public boolean isTime(String wfsj) throws ParseException {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date today = sdf.parse(wfsj);
        SimpleDateFormat df = new SimpleDateFormat("HH:mm:ss");//設定日期格式

        Date nowTime =df.parse(df.format(today));
        
 
//上午的規定時間
        Date amBeginTime = df.parse("00:00:00");
        Date amEndTime = df.parse("07:00:00");
        //下午的規定時間
        Date pmBeginTime = df.parse("21:00:00");
        Date pmEndTime = df.parse("23:59:59");

        //呼叫判斷方法是否在規定時間段內
        boolean isTime = timeCalendar(nowTime, amBeginTime, amEndTime,pmBeginTime,pmEndTime);

        
 
if(isTime){
            //處於規定的時間段內
            System.out.println(isTime);
        }else{
            //不處於規定的時間段內
            System.out.println(isTime);
        }
        return isTime;
    }

public static boolean timeCalendar(Date nowTime, Date amBeginTime, Date amEndTime, Date pmBeginTime, Date pmEndTime) {
    //設定當前時間
    Calendar date = Calendar.getInstance();
    date.setTime(nowTime);
    //設定開始時間
    Calendar amBegin = Calendar.getInstance();
    amBegin.setTime(amBeginTime);//上午開始時間
    Calendar pmBegin = Calendar.getInstance();
    pmBegin.setTime(pmBeginTime);//下午開始時間
    //設定結束時間
    Calendar amEnd = Calendar.getInstance();
    amEnd.setTime(amEndTime);//上午結束時間
    Calendar pmEnd = Calendar.getInstance();
    pmEnd.setTime(pmEndTime);//下午結束時間
    //處於開始時間之後，和結束時間之前的判斷
    if ((date.after(amBegin) && date.before(amEnd)) || (date.after(pmBegin) && date.before(pmEnd))) {
        return true;
    } else {
        return false;
    }
}