| package org.apache.turbine.services.schedule; |
| |
| /* ==================================================================== |
| * The Apache Software License, Version 1.1 |
| * |
| * Copyright (c) 2001-2003 The Apache Software Foundation. All rights |
| * reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. The end-user documentation included with the redistribution, |
| * if any, must include the following acknowledgment: |
| * "This product includes software developed by the |
| * Apache Software Foundation (http://www.apache.org/)." |
| * Alternately, this acknowledgment may appear in the software itself, |
| * if and wherever such third-party acknowledgments normally appear. |
| * |
| * 4. The names "Apache" and "Apache Software Foundation" and |
| * "Apache Turbine" must not be used to endorse or promote products |
| * derived from this software without prior written permission. For |
| * written permission, please contact apache@apache.org. |
| * |
| * 5. Products derived from this software may not be called "Apache", |
| * "Apache Turbine", nor may "Apache" appear in their name, without |
| * prior written permission of the Apache Software Foundation. |
| * |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation. For more |
| * information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| */ |
| |
| import java.util.Collections; |
| import java.util.Comparator; |
| import java.util.List; |
| import java.util.Vector; |
| |
| import org.apache.turbine.util.TurbineException; |
| |
| /** |
| * Queue for the scheduler. |
| * |
| * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a> |
| * @author <a href="mailto:quintonm@bellsouth.net">Quinton McCombs</a> |
| * @version $Id$ |
| */ |
| public class JobQueue |
| { |
| /** |
| * The queue of <code>JobEntry</code> objects. |
| */ |
| private Vector queue = null; |
| |
| /** |
| * Creates a new instance. |
| */ |
| public JobQueue() |
| { |
| queue = new Vector(10); |
| } |
| |
| /** |
| * Return the next job off the top of the queue, or <code>null</code> if |
| * there are no jobs in the queue. |
| * |
| * @return The next job in the queue. |
| */ |
| public JobEntry getNext() |
| { |
| if (queue.size() > 0) |
| { |
| return (JobEntry) queue.elementAt(0); |
| } |
| else |
| { |
| return null; |
| } |
| } |
| |
| /** |
| * Return a specific job. |
| * |
| * @param je The JobEntry we are looking for. |
| * @return A JobEntry. |
| */ |
| public JobEntry getJob(JobEntry je) |
| { |
| int index = -1; |
| |
| if (je != null) |
| { |
| index = queue.indexOf(je); |
| } |
| |
| if (index < 0) |
| { |
| return null; |
| } |
| else |
| { |
| return (JobEntry) queue.elementAt(index); |
| } |
| } |
| |
| /** |
| * List jobs in the queue. This is used by the scheduler UI. |
| * |
| * @return A Vector of <code>JobEntry</code> objects. |
| */ |
| public Vector list() |
| { |
| if (queue != null && queue.size() > 0) |
| { |
| return (Vector) queue.clone(); |
| } |
| else |
| { |
| return null; |
| } |
| } |
| |
| /** |
| * Add a job to the queue. |
| * |
| * @param je A JobEntry job. |
| */ |
| public synchronized void add(JobEntry je) |
| { |
| queue.addElement(je); |
| sortQueue(); |
| } |
| |
| /** |
| * Batch load jobs. Retains any already enqueued jobs. Called on |
| * <code>SchedulerService</code> start-up. |
| * |
| * @param jobEntries A list of the <code>JobEntry</code> objects to load. |
| */ |
| public synchronized void batchLoad(List jobEntries) |
| { |
| if (jobEntries != null) |
| { |
| queue.addAll(jobEntries); |
| sortQueue(); |
| } |
| |
| } |
| |
| /** |
| * Remove a job from the queue. |
| * |
| * @param je A JobEntry with the job to remove. |
| */ |
| public synchronized void remove(JobEntry je) |
| { |
| queue.removeElement(je); |
| sortQueue(); |
| } |
| |
| /** |
| * Modify a job on the queue. |
| * |
| * @param je A JobEntry with the job to modify |
| */ |
| public synchronized void modify(JobEntry je) |
| throws TurbineException |
| { |
| remove(je); |
| je.calcRunTime(); |
| this.add(je); |
| sortQueue(); |
| } |
| |
| /** |
| * Update the job for its next run time. |
| * |
| * @param je A JobEntry to be updated. |
| * @exception TurbineException a generic exception. |
| */ |
| public synchronized void updateQueue(JobEntry je) |
| throws TurbineException |
| { |
| je.calcRunTime(); |
| sortQueue(); |
| } |
| |
| /** |
| * Re-sort the existing queue. Consumers of this method should be |
| * <code>synchronized</code>. |
| */ |
| private void sortQueue() |
| { |
| Comparator aComparator = new Comparator() |
| { |
| public int compare(Object o1, Object o2) |
| { |
| Long time1 = new Long(((JobEntry) o1).getNextRuntime()); |
| Long time2 = new Long(((JobEntry) o2).getNextRuntime()); |
| return (time1.compareTo(time2)); |
| } |
| }; |
| |
| Collections.sort(queue, aComparator); |
| } |
| } |