java中处理日期 日期向前推 日期向后 推

1. /**
2. *向前后推算时间正负都可以
3. *@paramdays
4. *@return
5. */
6. publicstaticStringtimeUtil(intdays){
7. SimpleDateFormatsd=newSimpleDateFormat("yyyy-MM-dd");
8. Calendarcalendar=Calendar.getInstance();
9. inti=calendar.get(Calendar.DAY_OF_YEAR);
10. i=i+days;
11. calendar.set(Calendar.DAY_OF_YEAR,i);
12. returnsd.format(calendar.getTime());
13. }