我怎样才能得到31天前的日期？

Question

我怎么能x在31天之前得到哪一个current_date？

x(date)___________________________current_date
                       31 

Answer 1

只需减去31天.例如:

LocalDate current = new LocalDate(2015, 6, 19);
LocalDate x = current.minusDays(31); // 2015-05-19

要获取当前日期,您可以使用:

LocalDate current = new LocalDate(); // Default time zone

要么

LocalDate current = new LocalDate(zone); // Some specific zone

或者你可能想要创建自己的"时钟"表示,它能够给你当前的Instant,在这种情况下你可以使用:

LocalDate current = clock.getCurrentInstant().toDateTime(zone).toLocalDate();

(这允许您使用依赖注入来使用假时钟编写更简单的单元测试.)

Answer 2

你可以试试这个：

LocalDate current = new LocalDate();//Constructs an instance set to the current local time evaluated using ISO chronology in the default zone.
LocalDate x = current.minusDays(31);

否则你可以尝试：

LocalDate current = LocalDate.now();//Obtains a LocalDate set to the current system millisecond time using ISOChronology in the default time zone
LocalDate x = current.minusDays(31);