java手写的定时器.

此为转载.

用JAVA写了一个定时器类，此类作为一个线程运行，包含了一个队列存放定时器消息，通过比较定时器的触发时间，俺触发事件先后顺序排列队列。

import java.util.concurrent.*;

import java.util.*;

public class TimerTask implements Runnable {

    /**定时器事件队列*/

    PriorityBlockingQueue<TimerSlot> queue_ =  new PriorityBlockingQueue<TimerSlot>(2048);

    /** Creates a new instance of TimerTask */

    public TimerTask() {

    }

    /**设置定时器，并放入队列*/

    public synchronized Object setTimer(String taskname, String eventname, int timerevent, int delay, Object param){

        TimerSlot slot = new TimerSlot();

        slot.taskname = taskname;

        slot.eventname = eventname;

        slot.timerevent = timerevent;

        slot.expiretime = System.currentTimeMillis() + delay;

        slot.param = param;

        try {

            queue_.put(slot);

        } catch (Exception ex) {

        }

        return 0;

    }

    /**去掉指定的定时器*/

    protected synchronized int killTimer(Object timer){

        if (queue_.remove(timer)){

            return 0;

        }

        return -1;

    }

    /**关闭操作*/

    public void close(){

        queue_.clear();

    }

    /**线程运行，检查定时器是否触发*/

    public void run(){

        while (true){

            try{

                TimerSlot slot = queue_.peek();

                    if (slot == null) {

                        Thread.sleep(50);

                        continue;

                    }

                    long now = System.currentTimeMillis();

                    if (now < slot.expiretime) {

                        Thread.sleep(Math.min(slot.expiretime-now,50));

                        continue;

                    }

                    queue_.remove();

                    TaskMsg taskmsg = new TaskMsg();

                    taskmsg.eventName=slot.eventname;

                    taskmsg.eventNo = slot.timerevent;

                    taskmsg.msg = (slot.param);

                    taskmsg.sender = "__timer";

                    taskmsg.receiver = slot.taskname;

                    TaskFactory.getInstance().getTaskByName(slot.taskname).

                            putmsgtoqueue(taskmsg);

            }catch(InterruptedException e){

                return;

            }

        }

    }

    class TimerSlot implements java.lang.Comparable<TimerSlot>{

        public String eventname;

        public String taskname;

        public int timerevent;

        public long expiretime; // ms, System.current+delay

        public Object param;

        public int compareTo(TimerSlot  other) {

            return (int)(this.expiretime-other.expiretime);

        }

    }

}