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//
// Copyright 2001 iPlanet/ Sun Microsystems, Inc. All Rights Reserved.
//
// Author : darpan
// Module : Utils
//
package com.sun.enterprise.util.scheduler;

/**
* PeriodicallyServicable inherits from the <I>Servicable</I> interface and
* enable utilities such as PeriodicEventScheduler to give a callback to the
* objects on their service methods.<br>
* Ensure that the objects implementing PeriodicallyServicable do not hog the
* threads for execution. Logic like inserting a task onto the writer thread
* queues is best suited for this purpose.
* <BR> <I>$Source: /cvs/glassfish/appserv-commons/src/java/com/sun/enterprise/util/scheduler/PeriodicallyServicable.java,v $</I>
* @author     $Author: tcfujii $
* @version    1.0 $Revision: 1.4 $ $Date: 2007/05/05 05:32:17 $
* @see com.sun.enterprise.util.threadpool.Servicable
* @see PeriodicEventScheduler
*/
public interface PeriodicallyServicable
    extends com.sun.enterprise.util.threadpool.Servicable
{
    /**
    * Get the frequency (time interval) at which service() method will be invoked.
    * @return time in milli seconds.
    */
    public long getFrequency();
    
    /**
    * Determine to execute the service method of this object even if it has 
    * missed the right schedule.
    */
    public boolean getExecuteIfMissed();
    
    /**
    * Determine to execute the service method of this object when the 
    * schedule is delayed by 'missedByMillis' milli seconds.
    */
    public boolean getExecutionTolerance(long missedByMillis);
    
    /**
    * Print an identification for the object.
    */
    public String toString();
}