Java比较两个日期的大小

public static String getComparedSBQDate(String yxqq,String starttime){

        String str = starttime;

        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd", Locale.CHINA);

        try {

            Date d1 = sdf.parse(yxqq);

            Date d2 = sdf.parse(starttime);

            if(d1.before(d2)){

                 str = starttime;

            }else{

                 str = yxqq;

            }

        } catch (ParseException e) {

            e.printStackTrace();

        }

        return str;

    }