threadpool.java

定时器开源项目, 相对于 jcrontab, Quartz 算是更完整的一个项目, 随著开发的版本上来, 他已经脱离只是写在程序里面的计时器, 在指定的时间或区间, 处理所指定的事件. 也加入了 se

/*
 * Copyright James House (c) 2001-2004
 * 
 * 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.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 THE AUTHOR OR 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.
 *  
 */
package org.quartz.spi;

import org.quartz.SchedulerConfigException;

/**
 * <p>
 * The interface to be implemented by classes that want to provide a thread
 * pool for the <code>{@link org.quartz.core.QuartzScheduler}</code>'s use.
 * </p>
 * 
 * @see org.quartz.core.QuartzScheduler
 * 
 * @author James House
 */
public interface ThreadPool {

    /*
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     * 
     * Interface.
     * 
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     */

    /**
     * <p>
     * Execute the given <code>{@link java.lang.Runnable}</code> in the next
     * available <code>Thread</code>.
     * </p>
     * 
     * <p>
     * The implementation of this interface should not throw exceptions unless
     * there is a serious problem (i.e. a serious misconfiguration). If there
     * are no available threads, rather it should either queue the Runnable, or
     * block until a thread is available, depending on the desired strategy.
     * </p>
     */
    public boolean runInThread(Runnable runnable);

    /**
     * <p>
     * Called by the QuartzScheduler before the <code>ThreadPool</code> is
     * used, in order to give the it a chance to initialize.
     * </p>
     */
    public void initialize() throws SchedulerConfigException;

    /**
     * <p>
     * Called by the QuartzScheduler to inform the <code>ThreadPool</code>
     * that it should free up all of it's resources because the scheduler is
     * shutting down.
     * </p>
     */
    public void shutdown(boolean waitForJobsToComplete);

    public int getPoolSize();
}