獲取指點日期的月度等數值 時間set add的區別

獲取指點日期的月份等數值 時間set add的區別

?

private int getTheMonthsValue(Date date) {Calendar calendar = Calendar.getInstance();calendar.setTime(date);return calendar.get(Calendar.MONTH) + 1;}

private int getTheMonthsValue2(Date date) {GregorianCalendar g = new GregorianCalendar();g.setTime(date);int flag = (int) g.get(Calendar.MONTH) + 1;return flag;}

真悲劇 居然沒留意到 Calendar這個類有add() 和 set()區別;

private Date getTime(Date date) {Calendar calendar = Calendar.getInstance();calendar.setTime(date);calendar.set(Calendar.DATE, 1);return calendar.getTime();}private Date getTime2(Date date) {Calendar lastDate = Calendar.getInstance();lastDate.setTime(date);lastDate.add(Calendar.DAY_OF_MONTH, 1);return lastDate.getTime();}

System.out.println(dateFormat.format(test.getTime(date)));System.out.println(dateFormat.format(test.getTime2(date)));

結果:

2011-07-012011-07-16