscriptionRecoveryPolicy.java source code

/**
 * 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.util.ArrayList;
import java.util.List;
import org.apache.activemq.broker.Broker;
import org.apache.activemq.broker.ConnectionContext;
import org.apache.activemq.broker.region.MessageReference;
import org.apache.activemq.broker.region.SubscriptionRecovery;
import org.apache.activemq.broker.region.Topic;
import org.apache.activemq.command.ActiveMQDestination;
import org.apache.activemq.command.Message;
import org.apache.activemq.filter.DestinationFilter;

/**
 * This implementation of {@link SubscriptionRecoveryPolicy} will only keep the
 * last message.
 * 
 * @org.apache.xbean.XBean
 * 
 */
public class LastImageSubscriptionRecoveryPolicy implements SubscriptionRecoveryPolicy {

    private volatile MessageReference lastImage;

    public boolean add(ConnectionContext context, MessageReference node) throws Exception {
        lastImage = node;
        return true;
    }

    public void recover(ConnectionContext context, Topic topic, SubscriptionRecovery sub) throws Exception {
        // Re-dispatch the last message seen.
        MessageReference node = lastImage;
        if (node != null) {
            sub.addRecoveredMessage(context, node);
        }
    }

    public void start() throws Exception {
    }

    public void stop() throws Exception {
    }

    public Message[] browse(ActiveMQDestination destination) throws Exception {
        List<Message> result = new ArrayList();
        DestinationFilter filter = DestinationFilter.parseFilter(destination);
        if (filter.matches(lastImage.getMessage().getDestination())) {
            result.add(lastImage.getMessage());
        }
        return result.toArray(new Message[result.size()]);
    }

    public SubscriptionRecoveryPolicy copy() {
        return new LastImageSubscriptionRecoveryPolicy();
    }
    
    public void setBroker(Broker broker) {        
    }

}