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Gemini is a web framework created by TechEmpower.
/*******************************************************************************
* Copyright (c) 2018, TechEmpower, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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.
* * Neither the name TechEmpower, Inc. nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS 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 TECHEMPOWER, INC. 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.
*******************************************************************************/
package com.techempower.gemini.event;
import java.util.*;
import com.techempower.gemini.*;
import com.techempower.helper.*;
import com.techempower.log.*;
import com.techempower.scheduler.*;
import com.techempower.util.*;
/**
* Does nothing; for testing/demonstration purposes only. Typical usage for
* events is to instantiate and schedule events in the "start" method of
* the Infrastructure subclass. E.g.,
*
* public void start()
* {
* getScheduler().clear();
* getScheduler().scheduleEvent(new NoOpEvent(this.application));
* }
*/
public class NoOpEvent
extends ScheduledEvent
implements Configurable
{
//
// Constants.
//
public static final String LOCAL_COMPONENT_CODE = "nevt";
//
// Member variables.
//
private final GeminiApplication application;
private final ComponentLog log;
//
// Member methods.
//
/**
* Constructor.
*/
public NoOpEvent(GeminiApplication application)
{
super("No operation / Testing",
"Executes for 30 seconds but does nothing; safe for testing");
// Get local references set up.
this.application = application;
this.log = application.getLog(LOCAL_COMPONENT_CODE);
// Get configured.
this.application.getConfigurator().addConfigurable(this);
}
/**
* Configures this component.
*/
@Override
public void configure(EnhancedProperties props)
{
// Sometimes the time of day for an event is configurable, so events
// commonly implement the Configurable interface.
// In this demonstration, however, we are doing nothing.
}
/**
* Gets the initial/default scheduled time for the first run of this
* event.
*/
@Override
public long getDefaultScheduledTime()
{
// Get a current-time SimpleDate.
Calendar nextRun = DateHelper.getCalendarInstance();
// In this example, we're going to specify an initial execution of
// 12:30pm. We can't just set the hour to 12 because we may be
// starting up after that time, so we'll just add hours until we get
// to 12:30pm. This is a rough calculation, but good enough.
// Find 12pm.
nextRun.add(Calendar.HOUR_OF_DAY, 1);
while (nextRun.get(Calendar.HOUR_OF_DAY) != 12)
{
nextRun.add(Calendar.HOUR_OF_DAY, 1);
}
// Set the minutes and seconds accordingly.
nextRun.set(Calendar.MINUTE, 30);
nextRun.set(Calendar.SECOND, 0);
// Return the time.
return nextRun.getTimeInMillis();
}
/**
* Overload this method to return true if this event needs to be run
* on a thread separate from the Scheduler itself. By default, events
* get run ON the scheduler thread.
*/
@Override
public boolean requiresOwnThread()
{
// Let's get a separate thread.
return true;
}
/**
* Executes this event.
*
* @param scheduler A reference to the scheduler so that we can reschedule
* this event after execution is complete.
* @param onDemandExecute true if an administrator has requested an on-
* demand execution of this event; false if the event is running
* according to its schedule.
*/
@Override
public void execute(Scheduler scheduler, boolean onDemandExecute)
{
// We wrap the actual work in a try/catch block so that even if the
// run is interrupted by an uncaught exception, we'll reschedule
// properly.
try
{
// Call our example do-nothing method.
doNothing();
}
catch (Exception exc)
{
this.log.log("Exception: " + exc);
}
// Log the event completion.
this.log.log(this + " complete.");
// If this execution was a scheduled execution, let's reschedule for
// the same time, but one day later.
if (!onDemandExecute)
{
// Reschedule this event.
Calendar newEventTime = DateHelper.getCalendarInstance(getScheduledTime());
// Add a day.
newEventTime.add(Calendar.DATE, 1);
// Tell the scheduler to reschedule.
scheduler.scheduleEvent(this, newEventTime.getTime());
}
}
/**
* Does nothing; this is a no-op event.
*/
public void doNothing()
{
this.log.log("Doing nothing; this is a no-op event.");
}
/**
* Standard toString.
*/
@Override
public String toString()
{
return "[NoOpEvent: " + getScheduledTime() + "]";
}
} // End NoOpEvent.