JAVA計時器－楊 bey kuen的部落格

Timer與TimerTask應用。利用 timer.schedule(new RemindTask() , now, minutes * 2 * 1000)，來實現從程式啟動後每隔幾秒鐘執行一次應用程式，並限定執行幾次後程式自動停止，範例如下：

package testjava;

import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;

public class EggTimer {

    private final Timer timer = new Timer();
    private final int minutes;
    public EggTimer(int minutes) {
        this.minutes = minutes;
    }

    public void start() {
        Date now = new Date();
        timer.schedule(new RemindTask() , now, minutes * 2 * 1000);

}

class RemindTask extends TimerTask {
int runtimer= 10;

        public void run(){
            if (runtimer> 0){
                System.out.println(runtimer+":Beep! "+ new java.util.Date());
                runtimer--;
            } else{
                System.out.println(runtimer+" Time''s up!! "+ new java.util.Date());
                timer.cancel(); //call System.exit is the same to stop PGM
                //System.exit(0);   //Stops the AWT thread (and everything else)
            }
        }
    }

    public static void main(String[] args) throws Exception {
        System.out.println("開始時間:" + new java.util.Date());
        EggTimer eggTimer = new EggTimer(1);
        eggTimer.start();
    }
}

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範例二 : 每週日午夜零時執行一次
/* class MainApplication */
package sche.*;
import java.util.Calendar;
import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;

public class MainApplication {
public static void main(String[] args) {
Timer timer = new Timer();
Calendar date = Calendar.getInstance();
date.set(Calendar.DAY_OF_WEEK, Calendar.SUNDAY);
date.set(Calendar.HOUR, 0);
date.set(Calendar.MINUTE, 0);
date.set(Calendar.SECOND, 0);
date.set(Calendar.MILLISECOND, 0);
// 每週日午夜零時執行一次
timer.schedule(new ReportGenerator(),date.getTime(),1000 * 60 * 60 * 24 * 7);
}