QueueReaperBean.java

/*
 * JBoss, Home of Professional Open Source
 * Copyright 2008, Red Hat, Inc., and others contributors as indicated
 * by the @authors tag. All rights reserved.
 * See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 * This copyrighted material is made available to anyone wishing to use,
 * modify, copy, or redistribute it subject to the terms and conditions
 * of the GNU Lesser General Public License, v. 2.1.
 * This program is distributed in the hope that it will be useful, but WITHOUT A
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
 * You should have received a copy of the GNU Lesser General Public License,
 * v.2.1 along with this distribution; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA  02110-1301, USA.
 */
package org.jboss.narayana.blacktie.administration;

import java.io.IOException;
import java.util.Properties;

import javax.management.AttributeNotFoundException;
import javax.management.InstanceNotFoundException;
import javax.management.MBeanException;
import javax.management.MBeanServer;
import javax.management.MalformedObjectNameException;
import javax.management.ObjectInstance;
import javax.management.ObjectName;
import javax.management.ReflectionException;
import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import javax.annotation.Resource;
import javax.ejb.Singleton;
import javax.ejb.Startup;
import javax.ejb.Timeout;
import javax.ejb.Timer;
import javax.ejb.TimerService;
import javax.ejb.TimerConfig;
import javax.ejb.NoSuchObjectLocalException;

import org.apache.log4j.LogManager;
import org.apache.log4j.Logger;
import org.jboss.narayana.blacktie.jatmibroker.core.conf.ConfigurationException;
import org.jboss.narayana.blacktie.jatmibroker.core.conf.XMLParser;

@Singleton
@Startup
public class QueueReaperBean {
    /** logger */
    private static final Logger log = LogManager.getLogger(QueueReaperBean.class);

    /** Interval at which to run */
    private long interval = -1;

    private Properties prop;

    private MBeanServer beanServerConnection;

    @Resource
    private TimerService timerService;

    public QueueReaperBean() {
        beanServerConnection = java.lang.management.ManagementFactory.getPlatformMBeanServer();
    }

    @PostConstruct
    public void start() {
        log.info("QueueReaper Started");

        try {
            prop = new Properties();
            XMLParser.loadProperties("btconfig.xsd", "btconfig.xml", prop);
            this.interval = Integer.parseInt(prop.getProperty("QueueReaperInterval", "30")) * 1000;

            timerService.createIntervalTimer(interval, interval, new TimerConfig("queue reaper", false));
            log.info("QueueReaper create timer with " + interval + "ms");
	} catch (ConfigurationException e) {
            log.error("btconfig.xml is not valid: " + e);
	} 
    }

    @PreDestroy
    public void stop() {
        log.info("QueueReaper stopped");
    }

    @Timeout
    public void run(Timer timer) {
        try {
            log.trace("QueueReaper Running: timer is " + timer.getInfo());
            ObjectName objName = new ObjectName("jboss.as:subsystem=messaging,hornetq-server=default,jms-queue=*");
            ObjectInstance[] dests = beanServerConnection.queryMBeans(objName, null).toArray(new ObjectInstance[] {});

            for (int i = 0; i < dests.length; i++) {
                String serviceComponentOfObjectName = dests[i].getObjectName().getCanonicalName();
                serviceComponentOfObjectName = serviceComponentOfObjectName.substring(
                        serviceComponentOfObjectName.indexOf('_') + 1,
                        serviceComponentOfObjectName.indexOf(",", serviceComponentOfObjectName.indexOf('_')));
                log.trace("Service name component of ObjectName is: " + serviceComponentOfObjectName);
                String server = (String) prop.get("blacktie." + serviceComponentOfObjectName + ".server");
                log.trace("Checking for: " + serviceComponentOfObjectName + " " + server + " "
                        + prop.get("blacktie." + serviceComponentOfObjectName + ".externally-managed-destination"));

                if ((serviceComponentOfObjectName.startsWith(".") || ((server != null && !(Boolean) prop.get("blacktie."
                        + serviceComponentOfObjectName + ".externally-managed-destination"))))
                        && consumerCount(serviceComponentOfObjectName) == 0) {
                    log.warn("undeploy service pending for " + serviceComponentOfObjectName
                            + " as consumer count is 0, will check again in " + interval + "ms");
                    long queueReapCheck = System.currentTimeMillis();

                    Thread.sleep(this.interval);   
                    // double check consumer is 0
                    if (BlacktieStompAdministrationService.isOlderThanReapCheck(serviceComponentOfObjectName, queueReapCheck)
                            && consumerCount(serviceComponentOfObjectName) == 0) {
                        BlacktieStompAdministrationService.undeployQueue(serviceComponentOfObjectName);
                        log.warn("undeploy service " + serviceComponentOfObjectName + " for consumer is 0");
                    } else {
                        log.debug("Undeploy not required for: " + serviceComponentOfObjectName + " at: " + server
                                + " as client connected");
                    }
                } else {
                    log.debug("Undeploy not required for: " + serviceComponentOfObjectName + " at: " + server);
                }
            }
	} catch (NoSuchObjectLocalException e) {
	    log.debug("The timer has expired or has been cancelled");
        } catch (InterruptedException e) {
            log.debug("Sleeping interrupted");
        } catch (Exception e) {
            log.error("run ping thread failed with (will wait for: " + interval + " ms): " + e, e);
        }
    }

    int consumerCount(String serviceName) throws MalformedObjectNameException, NullPointerException,
    AttributeNotFoundException, InstanceNotFoundException, ReflectionException, IOException, MBeanException {
        log.trace(serviceName);
        boolean conversational = false;
        String type = "queue";
        if (!serviceName.startsWith(".")) {
            conversational = (Boolean) prop.get("blacktie." + serviceName + ".conversational");
            type = (String) prop.get("blacktie." + serviceName + ".type");
        }
        String prefix = null;
        if (conversational) {
            prefix = "BTC_";
        } else {
            prefix = "BTR_";
        }

        ObjectName objName = new ObjectName("jboss.as:subsystem=messaging,hornetq-server=default,jms-" + type + "=" + prefix
                + serviceName);
        try {
            Integer count = null;
            if (type.equals("queue")) {
                count = (Integer) beanServerConnection.getAttribute(objName, "consumerCount");
            } else {
                count = (Integer) beanServerConnection.getAttribute(objName, "subscriptionCount");
            }
            return count.intValue();
        } catch (javax.management.InstanceNotFoundException e) {
            log.debug("Instance not found: " + objName);
            return -1;
        }
    }
}