按格式取系统日期

// 按格式取系统日期
public static String getDateWithYMD() {
   Calendar now = Calendar.getInstance();
   int month = now.get(Calendar.MONTH) + 1;
   int day = now.get(Calendar.DAY_OF_MONTH);
   int year = now.get(Calendar.YEAR);
   String date = year + "-" + month + "-" + day;
   return date;
}