Java 定时删除文件

import java.io.File;import java.util.Calendar;import java.util.Date;import java.util.Timer;import java.util.TimerTask;public class FileDeleter extends TimerTask {    private static final String targetPath1 = "C:\\Program Files\\Tencent\\QQ\\.......\\image";    private static final String targetPath2 = "C:\\Program Files\\Tencent\\QQ\\...........\\QQPhoto";    private Timer timer = new Timer();        private Calendar calendar = Calendar.getInstance();    public static void main(String[] args) {        FileDeleter fm = new FileDeleter();        fm.start();    }    private static void delFiles(String[] dir) {        for (int i = 0; i < dir.length; i++) {            File f = new File(dir[i]);            File[] files = null;            if (f.exists()) {                files = f.listFiles();                for (int j = 0; j < files.length; j++) {                    files[j].delete();                }            }        }    }    public void start() {        //每隔5分钟删除一次        timer.scheduleAtFixedRate(this, new Date(), 1000 * 300);            }    public void run() {                delFiles(new String[] { targetPath1, targetPath2 });            //下班之前停止任务 ~.~        if(calendar.get(Calendar.HOUR_OF_DAY) == 17 && calendar.get(Calendar.MINUTE) == 15){            this.cancel();        }    }}