如何截取成只含年月日的日期？不懂的新手看看哦

时间字段原来是这样：2016-08-09T09:32:59
想截取成：2016-08-09
回答：

Calendar calendar=Calendar.getInstance();int year=calendar.get(Calendar.YEAR);int month=calendar.get(Calendar.MONTH)+1;int day=calendar.get(Calendar.DAY_OF_MONTH);int hours = calendar.get(Calendar.HOUR_OF_DAY);int minutes = calendar.get(Calendar.MINUTE);int seconds = 0;String dateTimeStr = String.format("%04d-%02d-%02d-%02d:%02d:%02d", year, month, day, hours, minutes, seconds);

dateTimeStr = String.format("%04d-%02d-%02d", year, month, day);

String oldDate ="2016-08-09T09:32:59";String newDate= oldDate.subString(0, oldDate.indexof('T'));或者  newDate=oldDate.split("T")[0];

外层最好加上try catch 顺便开始时候判断一下 字符串是否为空