Spring Framework example source code file (ScheduledTimerTask.java)

This example Spring Framework source code file (ScheduledTimerTask.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 - Spring Framework tags/keywords

delegatingtimertask, delegatingtimertask, scheduledtimertask, scheduledtimertask, timertask, timertask, util

The Spring Framework ScheduledTimerTask.java source code

/*
 * Copyright 2002-2007 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.scheduling.timer;

import java.util.TimerTask;

/**
 * JavaBean that describes a scheduled {@link TimerTask}, consisting of the
 * {@link TimerTask} itself or a {@link Runnable} to create a {@link TimerTask}
 * for and a delay plus period. The period needs to be specified; there is
 * no point in a default for it.
 *
 * <p>The JDK's {@link java.util.Timer} facility does not offer sophisticated
 * scheduling options such as cron expressions. Consider using Quartz for
 * such advanced needs.
 *
 * <p>Note that the {@link java.util.Timer} mechanism uses a {@link TimerTask}
 * instance that is shared between repeated executions, in contrast to Quartz
 * which creates a new Job instance for each execution.
 *
 * @author Juergen Hoeller
 * @since 19.02.2004
 * @see java.util.TimerTask
 * @see java.util.Timer#schedule(TimerTask, long, long)
 * @see java.util.Timer#scheduleAtFixedRate(TimerTask, long, long)
 */
public class ScheduledTimerTask {

	private TimerTask timerTask;

	private long delay = 0;

	private long period = -1;

	private boolean fixedRate = false;


	/**
	 * Create a new ScheduledTimerTask,
	 * to be populated via bean properties.
	 * @see #setTimerTask
	 * @see #setDelay
	 * @see #setPeriod
	 * @see #setFixedRate
	 */
	public ScheduledTimerTask() {
	}

	/**
	 * Create a new ScheduledTimerTask, with default
	 * one-time execution without delay.
	 * @param timerTask the TimerTask to schedule
	 */
	public ScheduledTimerTask(TimerTask timerTask) {
		this.timerTask = timerTask;
	}

	/**
	 * Create a new ScheduledTimerTask, with default
	 * one-time execution with the given delay.
	 * @param timerTask the TimerTask to schedule
	 * @param delay the delay before starting the task for the first time (ms)
	 */
	public ScheduledTimerTask(TimerTask timerTask, long delay) {
		this.timerTask = timerTask;
		this.delay = delay;
	}

	/**
	 * Create a new ScheduledTimerTask.
	 * @param timerTask the TimerTask to schedule
	 * @param delay the delay before starting the task for the first time (ms)
	 * @param period the period between repeated task executions (ms)
	 * @param fixedRate whether to schedule as fixed-rate execution
	 */
	public ScheduledTimerTask(TimerTask timerTask, long delay, long period, boolean fixedRate) {
		this.timerTask = timerTask;
		this.delay = delay;
		this.period = period;
		this.fixedRate = fixedRate;
	}

	/**
	 * Create a new ScheduledTimerTask, with default
	 * one-time execution without delay.
	 * @param timerTask the Runnable to schedule as TimerTask
	 */
	public ScheduledTimerTask(Runnable timerTask) {
		setRunnable(timerTask);
	}

	/**
	 * Create a new ScheduledTimerTask, with default
	 * one-time execution with the given delay.
	 * @param timerTask the Runnable to schedule as TimerTask
	 * @param delay the delay before starting the task for the first time (ms)
	 */
	public ScheduledTimerTask(Runnable timerTask, long delay) {
		setRunnable(timerTask);
		this.delay = delay;
	}

	/**
	 * Create a new ScheduledTimerTask.
	 * @param timerTask the Runnable to schedule as TimerTask
	 * @param delay the delay before starting the task for the first time (ms)
	 * @param period the period between repeated task executions (ms)
	 * @param fixedRate whether to schedule as fixed-rate execution
	 */
	public ScheduledTimerTask(Runnable timerTask, long delay, long period, boolean fixedRate) {
		setRunnable(timerTask);
		this.delay = delay;
		this.period = period;
		this.fixedRate = fixedRate;
	}


	/**
	 * Set the Runnable to schedule as TimerTask.
	 * @see DelegatingTimerTask
	 */
	public void setRunnable(Runnable timerTask) {
		this.timerTask = new DelegatingTimerTask(timerTask);
	}

	/**
	 * Set the TimerTask to schedule.
	 */
	public void setTimerTask(TimerTask timerTask) {
		this.timerTask = timerTask;
	}

	/**
	 * Return the TimerTask to schedule.
	 */
	public TimerTask getTimerTask() {
		return this.timerTask;
	}

	/**
	 * Set the delay before starting the task for the first time,
	 * in milliseconds. Default is 0, immediately starting the
	 * task after successful scheduling.
	 */
	public void setDelay(long delay) {
		this.delay = delay;
	}

	/**
	 * Return the delay before starting the job for the first time.
	 */
	public long getDelay() {
		return this.delay;
	}

	/**
	 * Set the period between repeated task executions, in milliseconds.
	 * <p>Default is -1, leading to one-time execution. In case of a positive
	 * value, the task will be executed repeatedly, with the given interval
	 * inbetween executions.
	 * <p>Note that the semantics of the period value vary between fixed-rate
	 * and fixed-delay execution.
	 * <p>Note: A period of 0 (for example as fixed delay) is not
	 * supported, simply because <code>java.util.Timer itself does not
	 * support it. Hence a value of 0 will be treated as one-time execution;
	 * however, that value should never be specified explicitly in the first place!
	 * @see #setFixedRate
	 * @see #isOneTimeTask()
	 * @see java.util.Timer#schedule(TimerTask, long, long)
	 */
	public void setPeriod(long period) {
		this.period = period;
	}

	/**
	 * Return the period between repeated task executions.
	 */
	public long getPeriod() {
		return this.period;
	}

	/**
	 * Is this task only ever going to execute once?
	 * @return <code>true if this task is only ever going to execute once
	 * @see #getPeriod()
	 */
	public boolean isOneTimeTask() {
		return (this.period <= 0);
	}

	/**
	 * Set whether to schedule as fixed-rate execution, rather than
	 * fixed-delay execution. Default is "false", that is, fixed delay.
	 * <p>See Timer javadoc for details on those execution modes.
	 * @see java.util.Timer#schedule(TimerTask, long, long)
	 * @see java.util.Timer#scheduleAtFixedRate(TimerTask, long, long)
	 */
	public void setFixedRate(boolean fixedRate) {
		this.fixedRate = fixedRate;
	}

	/**
	 * Return whether to schedule as fixed-rate execution.
	 */
	public boolean isFixedRate() {
		return this.fixedRate;
	}

}