java 获得指定日期的前一天代码收藏

/** * 获得指定日期的前一天 *  * @param specifiedDay flag flag 判断是前一天还是后一天 * @return * @throws Exception */public static String getSpecifiedDayBefore(String specifiedDay, String flag) {Calendar c = Calendar.getInstance();Date date = null;try {date = new SimpleDateFormat("yy-MM-dd").parse(specifiedDay);} catch (ParseException e) {e.printStackTrace();}c.setTime(date);int day = c.get(Calendar.DATE);if ("前一天".equals(flag)) {c.set(Calendar.DATE, day - 1);} else if ("后一天".equals(flag)) {c.set(Calendar.DATE, day + 1);}String dayBefore = new SimpleDateFormat("yyyy-MM-dd").format(c.getTime());return dayBefore;}