如何使Date与地区无关? [英] How to make Date locale-independent?

问题描述

我有一个数据库，它以GMT时区以OleDateTime格式存储日期.我实现了一个类，在Java中扩展了Date，以经典的日期格式表示该类.但是我的课程是与语言环境相关的(我在GMT + 2中).因此，它将db中的日期转换为date - 2 hours.如何使其正确转换日期?我希望我的班级始终与区域设置无关，始终使用GMT时区.实际上，问题是:

I have a db, that stores dates in OleDateTime format, in GMT timezone. I've implemented a class, extending Date in java to represent that in classic date format. But my class is locale-dependent (I'm in GMT+2). Therefore, it converts the date in the db as date - 2 hours. How do I make it convert the date correctly? I want my class to be locale-independent, always using GMT timezone. Actually, the question is:

class MyOleDateTime extends Date {

    static {
        Locale.setDefault(WhatGoesHere?)
    }

    // ... some constructors
    // ... some methods
}

推荐答案

好吧，最好像其他答案中所建议的那样使用Calendar对象.但是，如果您真的要设置全局时区，则可以在应用程序代码的早期使用TimeZone.setDefault(TimeZone.getTimeZone("UTC"));.还有user.timezone Java系统属性.

Well, it's better to use the Calendar object like suggested in other answers. However, if you really want to set global timezone, you can use TimeZone.setDefault(TimeZone.getTimeZone("UTC")); early in your application code. There is also user.timezone Java system property.

另外(只是很有趣)，看来按格林尼治标准时间/世界标准时间(不夏令时更改)实际居住的唯一国家是利比里亚.

Also (just fun to know), it appears that the only country actually living by GMT/UTC time (without daylight saving changes) is Liberia.

实际上，Date个对象本身总是 与语言环境和时区无关.它的getTime()方法将始终返回UTC 中自1970年1月1日00:00:00以来经过的毫秒数(不计算leap秒).但是，如果您想获得毫秒以外的其他信息，则必须使用Calendar，它与时区相关.但这是正确的方法.您不会在Date类中使用不赞成使用的方法，对吗?

In fact, Date objects per se are always locale- and timezone-independent. Its getTime() method will always return the number of milliseconds passed since January 1, 1970 00:00:00 (not counting leap seconds) in UTC. But if you want to get something else than milliseconds, you have to use Calendar, which is timezone-dependent. But it is the right way to go. You don't use that deprecated methods in Date class, do you?

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