問(wèn)題描述
我在數(shù)據(jù)庫(kù)中有 2 個(gè)代表公司工作時(shí)間的日期對(duì)象.
I have 2 date object in the database that represent the company's working hours.
我只需要時(shí)間，但因?yàn)槲冶仨毐４嫒掌?它看起來(lái)像這樣:
I only need the hours but since I have to save date. it appears like this:
Date companyWorkStartHour;
Date companyWorkEndHour;
開(kāi)始時(shí)間:12-12-2001-13:00:00結(jié)束時(shí)間:12-12-2001-18:00:00
start hours: 12-12-2001-13:00:00 finish hours: 12-12-2001-18:00:00
我有公司和用戶(hù)的時(shí)區(qū).(我的服務(wù)器可能在另一個(gè)時(shí)區(qū)).
I have the timezone of the company and of the user. (my server may be in another timezone).
TimeZone userTimeZone;
TimeZone companyTimeZone;
我需要檢查用戶(hù)的當(dāng)前時(shí)間(考慮到他的時(shí)區(qū))是否在公司工作時(shí)間內(nèi)(考慮到公司的時(shí)區(qū)).
I need to check if the user's current time (considering his timezone) is within the company working hours (considering the company's time zone).
我該怎么做?我在 Java 日歷上苦苦掙扎了一個(gè)多星期，但沒(méi)有成功！
How can I do it? I am struggling for over a week with Java calendar and with no success!
推薦答案
java.util.Date 類(lèi)是一個(gè)容器，它保存了自 1970 年 1 月 1 日 00:00:00 以來(lái)的毫秒數(shù)世界標(biāo)準(zhǔn)時(shí)間.請(qǐng)注意，類(lèi) Date 對(duì)時(shí)區(qū)一無(wú)所知.如果您需要使用時(shí)區(qū)，請(qǐng)使用類(lèi) Calendar.(edit 2017 年 1 月 19 日:如果您使用的是 Java 8，請(qǐng)使用包 java.time 中的新日期和時(shí)間 API).
The java.util.Date class is a container that holds a number of milliseconds since 1 January 1970, 00:00:00 UTC. Note that class Date doesn't know anyting about timezones. Use class Calendar if you need to work with timezones. (edit 19-Jan-2017: if you are using Java 8, use the new date and time API in package java.time).
Class Date 并不適合保存沒(méi)有日期的小時(shí)數(shù)(例如 13:00 或 18:00).它根本不是為了那個(gè)目的而設(shè)計(jì)的，所以如果你嘗試像那樣使用它，就像你正在做的那樣，你會(huì)遇到很多問(wèn)題，你的解決方案也不會(huì)優(yōu)雅.
Class Date is not really suited for holding an hour number (for example 13:00 or 18:00) without a date. It's simply not made for that purpose, so if you try to use it like that, as you seem to be doing, you'll run into a number of problems and your solution won't be elegant.
如果您忘記使用類(lèi) Date 來(lái)存儲(chǔ)工作時(shí)間而只使用整數(shù)，這會(huì)簡(jiǎn)單得多:
If you forget about using class Date to store the working hours and just use integers, this will be much simpler:
Date userDate = ...;
TimeZone userTimeZone = ...;
int companyWorkStartHour = 13;
int companyWorkEndHour = 18;
Calendar cal = Calendar.getInstance();
cal.setTime(userDate);
cal.setTimeZone(userTimeZone);
int hour = cal.get(Calendar.HOUR_OF_DAY);
boolean withinCompanyHours = (hour >= companyWorkStartHour && hour < companyWorkEndHour);
如果您還想考慮幾分鐘(而不僅僅是幾小時(shí))，您可以這樣做:
If you also want to take minutes (not just hours) into account, you could do something like this:
int companyWorkStart = 1300;
int companyWorkEnd = 1830;
int time = cal.get(Calendar.HOUR_OF_DAY) * 100 + cal.get(Calendar.MINUTE);
boolean withinCompanyHours = (time >= companyWorkStart && time < companyWorkEnd);
這篇關(guān)于為如何比較 Java 中不同時(shí)區(qū)的時(shí)間而苦惱?的文章就介紹到這了，希望我們推薦的答案對(duì)大家有所幫助，也希望大家多多支持html5模板網(wǎng)！