Glassfish example source code file (ConnectorTimerProxy.java)

This example Glassfish source code file (ConnectorTimerProxy.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 - Glassfish tags/keywords

classloader, connectortimerproxy, connectortimerproxy, date, date, log, logger, logging, object, override, override, recreating, timer, timer, util

The Glassfish ConnectorTimerProxy.java source code

/*
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 *
 * Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved.
 *
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
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 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
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 */

package com.sun.enterprise.connectors.util;

import com.sun.enterprise.connectors.ConnectorRuntime;
import com.sun.logging.LogDomains;
import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;
import java.util.logging.Level;
import java.util.logging.Logger;

public class ConnectorTimerProxy extends Timer {
    
    private static ConnectorTimerProxy connectorTimer;
    private Timer timer;
    private final Object getTimerLock = new Object();
    
    private final static Logger _logger = LogDomains.getLogger(ConnectorTimerProxy.class, 
            LogDomains.RSR_LOGGER);

    private ConnectorTimerProxy(boolean isDaemon) {
        super(isDaemon);
    }

    private Timer getTimer() {
        synchronized (getTimerLock) {
            if (timer == null) {
                ClassLoader loader = null;
                try {
                    loader = Thread.currentThread().getContextClassLoader();
                    Thread.currentThread().setContextClassLoader(
                            ConnectorRuntime.getRuntime().getConnectorClassLoader());
                    timer = new Timer("connector-timer-proxy", true);
                } finally {
                    Thread.currentThread().setContextClassLoader(loader);
                }
            }
        }
        return timer;        
    }

    public static final ConnectorTimerProxy getProxy() {
        if (connectorTimer == null) {
             connectorTimer = new ConnectorTimerProxy(true);
        }
        return connectorTimer;
    }
    
    /**
     * Proxy method to schedule a timer task at fixed rate.
     * The unchecked exceptions are caught here and in such cases, the timer
     * is recreated and task is rescheduled.
     * @param task
     * @param delay
     * @param period
     */
    @Override
    public void scheduleAtFixedRate(TimerTask task, long delay, long period) {
        timer = getTimer();
        try {
            timer.scheduleAtFixedRate(task, delay, period);
        } catch(Exception ex) {
            handleTimerException(ex);
            timer.scheduleAtFixedRate(task, delay, period);
        }
    }

    @Override
    public void cancel() {
        timer = getTimer();
        try {
            timer.cancel();
        } catch(Exception ex) {
            _logger.log(Level.WARNING, "exception_cancelling_timer", ex.getMessage());
        }
    }

    @Override
    public int purge() {
        int status = 0;
        timer = getTimer();
        try {
            status = timer.purge();
        } catch(Exception ex) {
            _logger.log(Level.WARNING, "exception_purging_timer",  ex.getMessage());
        }        
        return status;
    }

    /**
     * Proxy method to schedule a timer task after a specified delay.
     * The unchecked exceptions are caught here and in such cases, the timer
     * is recreated and task is rescheduled.
     * @param task
     * @param delay
     * @param period
     */
    @Override
    public void schedule(TimerTask task, long delay) {
        timer = getTimer();
        try {
            timer.schedule(task, delay);
        } catch(Exception ex) {
            handleTimerException(ex);
            timer.schedule(task, delay);
        }
    }

    /**
     * Proxy method to schedule a timer task at the specified time.
     * The unchecked exceptions are caught here and in such cases, the timer
     * is recreated and task is rescheduled.
     * @param task
     * @param delay
     * @param period
     */    
    @Override
    public void schedule(TimerTask task, Date time) {
        timer = getTimer();
        try {
            timer.schedule(task, time);
        } catch(Exception ex) {
            handleTimerException(ex);
            timer.schedule(task, time);
        }        
    }

    /**
     * Proxy method to schedule a timer task for repeated fixed-delay execution, 
     * beginning after the specified delay.
     * The unchecked exceptions are caught here and in such cases, the timer
     * is recreated and task is rescheduled.
     * @param task
     * @param delay
     * @param period
     */
    @Override
    public void schedule(TimerTask task, long delay, long period) {
        timer = getTimer();
        try {
            timer.schedule(task, delay, period);
        } catch(Exception ex) {
            handleTimerException(ex);
            timer.schedule(task, delay, period);
        }        
    }

    /**
     * Proxy method to schedule a timer task for repeated fixed-delay execution, 
     * beginning after the specified delay.
     * The unchecked exceptions are caught here and in such cases, the timer
     * is recreated and task is rescheduled.
     * @param task
     * @param delay
     * @param period
     */
    @Override
    public void schedule(TimerTask task, Date firstTime, long period) {
        timer = getTimer();
        try {
            timer.schedule(task, firstTime, period);
        } catch(Exception ex) {
            handleTimerException(ex);
            timer.schedule(task, firstTime, period);
        }        
    }

    /**
     * Proxy method to schedule a timer task for repeated fixed-rate execution, 
     * beginning after the specified delay.
     * The unchecked exceptions are caught here and in such cases, the timer
     * is recreated and task is rescheduled.
     * @param task
     * @param delay
     * @param period
     */
    @Override
    public void scheduleAtFixedRate(TimerTask task, Date firstTime, long period) {
        timer = getTimer();
        try {
            timer.scheduleAtFixedRate(task, firstTime, period);
        } catch(Exception ex) {
            handleTimerException(ex);
            timer.scheduleAtFixedRate(task, firstTime, period);
        }        
    }

    /**
     * Handle any exception occured during scheduling timer. 
     * 
     * In case of unchecked exceptions, the timer is recreated to be used 
     * by the subsequent requests for scheduling.
     * @param ex exception that was caught
     */
    private void handleTimerException(Exception ex) {
        _logger.log(Level.WARNING, "exception_scheduling_timer", ex.getMessage());
        
        //In case of unchecked exceptions, timer needs to recreated.
        _logger.info("Recreating Timer and scheduling at fixed rate");
        timer = null;
        timer = getTimer();
    }
}