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ActiveMQ example source code file (DiscardingDLQBroker.java)

This example ActiveMQ source code file (DiscardingDLQBroker.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

activemqdestination, brokerfilter, brokerfilter, discarding, discardingdlqbroker, discardingdlqbroker, dlq, logger, messagereference, messagereference, override, pattern, regex, string, string

The ActiveMQ DiscardingDLQBroker.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.plugin;

import java.util.regex.Pattern;
import org.apache.activemq.broker.Broker;
import org.apache.activemq.broker.BrokerFilter;
import org.apache.activemq.broker.ConnectionContext;
import org.apache.activemq.broker.region.MessageReference;
import org.apache.activemq.broker.region.Subscription;
import org.apache.activemq.command.ActiveMQDestination;
import org.apache.activemq.command.Message;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

/**
 * @author Filip Hanik
 * @version 1.0
 */
public class DiscardingDLQBroker extends BrokerFilter {
    public static Logger log = LoggerFactory.getLogger(DiscardingDLQBroker.class);
    private boolean dropTemporaryTopics = true;
    private boolean dropTemporaryQueues = true;
    private boolean dropAll = true;
    private Pattern[] destFilter;
    private int reportInterval = 1000;
    private long dropCount = 0;

    public DiscardingDLQBroker(Broker next) {
        super(next);
    }

    @Override
    public void sendToDeadLetterQueue(ConnectionContext ctx, MessageReference msgRef,
                                      Subscription subscription) {
        if (log.isTraceEnabled()) {
            log.trace("Discarding DLQ BrokerFilter[pass through] - skipping message:" + (msgRef != null ? msgRef.getMessage() : null));
        }
        boolean dropped = true;
        Message msg = null;
        ActiveMQDestination dest = null;
        String destName = null;
        msg = msgRef.getMessage();
        dest = msg.getDestination();
        destName = dest.getPhysicalName();

        if (dest == null || destName == null ) {
            //do nothing, no need to forward it
            skipMessage("NULL DESTINATION",msgRef);
        } else if (dropAll) {
            //do nothing
            skipMessage("dropAll",msgRef);
        } else if (dropTemporaryTopics && dest.isTemporary() && dest.isTopic()) {
            //do nothing
            skipMessage("dropTemporaryTopics",msgRef);
        } else if (dropTemporaryQueues && dest.isTemporary() && dest.isQueue()) {
            //do nothing
            skipMessage("dropTemporaryQueues",msgRef);
        } else if (destFilter!=null && matches(destName)) {
            //do nothing
            skipMessage("dropOnly",msgRef);
        } else {
            dropped = false;
            next.sendToDeadLetterQueue(ctx, msgRef, subscription);
        }
        if (dropped && getReportInterval()>0) {
            if ((++dropCount)%getReportInterval() == 0 ) {
                log.info("Total of "+dropCount+" messages were discarded, since their destination was the dead letter queue");
            }
        }
    }

    public boolean matches(String destName) {
        for (int i=0; destFilter!=null && i<destFilter.length; i++) {
            if (destFilter[i]!=null && destFilter[i].matcher(destName).matches()) {
                return true;
            }
        }
        return false;
    }

    private void skipMessage(String prefix, MessageReference msgRef) {
        if (log.isDebugEnabled()) {
            String lmsg = "Discarding DLQ BrokerFilter["+prefix+"] - skipping message:" + (msgRef!=null?msgRef.getMessage():null);
            log.debug(lmsg);
        }
    }

    public void setDropTemporaryTopics(boolean dropTemporaryTopics) {
        this.dropTemporaryTopics = dropTemporaryTopics;
    }

    public void setDropTemporaryQueues(boolean dropTemporaryQueues) {
        this.dropTemporaryQueues = dropTemporaryQueues;
    }

    public void setDropAll(boolean dropAll) {
        this.dropAll = dropAll;
    }

    public void setDestFilter(Pattern[] destFilter) {
        this.destFilter = destFilter;
    }

    public void setReportInterval(int reportInterval) {
        this.reportInterval = reportInterval;
    }

    public boolean isDropTemporaryTopics() {
        return dropTemporaryTopics;
    }

    public boolean isDropTemporaryQueues() {
        return dropTemporaryQueues;
    }

    public boolean isDropAll() {
        return dropAll;
    }

    public Pattern[] getDestFilter() {
        return destFilter;
    }

    public int getReportInterval() {
        return reportInterval;
    }

}

Other ActiveMQ examples (source code examples)

Here is a short list of links related to this ActiveMQ DiscardingDLQBroker.java source code file:

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