/hudson-core/src/main/java/hudson/model/PeriodicWork.java
http://github.com/hudson/hudson · Java · 91 lines · 22 code · 7 blank · 62 comment · 0 complexity · a7130b67075945c7bf875e8d2d3f16fd MD5 · raw file
- /*
- * The MIT License
- *
- * Copyright (c) 2004-2009, Sun Microsystems, Inc., Kohsuke Kawaguchi
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
- package hudson.model;
- import hudson.triggers.SafeTimerTask;
- import hudson.triggers.Trigger;
- import hudson.ExtensionPoint;
- import hudson.Extension;
- import hudson.ExtensionList;
- import java.util.logging.Logger;
- import java.util.Random;
- import java.util.Timer;
- /**
- * Extension point to perform a periodic task in Hudson (through {@link Timer}.)
- *
- * <p>
- * This extension point is useful if your plugin needs to perform some work in the background periodically
- * (for example, monitoring, batch processing, garbage collection, etc.)
- *
- * <p>
- * Put {@link Extension} on your class to have it picked up and registered automatically, or
- * manually insert this to {@link Trigger#timer}.
- *
- * <p>
- * This class is designed to run a short task. Implementations whose periodic work takes a long time
- * to run should extend from {@link AsyncPeriodicWork} instead.
- *
- * @author Kohsuke Kawaguchi
- * @see AsyncPeriodicWork
- */
- public abstract class PeriodicWork extends SafeTimerTask implements ExtensionPoint {
- protected final Logger logger = Logger.getLogger(getClass().getName());
- /**
- * Gets the number of milliseconds between successive executions.
- *
- * <p>
- * Hudson calls this method once to set up a recurring timer, instead of
- * calling this each time after the previous execution completed. So this class cannot be
- * used to implement a non-regular recurring timer.
- *
- * <p>
- * IOW, the method should always return the same value.
- */
- public abstract long getRecurrencePeriod();
- /**
- * Gets the number of milliseconds til the first execution.
- *
- * <p>
- * By default it chooses the value randomly between 0 and {@link #getRecurrencePeriod()}
- */
- public long getInitialDelay() {
- return Math.abs(new Random().nextLong())%getRecurrencePeriod();
- }
- /**
- * Returns all the registered {@link PeriodicWork}s.
- */
- public static ExtensionList<PeriodicWork> all() {
- return Hudson.getInstance().getExtensionList(PeriodicWork.class);
- }
- // time constants
- protected static final long MIN = 1000*60;
- protected static final long HOUR =60*MIN;
- protected static final long DAY = 24*HOUR;
- }