得到格式化时间

        Calendar cal = Calendar.getInstance();
        //每次向前推一天
        cal.add(Calendar.DATE, -60);
        //cal.set(Calendar.DAY_OF_MONTH, 0);
        cal.set(Calendar.HOUR_OF_DAY, 0);
        cal.set(Calendar.SECOND,0);
        cal.set(Calendar.MINUTE,0);

        System.out.println(cal.getTime());

        Sun Sep 07 00:00:00 CST 2014