java实现 取当前时间的前7天的日期

public String getStatetime() throws ParseException{
  
  SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
       
        Calendar c = Calendar.getInstance();  
        c.add(Calendar.DATE, - 7);  
        Date monday = c.getTime();
        String preMonday = sdf.format(monday);
        return preMonday;
   }