java之時間戳處理

●時間戳(timestamp)定義

時間戳指的是從格林威治時間1970年01月01日00時00分00秒起至現在的總秒數。嚴格來說，不管你處在地球上的哪個地方，任意時間點的時間戳都是相同的。這點有利於線上和客戶端分布式應用統一追蹤時間信息。時間戳是沒有時區概念的，同一個時間戳對不同時區顯示的時間不一樣而已。

　　

　　最近在做一個api的自測時發現，在不同環境同一個api返回的response里的時間戳結果不太一樣。查看了下編程邏輯，代碼如下：

                    SimpleDateFormat sDateFormat = new SimpleDateFormat("yyyy-MM-dd");
                    Date date = sDateFormat.parse(m.getDaytime());//格式類似"2020-02-20"
                    getEventNumDateResponse.setTime(date.getTime());
                    sDateFormat = null;

　　這段代碼邏輯上沒什么問題，但在不同環境上運行結果不一樣，問題出在哪了？

　　細想，懷疑Date與時區肯定有關系，經過檢查，發現本地的時區是默認的東八區UTC+0800，本地java 程序運行也沒配置時區，采用的自然是系統時區東八區，而在另外一個開發環境，jar包運行時配置了-Duser.timezone=UTC，雖然系統默認也是東八區，原來是這個設置導致的。

　　比如"2020-02-20"這個字符串時間，被SimpleDateFormat parse后，如果當前的運行時區（沒設置則是系統時區）是UTC+0800，則時間Date是：Thu Feb 20 00:00:00 CST 2020

　　CST時區包含了UTC+8:00 也就是這個時間自然是東八區的 2020-02-20 00:00:00 這個時間，對應着是UTC 0時區的2020-02-19 16:00:00時間，通過getTime獲取的時間戳是：

System.out.println(TimeZone.getDefault().getRawOffset());
28800000

System.out.println(sdf.parse("2020-02-20").getTime());
1582128000000

通過在pg里轉化驗證：
SELECT TO_TIMESTAMP(1582128000)AT TIME ZONE 'UTC-0' ;
2020-02-19 16:00:00

SELECT TO_TIMESTAMP(1582128000)AT TIME ZONE 'Asia/Shanghai' ;
2020-02-20 00:00:00

    同樣，當我們在系統里設置了時區為UTC 0時區，或者在jar運行時設置了-Duser.timezone=UTC，或者在代碼里配置了

    

TimeZone.setDefault(TimeZone.getTimeZone("UTC"));

　　這樣，當后面SimpleDateFormat parse后， 則時間Date是：Thu Feb 20 00:00:00 UTC 2020，表明是UTC 0時區的 2020-02-20 00:00:00 這個時間，對應着是UTC+8時區的

2020-02-20 08:00:00時間，通過getTime獲取的時間戳是：

System.out.println(TimeZone.getDefault().getRawOffset());
0

System.out.println(sdf.parse("2020-02-20").getTime());
1582156800000

通過在pg里轉化驗證：
SELECT TO_TIMESTAMP(1582156800)AT TIME ZONE 'UTC-0' ;
2020-02-20 00:00:00

----直接寫時區偏移(基於格林威治時區，是反的，即提前-滯后+，例如正常東八區，需要寫-8:00，因此建議直接用時區縮寫，見后面附表，當然也可以寫

---Asia/Shanghai表示東八區

SELECT TO_TIMESTAMP(1582156800)AT TIME ZONE 'Asia/Shanghai' ; 
2020-02-20 08:00:00

     寫到這里，相信大家都明白了為啥同一個程序在不同機器上跑出的涉及時間戳的結果不一致，這一點要注意額，千萬別掉坑里。

     最后，說一下涉及時間戳時，配置時區的幾種方式：

Linux中：（以redhat 7.0為例）

查看：
[root@localhost Desktop]# timedatectl status
      Local time: Thu 2020-02-27 14:57:58 CST
  Universal time: Thu 2020-02-27 06:57:58 UTC
        RTC time: Thu 2020-02-27 06:58:00
       Time zone: Asia/Shanghai (CST, +0800)
     NTP enabled: yes
NTP synchronized: no
 RTC in local TZ: no
      DST active: n/a

或者：

[root@localhost Desktop]# date -R
Thu, 27 Feb 2020 15:00:25 +0800

設置：
# timedatectl set-timezone "Asia/Shanghai"

 

在Java中也可以設置時區

1）啟動設置
java -Duser.timezone=Asia/Shanghai -jar xxx.jar

 

2) 代碼中設置

TimeZone.setDefault(TimeZone.getTimeZone("UTC"));
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
System.out.println(sdf.parse("2018-09-01 08:00:00").getTime());

3) 單次處理生效，建議使用joda的時間包

<dependency>
    <groupId>joda-time</groupId>
    <artifactId>joda-time</artifactId>
    <version>2.9.9</version>
</dependency>

DateTimeFormatter dateTimeFormatter = DateTimeFormat.forPattern("yyyy-MM-dd HH:mm:ss").withChronology(ISOChronology.getInstance(DateTimeZone.forID("Asia/Shanghai")));
System.out.println(dateTimeFormatter.parseDateTime("2018-09-01 08:00:00").getMillis());

      另外，了解Java8 的朋友可能都知道，Java8提供了一套新的時間處理API，這套API比以前的時間處理API要友好的多。

 

　　Java8 中加入了對時區的支持，帶時區的時間為分別為：ZonedDate、ZonedTime、ZonedDateTime。其中每個時區都對應着 ID，地區ID都為 “{區域}/{城市}”的格式，如Asia/Shanghai、America/Los_Angeles等。

      Java中的Date類中是不包含時區信息的，在使用System.out.println打印Date的時候，回調用Date.toString方法，該方法會獲取系統的默認時區來轉換時間。

       在Java8中可以使用ZonedTime、ZonedDate和ZonedDateTime來表示帶有時區信息的時間。

LocalDateTime now = LocalDateTime.now(ZoneId.of("America/Los_Angeles")); 
System.out.println(now);

//獲取秒數
Long second = LocalDateTime.now().toEpochSecond(ZoneOffset.of("+8"));
//獲取毫秒數
Long milliSecond = LocalDateTime.now().toInstant(ZoneOffset.of("+8")).toEpochMilli();

//時間轉字符串格式化
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMMddHHmmssSSS");
String dateTime = LocalDateTime.now(ZoneOffset.of("+8")).format(formatter);

//字符串轉時間
String dateTimeStr = "2018-07-28 14:11:15";
DateTimeFormatter df = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");

LocalDateTime localDateTime = LocalDateTime.now(); Date date = Date.from(localDateTime.atZone(ZoneOffset.ofHours(8)).toInstant());

 

 

 

 

附幾種時區標准：

1.UTC

UTC＋時區差＝本地時間

時區差東為正，西為負

UTC是協調世界時(Universal Time Coordinated)英文縮寫，是由國際無線電咨詢委員會規定和推薦,並由國際時間局(BIH)負責保持的以秒為基礎的時間標度。UTC相當於本初子午線(即經度0度)上的平均太陽時，過去曾用格林威治平均時(GMT)來表示.北京時間比UTC時間早8小時，以1999年1月1日0000UTC為例，UTC時間是零點，北京時間為1999年1月1日早上8點整。

 

2.GMT(Greenwich Mean Time)是格林尼治平時： 
由於地球軌道並非圓形，其運行速度又隨着地球與太陽的距離改變而出現變化，因此視太陽時欠缺均勻性。視太陽日的長度同時亦受到地球自轉軸相對軌道面的傾斜度所影響。為着要糾正上述的不均勻性，天文學家計算地球非圓形軌跡與極軸傾斜對視太陽時的效應。平太陽時就是指經修訂后的視太陽時。在格林尼治子午線上的平太陽時稱為世界時(UT0)，又叫格林尼治平時(GMT)。 為了確保協調世界時與世界時(UT1)相差不會超過0.9秒，有需要時便會在協調世界時內加上正或負閏秒。因此協調世界時與國際原子時(TAI)之間會出現若干整數秒的差別。位於巴黎的國際地球自轉事務中央局(IERS)負責決定何時加入閏秒。

也就是說，UTC 基本上等於GMT

 

3.CET

（英語：Central European Time，CET）歐洲中部時間是比世界標准時間（UTC）早一個小時的時區名稱之一。它被大部分歐洲國家和部分北非國家采用。冬季時間為UTC+1，夏季歐洲夏令時為UTC+2。

 

4.CEST

歐洲中部夏令時間（Central European Summer Time，簡稱CEST）比世界標准時間（UTC）早兩個小時的時區名稱之一。它被大部分歐洲國家和部分北非國家在夏天采用(UTC+2)，冬季這些國家使用歐洲中部時間（UTC+1）

 

附JAVA TIMEZONE 時區表：

Etc/GMT+12

Etc/GMT+11
MIT
Pacific/Apia
Pacific/Midway
Pacific/Niue
Pacific/Pago_Pago
Pacific/Samoa
US/Samoa
America/Adak
America/Atka

Etc/GMT+10
HST
Pacific/Fakaofo
Pacific/Honolulu
Pacific/Johnston
Pacific/Rarotonga
Pacific/Tahiti
SystemV/HST10
US/Aleutian
US/Hawaii
Pacific/Marquesas
AST
America/Anchorage
America/Juneau
America/Nome
America/Yakutat

Etc/GMT+9
Pacific/Gambier
SystemV/YST9
SystemV/YST9YDT
US/Alaska
America/Dawson
America/Ensenada
America/Los_Angeles
America/Tijuana
America/Vancouver
America/Whitehorse
Canada/Pacific
Canada/Yukon

Etc/GMT+8
Mexico/BajaNorte
PST
PST8PDT
Pacific/Pitcairn
SystemV/PST8
SystemV/PST8PDT
US/Pacific
US/Pacific-New
America/Boise
America/Cambridge_Bay
America/Chihuahua
America/Dawson_Creek
America/Denver
America/Edmonton
America/Hermosillo
America/Inuvik
America/Mazatlan
America/Phoenix
America/Shiprock
America/Yellowknife
Canada/Mountain

Etc/GMT+7
MST
MST7MDT
Mexico/BajaSur
Navajo
PNT
SystemV/MST7
SystemV/MST7MDT
US/Arizona
US/Mountain
America/Belize
America/Cancun
America/Chicago
America/Costa_Rica
America/El_Salvador
America/Guatemala
America/Indiana/Knox
America/Indiana/Tell_City
America/Knox_IN
America/Managua
America/Menominee
America/Merida
America/Mexico_City
America/Monterrey
America/North_Dakota/Center
America/North_Dakota/New_Salem
America/Rainy_River
America/Rankin_Inlet
America/Regina
America/Swift_Current
America/Tegucigalpa
America/Winnipeg
CST
CST6CDT
Canada/Central
Canada/East-Saskatchewan
Canada/Saskatchewan
Chile/EasterIsland

Etc/GMT+6
Mexico/General
Pacific/Easter
Pacific/Galapagos
SystemV/CST6
SystemV/CST6CDT
US/Central
US/Indiana-Starke
America/Atikokan
America/Bogota
America/Cayman
America/Coral_Harbour
America/Detroit
America/Eirunepe
America/Fort_Wayne
America/Grand_Turk
America/Guayaquil
America/Havana
America/Indiana/Indianapolis
America/Indiana/Marengo
America/Indiana/Petersburg
America/Indiana/Vevay
America/Indiana/Vincennes
America/Indiana/Winamac
America/Indianapolis
America/Iqaluit
America/Jamaica
America/Kentucky/Louisville
America/Kentucky/Monticello
America/Lima
America/Louisville
America/Montreal
America/Nassau
America/New_York
America/Nipigon
America/Panama
America/Pangnirtung
America/Port-au-Prince
America/Porto_Acre
America/Resolute
America/Rio_Branco
America/Thunder_Bay
America/Toronto
Brazil/Acre
Canada/Eastern
Cuba
EST
EST5EDT

Etc/GMT+5
IET
Jamaica
SystemV/EST5
SystemV/EST5EDT
US/East-Indiana
US/Eastern
US/Michigan
America/Caracas
America/Anguilla
America/Antigua
America/Aruba
America/Asuncion
America/Barbados
America/Blanc-Sablon
America/Boa_Vista
America/Campo_Grande
America/Cuiaba
America/Curacao
America/Dominica
America/Glace_Bay
America/Goose_Bay
America/Grenada
America/Guadeloupe
America/Guyana
America/Halifax
America/La_Paz
America/Manaus
America/Marigot
America/Martinique
America/Moncton
America/Montserrat
America/Port_of_Spain
America/Porto_Velho
America/Puerto_Rico
America/Santiago
America/Santo_Domingo
America/St_Barthelemy
America/St_Kitts
America/St_Lucia
America/St_Thomas
America/St_Vincent
America/Thule
America/Tortola
America/Virgin
Antarctica/Palmer
Atlantic/Bermuda
Atlantic/Stanley
Brazil/West
Canada/Atlantic
Chile/Continental

Etc/GMT+4
PRT
SystemV/AST4
SystemV/AST4ADT
America/St_Johns
CNT
Canada/Newfoundland
AGT
America/Araguaina
America/Argentina/Buenos_Aires
America/Argentina/Catamarca
America/Argentina/ComodRivadavia
America/Argentina/Cordoba
America/Argentina/Jujuy
America/Argentina/La_Rioja
America/Argentina/Mendoza
America/Argentina/Rio_Gallegos
America/Argentina/San_Juan
America/Argentina/San_Luis
America/Argentina/Tucuman
America/Argentina/Ushuaia
America/Bahia
America/Belem
America/Buenos_Aires
America/Catamarca
America/Cayenne
America/Cordoba
America/Fortaleza
America/Godthab
America/Jujuy
America/Maceio
America/Mendoza
America/Miquelon
America/Montevideo
America/Paramaribo
America/Recife
America/Rosario
America/Sao_Paulo
Antarctica/Rothera
BET
Brazil/East

Etc/GMT+3
America/Noronha
Atlantic/South_Georgia
Brazil/DeNoronha

Etc/GMT+2
America/Scoresbysund
Atlantic/Azores
Atlantic/Cape_Verde

Etc/GMT+1
Africa/Abidjan
Africa/Accra
Africa/Bamako
Africa/Banjul
Africa/Bissau
Africa/Casablanca
Africa/Conakry
Africa/Dakar
Africa/El_Aaiun
Africa/Freetown
Africa/Lome
Africa/Monrovia
Africa/Nouakchott
Africa/Ouagadougou
Africa/Sao_Tome
Africa/Timbuktu
America/Danmarkshavn
Atlantic/Canary
Atlantic/Faeroe
Atlantic/Faroe
Atlantic/Madeira
Atlantic/Reykjavik
Atlantic/St_Helena
Eire

Etc/GMT

Etc/GMT+0

Etc/GMT-0

Etc/GMT0
Etc/Greenwich
Etc/UCT
Etc/UTC
Etc/Universal
Etc/Zulu
Europe/Belfast
Europe/Dublin
Europe/Guernsey
Europe/Isle_of_Man
Europe/Jersey
Europe/Lisbon
Europe/London
GB
GB-Eire
GMT
GMT0
Greenwich
Iceland
Portugal
UCT
UTC
Universal
WET
Zulu
Africa/Algiers
Africa/Bangui
Africa/Brazzaville
Africa/Ceuta
Africa/Douala
Africa/Kinshasa
Africa/Lagos
Africa/Libreville
Africa/Luanda
Africa/Malabo
Africa/Ndjamena
Africa/Niamey
Africa/Porto-Novo
Africa/Tunis
Africa/Windhoek
Arctic/Longyearbyen
Atlantic/Jan_Mayen
CET
ECT

Etc/GMT-1
Europe/Amsterdam
Europe/Andorra
Europe/Belgrade
Europe/Berlin
Europe/Bratislava
Europe/Brussels
Europe/Budapest
Europe/Copenhagen
Europe/Gibraltar
Europe/Ljubljana
Europe/Luxembourg
Europe/Madrid
Europe/Malta
Europe/Monaco
Europe/Oslo
Europe/Paris
Europe/Podgorica
Europe/Prague
Europe/Rome
Europe/San_Marino
Europe/Sarajevo
Europe/Skopje
Europe/Stockholm
Europe/Tirane
Europe/Vaduz
Europe/Vatican
Europe/Vienna
Europe/Warsaw
Europe/Zagreb
Europe/Zurich
MET
Poland
ART
Africa/Blantyre
Africa/Bujumbura
Africa/Cairo
Africa/Gaborone
Africa/Harare
Africa/Johannesburg
Africa/Kigali
Africa/Lubumbashi
Africa/Lusaka
Africa/Maputo
Africa/Maseru
Africa/Mbabane
Africa/Tripoli
Asia/Amman
Asia/Beirut
Asia/Damascus
Asia/Gaza
Asia/Istanbul
Asia/Jerusalem
Asia/Nicosia
Asia/Tel_Aviv
CAT
EET
Egypt

Etc/GMT-2
Europe/Athens
Europe/Bucharest
Europe/Chisinau
Europe/Helsinki
Europe/Istanbul
Europe/Kaliningrad
Europe/Kiev
Europe/Mariehamn
Europe/Minsk
Europe/Nicosia
Europe/Riga
Europe/Simferopol
Europe/Sofia
Europe/Tallinn
Europe/Tiraspol
Europe/Uzhgorod
Europe/Vilnius
Europe/Zaporozhye
Israel
Libya
Turkey
Africa/Addis_Ababa
Africa/Asmara
Africa/Asmera
Africa/Dar_es_Salaam
Africa/Djibouti
Africa/Kampala
Africa/Khartoum
Africa/Mogadishu
Africa/Nairobi
Antarctica/Syowa
Asia/Aden
Asia/Baghdad
Asia/Bahrain
Asia/Kuwait
Asia/Qatar
Asia/Riyadh
EAT

Etc/GMT-3
Europe/Moscow
Europe/Volgograd
Indian/Antananarivo
Indian/Comoro
Indian/Mayotte
W-SU
Asia/Riyadh87
Asia/Riyadh88
Asia/Riyadh89
Mideast/Riyadh87
Mideast/Riyadh88
Mideast/Riyadh89
Asia/Tehran
Iran
Asia/Baku
Asia/Dubai
Asia/Muscat
Asia/Tbilisi
Asia/Yerevan

Etc/GMT-4
Europe/Samara
Indian/Mahe
Indian/Mauritius
Indian/Reunion
NET
Asia/Kabul
Asia/Aqtau
Asia/Aqtobe
Asia/Ashgabat
Asia/Ashkhabad
Asia/Dushanbe
Asia/Karachi
Asia/Oral
Asia/Samarkand
Asia/Tashkent
Asia/Yekaterinburg

Etc/GMT-5
Indian/Kerguelen
Indian/Maldives
PLT
Asia/Calcutta
Asia/Colombo
Asia/Kolkata
IST
Asia/Katmandu
Antarctica/Mawson
Antarctica/Vostok
Asia/Almaty
Asia/Bishkek
Asia/Dacca
Asia/Dhaka
Asia/Novosibirsk
Asia/Omsk
Asia/Qyzylorda
Asia/Thimbu
Asia/Thimphu
BST

Etc/GMT-6
Indian/Chagos
Asia/Rangoon
Indian/Cocos
Antarctica/Davis
Asia/Bangkok
Asia/Ho_Chi_Minh
Asia/Hovd
Asia/Jakarta
Asia/Krasnoyarsk
Asia/Phnom_Penh
Asia/Pontianak
Asia/Saigon
Asia/Vientiane

Etc/GMT-7
Indian/Christmas
VST
Antarctica/Casey
Asia/Brunei
Asia/Choibalsan
Asia/Chongqing
Asia/Chungking
Asia/Harbin
Asia/Hong_Kong
Asia/Irkutsk
Asia/Kashgar
Asia/Kuala_Lumpur
Asia/Kuching
Asia/Macao
Asia/Macau
Asia/Makassar
Asia/Manila
Asia/Shanghai
Asia/Singapore
Asia/Taipei
Asia/Ujung_Pandang
Asia/Ulaanbaatar
Asia/Ulan_Bator
Asia/Urumqi
Australia/Perth
Australia/West
CTT

Etc/GMT-8
Hongkong
PRC
Singapore
Australia/Eucla
Asia/Dili
Asia/Jayapura
Asia/Pyongyang
Asia/Seoul
Asia/Tokyo
Asia/Yakutsk

Etc/GMT-9
JST
Japan
Pacific/Palau
ROK
ACT
Australia/Adelaide
Australia/Broken_Hill
Australia/Darwin
Australia/North
Australia/South
Australia/Yancowinna
AET
Antarctica/DumontDUrville
Asia/Sakhalin
Asia/Vladivostok
Australia/ACT
Australia/Brisbane
Australia/Canberra
Australia/Currie
Australia/Hobart
Australia/Lindeman
Australia/Melbourne
Australia/NSW
Australia/Queensland
Australia/Sydney
Australia/Tasmania
Australia/Victoria

Etc/GMT-10
Pacific/Guam
Pacific/Port_Moresby
Pacific/Saipan
Pacific/Truk
Pacific/Yap
Australia/LHI
Australia/Lord_Howe
Asia/Magadan

Etc/GMT-11
Pacific/Efate
Pacific/Guadalcanal
Pacific/Kosrae
Pacific/Noumea
Pacific/Ponape
SST
Pacific/Norfolk
Antarctica/McMurdo
Antarctica/South_Pole
Asia/Anadyr
Asia/Kamchatka

Etc/GMT-12
Kwajalein
NST
NZ
Pacific/Auckland
Pacific/Fiji
Pacific/Funafuti
Pacific/Kwajalein
Pacific/Majuro
Pacific/Nauru
Pacific/Tarawa
Pacific/Wake
Pacific/Wallis
NZ-CHAT
Pacific/Chatham

Etc/GMT-13
Pacific/Enderbury
Pacific/Tongatapu

Etc/GMT-14
Pacific/Kiritimati

附： PostgreSQL Time Zone Names

 

Names	Offset	Description
FJST	-13:00	Fiji Summer Time
FJT	-12:00	Fiji Time
IDLW	-12:00	International Date Line, West
BST	-11:00	Bering Summer Time
NT	-11:00	Nome Time
NUT	-11:00	Niue Time
AHST	-10:00	Alaska-Hawaii Std Time
CAT	-10:00	Central Alaska Time
HST	-10:00	Hawaii Std Time
THAT	-10:00	Tahiti Time
TKT	-10:00	Tokelau Time
MART	-09:30	Marquesas Time
AKST	-09:00	Alaska Standard Time
GAMT	-09:00	Gambier Time
HDT	-09:00	Hawaii/Alaska Daylight Time
YST	-09:00	Yukon Standard Time
AKDT	-08:00	Alaska Daylight Time
PST	-08:00	Pacific Standard Time
YDT	-08:00	Yukon Daylight Time
MST	-07:00	Mountain Standard Time
PDT	-07:00	Pacific Daylight Time
CST	-06:00	Central Standard Time
EAST	-06:00	Easter Island Time
GALT	-06:00	Galapagos Time
MDT	-06:00	Mountain Daylight Time
ZP6	-06:00	UTC +6 hours
ACT	-05:00	Atlantic/Porto Acre Time
CDT	-05:00	Central Daylight Time
COT	-05:00	Columbia Time
EASST	-05:00	Easter Island Summer Time
ECT	-05:00	Ecuador Time
EST	-05:00	Eastern Standard Time
PET	-05:00	Peru Time
ZP5	-05:00	UTC +5 hours
ACST	-04:00	Atlantic/Porto Acre Summer Time
AMT	-04:00	Amazon Time (Porto Velho)
AST	-04:00	Atlantic Std Time (Canada)
BOT	-04:00	Bolivia Time
CLT	-04:00	Chile Time
ECT	-04:00	Eastern Caribbean Time
EDT	-04:00	Eastern Daylight Time
GYT	-04:00	Guyana Time
PYT	-04:00	Paraguay Time
VET	-04:00	Venezuela Time
ZP4	-04:00	UTC +4 hours
NFT	-03:30	Newfoundland Standard Time
NST	-03:30	Newfoundland Standard Time
ADT	-03:00	Atlantic Daylight Time
AMST	-03:00	Amazon Summer Time (Porto Velho)
ART	-03:00	Argentina Time
AWT	-03:00	Brazil Time
BRT	-03:00	Brasilia Time
BST	-03:00	Brazil Standard Time
CLST	-03:00	Chile Summer Time
FKST	-03:00	Falkland Islands Summer Time
GFT	-03:00	French Guiana Time
PYST	-03:00	Paraguay Summer Time
UYT	-03:00	Uruguay Time
WGT	-03:00	West Greenland Time
NDT	-02:30	Newfoundland Daylight Time
BRST	-02:00	Brasilia Summer Time
FKT	-02:00	Falkland Islands Time
FNT	-02:00	Fernando de Noronha Time
PMDT	-02:00	Pierre & Miquelon Daylight Time
UYST	-02:00	Uruguay Summer Time
WGST	-02:00	West Greenland Summer Time
AZOT	-01:00	Azores Time
EGT	-01:00	East Greenland Time
FNST	-01:00	Fernando de Noronha Summer Time
SET	-01:00	Seychelles Time
WAT	-01:00	West Africa Time
AZOST	+00:00	Azores Summer Time
EGST	+00:00	East Greenland Summer Time
GMT	+00:00	Greenwich Mean Time
UTC	+00:00	Universal Coordinated Time
UT	+00:00	Universal Time
WET	+00:00	Western Europe
ZULU	+00:00	Universal Time
Z	+00:00	ISO-8601 Universal Time
BST	+01:00	British Summer Time
CET	+01:00	Central European Time
DNT	+01:00	Dansk Normal Time
FST	+01:00	French Summer Time
MET	+01:00	Middle Europe Time
MEWT	+01:00	Middle Europe Winter Time
MEZ	+01:00	Middle Europe Zone
NOR	+01:00	Norway Standard Time
SWT	+01:00	Swedish Winter Time
WEST	+01:00	Western Europe Summer Time
WEtdST	+01:00	Western Europe Daylight Savings Time
BDST	+02:00	British Double Summer Time
CEST	+02:00	Central European Dayl.Time
CETDST	+02:00	Central European Dayl.Time
EET	+02:00	Eastern Europe, USSR Zone 1
FWT	+02:00	French Winter Time
IST	+02:00	Israel Time
MEST	+02:00	Middle Europe Summer Time
MEtdST	+02:00	Middle Europe Daylight Time
SST	+02:00	Swedish Summer Time
BT	+03:00	Baghdad Time
EAT	+03:00	East Africa Time
EAT	+03:00	Indian Antananarivo Time
EEST	+03:00	Eastern Europe Summer Time
EEtdST	+03:00	Eastern Europe Daylight Time
HMT	+03:00	Hellas Mediterranean Time
MSK	+03:00	Moscow Time
IRT	+03:30	Iran Time
IT	+03:30	Iran Time
AMT	+04:00	Armenia Time (Yerevan)
AZT	+04:00	Azerbaijan Time
EAST	+04:00	Indian Antananarivo Savings Time
GET	+04:00	Georgia Time
MSD	+04:00	Moscow Summer Time
MUT	+04:00	Mauritius Island Time
RET	+04:00	Reunion Island Time
SCT	+04:00	Mahe Island Time
AFT	+04:30	Kabul Time
AMST	+05:00	Armenia Summer Time (Yerevan)
AZST	+05:00	Azerbaijan Summer Time
GEST	+05:00	Georgia Summer Time
IOT	+05:00	Indian Chagos Time
KGT	+05:00	Kyrgyzstan Time
MVT	+05:00	Maldives Island Time
PKT	+05:00	Pakistan Time
TFT	+05:00	Kerguelen Time
TJT	+05:00	Tajikistan Time
TMT	+05:00	Turkmenistan Time
UZT	+05:00	Uzbekistan Time
YEKT	+05:00	Yekaterinburg Time
NPT	+05:45	Nepal Standard Time
ALMT	+06:00	Almaty Time
BDT	+06:00	Dacca Time
BTT	+06:00	Bhutan Time
DUSST	+06:00	Dushanbe Summer Time
KGST	+06:00	Kyrgyzstan Summer Time
LKT	+06:00	Lanka Time
MAWT	+06:00	Mawson, Antarctica
NOVT	+06:00	Novosibirsk Standard Time
OMST	+06:00	Omsk Time
UZST	+06:00	Uzbekistan Summer Time
YEKST	+06:00	Yekaterinburg Summer Time
CCT	+06:30	Indian Cocos (Island) Time
MMT	+06:30	Myanmar Time
ALMST	+07:00	Almaty Savings Time
CVT	+07:00	Christmas Island Time (Indian Ocean)
CXT	+07:00	Christmas Island Time (Indian Ocean)
DAVT	+07:00	Davis Time (Antarctica)
ICT	+07:00	Indochina Time
JAVT	+07:00	Java Time
KRAST	+07:00	Krasnoyarsk Summer Time
NOVST	+07:00	Novosibirsk Summer Time
OMSST	+07:00	Omsk Summer Time
WAST	+07:00	West Australian Std Time
JT	+07:30	Java Time
AWST	+08:00	Western Australia
BNT	+08:00	Brunei Darussalam Time
BORT	+08:00	Borneo Time (Indonesia)
CCT	+08:00	China Coast Time
HKT	+08:00	Hong Kong Time
IRKT	+08:00	Irkutsk Time
KRAT	+08:00	Krasnoyarsk Standard Time
MYT	+08:00	Malaysia Time
PHT	+08:00	Phillipine Time
ULAT	+08:00	Ulan Bator Time
WADT	+08:00	West Australian DST
WST	+08:00	West Australian Standard   Time
MT	+08:30	Moluccas Time
AWSST	+09:00	Western Australia Time
IRKST	+09:00	Irkutsk Summer Time
JAYT	+09:00	Jayapura Time (Indonesia)
JST	+09:00	Japan Std Time, USSR Zone 8
KST	+09:00	Korea Standard Time
PWT	+09:00	Palau Time
ULAST	+09:00	Ulan Bator Summer Time
WDT	+09:00	West Australian DST
YAKT	+09:00	Yakutsk Time
ACST	+09:30	Central Australia
CAST	+09:30	Central Australian ST
SAST	+09:30	South Australian Std Time
SAT	+09:30	South Australian Std Time
AEST	+10:00	Australia Eastern Std Time
DDUT	+10:00	Dumont-d'Urville Time (Antarctica)
EAST	+10:00	East Australian Std Time
EST	+10:00	Australia Eastern Std Time
GST	+10:00	Guam Std Time, USSR Zone 9
KDT	+10:00	Korea Daylight Time
LIGT	+10:00	From Melbourne, Australia
MPT	+10:00	North Mariana Islands Time
PGT	+10:00	Papua New Guinea Time
trUK	+10:00	Truk Time
VLAT	+10:00	Vladivostok Time
YAKST	+10:00	Yakutsk Summer Time
YAPT	+10:00	Yap Time (Micronesia)
ACSST	+10:30	Central Australia Time
CADT	+10:30	Central Australian DST
CST	+10:30	Australia Central Std Time
LHST	+10:30	Lord Howe Standard Time, Australia
SADT	+10:30	South Australian Daylight Time
AESST	+11:00	Eastern Australia
LHDT	+11:00	Lord Howe Daylight Time, Australia
MAGT	+11:00	Magadan Time
NCT	+11:00	New Caledonia Time
PONT	+11:00	Ponape Time (Micronesia)
VLAST	+11:00	Vladivostok Summer Time
VUT	+11:00	Vanuata Time
ANAT	+12:00	Anadyr Time (Russia)
CKT	+12:00	Cook Islands Time
GILT	+12:00	Gilbert Islands Time
IDLE	+12:00	International Date Line, East
KOST	+12:00	Kosrae Time
MAGST	+12:00	Magadan Summer Time
MHT	+12:00	Kwajalein Time
NZST	+12:00	New Zealand Standard Time
NZT	+12:00	New Zealand Time
PETT	+12:00	Petropavlovsk-Kamchatski Time
TVT	+12:00	Tuvalu Time
WAKT	+12:00	Wake Time
WFT	+12:00	Wallis and Futuna Time
CHAST	+12:45	Chatham Island Time
ANAST	+13:00	Anadyr Summer Time (Russia)
NZDT	+13:00	New Zealand Daylight Time
PETST	+13:00	Petropavlovsk-Kamchatski Summer Time
PHOT	+13:00	Phoenix Islands (Kiribati) Time
TOT	+13:00	Tonga Time
CHADT	+13:45	Chatham Island Daylight Time
LINT	+14:00	Line Islands Time (Kiribati)