怎么将字符串的date转换为alarm

AlarmManager am = (AlarmManager)context.getSystemService(Context.ALARM_SERVICE); 
  SimpleDateFormat  dt = new SimpleDateFormat("hh:mm"); 
  Date date = new Date();  //当前时间日期
     try {
                 Date dateTime = dt.parse(str);
         date.setHours(dateTime.getHours())；
             date.setMinutes(dateTime.getMinutes());

     } catch (ParseException e) {
            e.printStackTrace();
    }         
 am.set(AlarmManager.RTC_WAKEUP,date.getTime(), contentIntent);