SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd");
Date date;
try {
date = new Date();
Calendar calender = Calendar.getInstance();
calender.setTime(date);
calender.add(Calendar.MONTH, 1);
String dd = simpleDateFormat.format(calender.getTime());
实体类别名.set属性名称(simpleDateFormat.parse(dd));
} catch (ParseException e) {
e.printStackTrace();
}