定时启动类[servlet],可同步或异步

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import com.you9.base.WorkQueue;

/**
 * <p>Title: </p>
 * <p>Description: </p>
 * <p>Copyright: Copyright (c) 2006</p>
 * <p>Company: </p>
 * @author not attributable
 * @version 1.0
 */

public class RanksServlet extends HttpServlet
{
    private static final String CONTENT_TYPE = "text/html; charset=UTF-8";

    private boolean isSyn = true;

    //Initialize global variables
    public void init() throws ServletException
    {
        System.out.println("start RanksServlet...");
        super.init();
        RequestTask task = new RequestTask();
        task.start();

    }

    /**
     * 定时启动器
     * <p>Title: </p>
     * <p>Description: </p>
     * <p>Copyright: Copyright (c) 2006</p>
     * <p>Company: </p>
     * @author not attributable
     * @version 1.0
     */
    private class RequestTask extends Thread
    {
        public void run()
        {
            try
            {
                int INIT_SLEEP_INTERVAL = 10 * 1000; //首次启动时睡眠10S后再启动
                int EXEC_INTERVAL = 15 * 60 * 1000; //每15分钟运行一次，更新数据

                sleep(INIT_SLEEP_INTERVAL);

                while (true)
                {
                    syncData();
                    sleep(EXEC_INTERVAL);
                }
            }
            catch (Exception ex4)
            {
                ex4.printStackTrace();
            }
        }

    }

    /**
     * 同步或异步调用更新Ranks的方法
     */
    private void syncData()
    {
        if (isSyn)
        {
            //同步调用
            reload();
        }
        else
        {
            //异步调用
            WorkQueue.getInstance().excute(new LoadRanksData());
        }
    }

    class LoadRanksData implements Runnable
    {
        public void run()
        {
            reload();
        }
    }

    /**
     * 更新ranks的数据
     */
    private void reload()
    {

        int ranksNum = 31;

        for (int i = 0; i <= ranksNum; i++)
        {
            Ranks ranks = RanksFactory.getInstance().getRanks(i);
            ranks.getRanks(null);
        }

    }

    //Clean up resources
    public void destroy()
    {
    }
}