Android 獲取幾天後的時間

 String temp = CommomDataManager.getRepaymentPeriod();
                ArrayList list = new ArrayList();
                DateFormat format = new SimpleDateFormat("yyyy-MM-dd");
                Calendar calendar = Calendar.getInstance();
                for (int i = 0;i < temp.split(",").length;i++) {
                    String day = temp.split(",")[i];
                    calendar.add(Calendar.DATE,Integer.parseInt(day));
                    list.add(String.format("第{0}期還款日期:{1}",i + 1,format.format(calendar.getTime())));
//                    list.add("第{0}期還款日期:{1}",)
                }