LocalDateTime utc

LocalDateTime Now UTC Lua Software Cod

LocalDateTime Now UTC. April 13, 2018. java. java-time. kotlin. val now = LocalDateTime.now (ZoneOffset.UTC It stores the billing time as 00:00 UTC. Since that is an instant in time, I think Instant would be the most suitable choice here. You could use a ZonedDateTime as well, but considering that you are probably getting a java.sql.Date from your database, which has a toInstant method already, using Instants is more convenient. You can get an instant from a year, month, day like this: LocalDate ld. LocalDateTime is an immutable date-time object that represents a date-time, often viewed as year-month-day-hour-minute-second. Other date and time fields, such as day-of-year, day-of-week and week-of-year, can also be accessed. Time is represented to nanosecond precision Convert LocalDateTime UTC To System Local Timezone. May 17, 2018. java. java-time. kotlin. And Local Timezone to UTC. Convert UTC to System/Local Timezone. val localDateTime = uctLocalDateTime.atZone (ZoneOffset.UTC).withZoneSameInstant (ZoneId.systemDefault ()).toLocalDateTime () Convert System/Local Timezone to UTC

LocalDateTime := TTimeZone.Local.ToLocalTime(UniversalDateTime); In the other direction use ToUniversalTime. This class appears to be (loosely) modelled on the .net TimeZone class. A word of warning. Do not expect the attempt to account for daylight savings at the time being converted to be 100% accurate. It is simply impossible to achieve that. At least without a time machine. And that's just considering times in the future. Even times in the past are complex. Raymond Chen. LocalDateTime ldt = LocalDateTime.parse(2020-04-06T23:00:00.000); System.out.println(ldt); LocalDate ld = ldt.toLocalDate(); System.out.println(ld); 2020-04-06T23:00 2020-04-06 Converting from LocalDateTime to LocalDate involves no time zone (or UTC offset) whatsoever. The time part is simply discarded and the date part kept unchanged LocalDateTime localDateTime = // whatever e.g. LocalDateTime.now() long time2epoch = localDateTime.toEpochSecond(ZoneOffset.UTC); This seems way shorter that many suggested answers above... Shar

Why “Always use UTC” is bad advice

java - Using localDate with UTC - Stack Overflo

Here we will see how to get current UTC time in java in different ways. How to get Current UTC Time:In older versions of java like before Java8, we can get current UTC time using SimpleDateFormate object like below. Getting UTC time in Java Instant, OffsetDateTime and Joda API LocalDateTime localDateTime = LocalDateTime.ofEpochSecond(timeInSeconds, 0, ZoneOffset.UTC); Now find the examples to convert between Java LocalDateTime and epoch time in detail. Content

LocalDateTime + Time-Zone = Date We can convert LocalDateTime to Date with following methods. 1. Using LocalDateTime.atZone (): It combines this date-time with a given time-zone to create a ZonedDateTime package com.mkyong.date; import java.time.*; public class InstantExample2 { public static void main(String[] argv) { // Hard code a date time LocalDateTime dateTime = LocalDateTime.of(2016, Month.AUGUST, 18, 6, 17, 10); System.out.println(LocalDateTime : + dateTime); // Convert LocalDateTime to Instant, UTC+0 Instant instant = dateTime.toInstant(ZoneOffset.UTC); System.out.println(Instant : + instant); } An object whose Kind property is Local, and whose value is the local time equivalent to the value of the current DateTime object, or MaxValue if the converted value is too large to be represented by a DateTime object, or MinValue if the converted value is too small to be represented as a DateTime object Bei Bedarf konvertiert die LocalDateTime -Eigenschaft das DateTimeOffset Datum und die Uhrzeit des aktuellen-Objekts in das Datum und die Uhrzeit des lokalen Systems. Die Konvertierung ist ein zweistufiger Vorgang: Die-Eigenschaft konvertiert die Uhrzeit des aktuellen- DateTimeOffset Objekts in eine koordinierte Weltzeit (UTC)

Convert java.time.LocalDateTime to java.util.Date. The easiest way of getting a java.util.Date from LocalDateTime is to use an extension to the java.sql.Timestamp — available with Java 8: public Date convertToDateViaSqlTimestamp(LocalDateTime dateToConvert) { return java.sql.Timestamp.valueOf(dateToConvert); } But of course, an alternative solution is using an Instant object, which we obtain. The LocalDateTime represents date-time without a time-zone such as 2019-10-25T12:15:30 whereas Instant is an instantaneous point on the time-line. We can convert between Java LocalDateTime and Instant in following ways. 1. Convert LocalDateTime to Instant using LocalDateTime.toInstant () method. Instant instant = localDateTime.toInstant(ZoneOffset

LocalDateTime (Java Platform SE 8 ) - Oracl

  1. LocalDateTime localDateTime = LocalDateTime.now(); ZonedDateTime zonedDateTime = ZonedDateTime.of(localDateTime, ZoneId.of(UTC)); 3. ZonedDateTime to String. Now, let's convert our ZonedDateTime to a String. For this, we'll use the DateTimeFormatter class. There are a few special formatters that we can use to display time zone data. The full list of formatters can be found here, but we'll.
  2. Hinweis. Sowohl der -Typ als DateTime auch der -Typ weisen einige Einschränkungen bei der DateTimeOffset Darstellung von Zeiten in Zeitzonen auf. Mit seiner Kind-Eigenschaft DateTime kann nur koordinierte Weltzeit (UTC) und die lokale Zeitzone des Systems widerspiegeln. DateTimeOffset spiegelt den Offset einer Zeit von UTC wider, aber nicht die tatsächliche Zeitzone, zu der dieser Offset.
  3. Convert LocalDateTime to seconds since January 1, 1970, 00:00:00 GMT val now = LocalDateTime.now(ZoneOffset.UTC) // LocalDateTime to epoch seconds val seconds = now.atZone(ZoneOffset.UTC).toEpochSecond()) // Epoch seconds to LocalDateTime val newNow = LocalDateTime.ofInstant(Instant.ofEpochSecond(seconds), ZoneOffset.UTC) Convert LocalDateTime to milliseconds since January 1, 1970, 00:00:00.
  4. Internally, LocalDateTime uses a single millisecond-based value to represent the local datetime. This value is only used internally and is not exposed to applications. Calculations on LocalDateTime are performed using a Chronology. This chronology will be set internally to be in the UTC time zone for all calculations
  5. ute etc - it won't be converted into the local system time. Since 2.0.x
  6. The LocalDate represents only the date without time and zone id, while the LocalDateTime represents date with time, so in order to convert LocalDate to LocalDateTime we must append the time with the LocalDate.. LocalDate to LocalDateTime conversion. There are two methods that we can use to convert LocalDate to LocalDateTime. Method atStartOfDay(): This method adds midnight time to the LocalDate
  7. us (4, ChronoUnit.MINUTES); System.

Convert LocalDateTime UTC To System Local Timezone Lua

LocalDateTime (. int tzd, const DateTime & dateTime, bool adjust. ); Deprecated. This function is deprecated and should no longer be used. Creates a LocalDateTime from the UTC time given in dateTime, using the given time zone differential. If adjust is true, adjusts dateTime for the given time zone differential zoneid - localdatetime utc java 8 The entire point to LocalDateTime is to lose time zone info. So we rarely use this class in most apps. Again, the Christmas example. Or another example, Company policy: All our factories around the world take lunch at 12:30 PM. That would be LocalTime, and for a particular date, LocalDateTime. But that has no real meaning, not an actual point on the. LocalDateTime dateTimeOfAfterFiveDays = LocalDateTime.ofEpochSecond(after5,0,ZoneOffset.UTC); LocalDateTime is the wrong class to use here. This class cannot represent a moment. It lacks any concept of time zone or offset-from-UTC. A LocalDateTime holds just a date and a time-of-day, say noon on the 23rd of January this year. But we have no idea if what was intended was noon in Tokyo, noon in. Konvertiere LocalDateTime nach LocalDateTime in UTC.LocalDateTime convertToUtc (LocalDateTime date) KonvertiereIch habe über das Netz gesucht. Aber keine Lösung erhaltenAntworten: -9 für Antwort № 1Sie können versuchenDate in

datetime - How to convert Local time to UTC time in Delphi

  1. To begin with, GMT (which stands for Greenwich Mean Time) is not the same as UTC (which stands for Coordinated Universal Time): GMT is a time zone used in some but not all parts of the world (mainly Europe and Africa). It uses either a 24-hour format or a 12-hour format for display and its based on astronomical observations. UTC is not a time zone. It is a standard which we can use to display.
  2. The LocalDateTime class introduced in Java 8 stores the date and time but not the timezone. So we need something else when developing applications that need to be aware of different timezones. Fortunately, we can use the ZonedDateTime class to represent dates and times with timezone information. The class contains static methods that allow us to perform date conversions and calculations easily
  3. How to change the time based on timezone in LocalDateTime, here i have built a date with Time zone as EST, now i need to find the UTC of the corresponding time. please help me how to solve this String str = 16Jun2015_153556; DateTimeFormatter formatter = DateTimeFormatter.ofPattern(ddMMMyyyy_HHmmss); formatter.withZone(ZoneId.of(EST5EDT)); LocalDateTime dateTime = LocalDateTime.parse(str.
  4. To convert a UTC timestamp to a local time zone, you can use the following: -- all SQL Server versions declare @utc_date datetime = getdate() select @utc_date as utc_time_zone, dateadd(hh, datediff(hh, getutcdate(), getdate()), @utc_date) as local_time_zone --SQL Server 2016 and later declare @utc_date datetime = getdate() select @utc_date as.
  5. ute-second. Other date and time fields, such as day-of-year, day-of-week and week-of-year, can also be.
  6. In this tutorial we will learn how to format java 8 date time types (Instant, LocalDate, LocalDateTime, Date) to JSON using Jackson and Spring Boot 2. Gradle dependencies First of all we need to create a new Spring Boot 2.2.0 based project
SimpleDateFormat 사용법 및 UTC 관련

java - LocalDate and LocalDateTime in a server which runs

Video: datetime - How to get milliseconds from LocalDateTime in

- Java 8 - Convert Date to LocalDate and LocalDateTime. Java Tutorials. Java 16 (Latest) Java 15; Java 14; Java 13; Java 12; Java 11 (LTS) Java 8 (LTS) Java IO / NIO; Java JDBC; Java JSON; Java CSV; Java XML ; Spring Boot; JUnit 5; Maven; Misc; Java 8 - Convert Date to LocalDate and LocalDateTime. By mkyong | Last updated: February 5, 2020. Viewed: 167,507 | +236 pv/w. Here is the code to. Add UTC Timezone to naive datetime. In other words, attach Timezone information to datetime objects that were created without timezone information, without adjusting the time. from datetime import datetime, timezone # this is a naive datetime without timezone information naive_dt = datetime. now () naive_dt # datetime.datetime(2021, 1, 3, 18, 33, 50, 631654) dt_with_tz = naive_dt. replace. UTC stands for Universal Time. CET is known as Central European Time. CET is 2 hours ahead of UTC. So, when it is it will be . Other conversions: UTC to Hong Kong Time, UTC to Melbourne Time, UTC to Copenhagen Time, UTC to Austin Time. Getting Started. 1 Add locations (or remove, set home, order) 2 Mouse over hours to convert time at a glance 3 Click.

Blazor: Anzeige DB-UTC-Zeiten in lokaler Benutzerzeit. Ich habe ein Blazor (Server) Projekt, welches das Entity Framework verwendet. Es ist möglich, gewisse Entitäten zu teilen, sprich mehrere Benutzer haben z.B Rechte auf ein Entry. Ein Entry hat also nicht direkt ein Benutzermapping (Creator Mapping ist aber da) Eine Zeitzone definiert die Zeitdifferenz der Ortszeit zur koordinierten Weltzeit (UTC) sowie die Regeln zur Sommer- und Winterzeitumstellung. Traditionell seit Java 1.1 kapselt die Klasse java.util.TimeZone diese Informationen. Zur Repräsentation von Datum und Zeit inklusive der Zeitzoneninformation dient ein Objekt vom Typ Calendar System.out.println(Time stamp : + timestamp_object); } } Output : Local Date Time : 2020-11-18T23:49:33.175092900. Time stamp : 2020-11-18 23:49:33.1750929. As mentioned above, output can subject to change based on the time code compiled. That's all about how to convert LocalDateTime to Timestamp in Java

java - JPA Model Class for field TIMESTAMP WITHOUT TIME

Solved: How Can I Get the Current Date and Time in UTC or

  1. Java example to format LocalDateTime instance to String using DateTimeFormatter class.. 1. Format LocalDateTime to String // Get current date time LocalDateTime currentDateTime = LocalDateTime.now(); // Inbuilt format static DateTimeFormatter formatter = DateTimeFormatter.ISO_DATE_TIME; // Custom format //DateTimeFormatter formatter = DateTimeFormatter.ofPattern(yyyy-MM-dd HH:mm:ss.
  2. In my current Java project, I'm using hibernate to persist a Java LocalDateTime to an Oracle DATE type column. Out of the box, everything seems to work well, but when the amount of data in the.
  3. We know the time zone of the source data: UTC. Edited by ashleedawg Tuesday, April 17, 2018 9:13 PM; Tuesday, April 17, 2018 9:13 PM. text/html 4/17/2018 9:17:47 PM ashleedawg 0. 0. Sign in to vote. Using the difference between GETUTCDATE() and GETDATE() won't work if the server time is UTC time and/or the query is not run locally. The destination time zone would need to be specified. Tuesday.
java - Setting time in UTC in the HTTP request - Stack

LocalDateTime! = UTC Moment. A LocalDateTimeist keine wirkliche Datum-Zeit, ist es nicht auf die Zeitlinie gebunden. Es hat keine wirkliche Bedeutung , bis Sie es in eine Zeitzone einzustellen , um einen Punkt auf der Zeitlinie zu bestimmen, einen Moment. Der Code, LocalDateTime utcTimemit Ihrer Wahl von Variablennamen, zeigt Sie eine lokale Datum-Zeit verschmelzt haben mit einem Wesen. The LocalDate represents only the date without time and zone id, while the LocalDateTime represents date with time, so in order to convert LocalDate to LocalDateTime we must append the time with the LocalDate.. LocalDate to LocalDateTime conversion. There are two methods that we can use to convert LocalDate to LocalDateTime. Method atStartOfDay(): This method adds midnight time to the LocalDate

Localdate timezone - riesen auswahl an größen & passformen

Methods of Java LocalDateTime. It is used to format this date-time using the specified formatter. It is used to return a copy of this LocalDateTime with the specified number of days subtracted. It is used to obtain the current date-time from the system clock in the default time-zone. It is used to obtain an instance of LocalDateTime from a date. Spring Daten für Apache Cassandra konvertiert java.time.LocalDateTime in UTC Das Problem ist, dass irgendwo entlang der Linie, etwas behandelt diese LocalDateTime Objekte, als ob sie in der Zeitzone meines Servers sind, und sie in UTC Zeit versetzen, wenn sie sie in der Datenbank speichert Java 8 - Datum in LocalDate und LocalDateTime konvertieren Java 8 - Datum in LocalDate und LocalDateTime konvertieren Java 8 - TemporalAdjusters Beispiele Java - So erhalten Sie die aktuelle Datumszeit Struts 2 Beispiel für Datentimepicker Java - So erhalten Sie die aktuelle Datumszeit So vergleichen Sie Datumsangaben in Jav

Java 8 - Parse string to date-time in UTC (or GMT

Add a Timezone to LocalDateTime with ZonedDateTime in Java

MARCH, 18, 13, 45 ); ZonedDateTime zdt2 = dateTime. atZone ( romeZone ); // LocalDateTime + ZoneId Instant instant = Instant. now (); ZonedDateTime zdt3 = instant. atZone ( romeZone ); Java 8 with Time Zones using Offset from UTC. Another common way to express a time zone is to use a fixed offset from UTC/Greenwich OffsetDateTime LocalDateTime + exact offset from UTC ZonedDateTime LocalDateTime + TimeZone + exact offset from UTC but Components of a ZonedDateTime may become inconsistent if it is stored for a long time. kotlinx.datetime Operations on temporal types. Duration between Instants Build started now t Duration. Duration between Instants Build started Instant now Instant t Duration val duration. kotlinx-datetime. A multiplatform Kotlin library for working with date and time. See Using in your projects for the instructions how to setup a dependency in your project.. Design overview. There are a few guiding principles in the design of kotlinx-datetime.First of all, it is pragmatic, focused on the most common problems developers face every day (pun intended) when working with dates and. The LocalDateTime class, introduced in Java 8 new date and time API, represents both local date and time without timezone in ISO-8601 format (yyyy-MM-ddTHH:mm:ss).It is a description of the date, as used for birthdays, combined with the local time as seen on a wall clock. LocalDateTime is the most commonly used class from Java 8 new data and time API to handle dates and times together

LocalDateTime is an immutable date-time object that represents a date-time, often viewed as year-month-day-hour-minute-second. Other date and time fields, such as day-of-year, day-of-week and week-of-year, can also be accessed. Time is represented to nanosecond precision. For example, the value '2nd October 2007 at 13:45.30.123456789' can be stored in a LocalDateTime. This class does not store. When you retrieve a DateTime value using the DateTimeOffset.LocalDateTime property, the property's get accessor first converts the DateTimeOffset value to UTC, then converts it to local time by calling the ToLocalTime method. This means that you can retrieve a value from the DateTimeOffset.LocalDateTime property to perform a time zone conversion at the same time that you perform a type conversion LocalDateTime. A LocalDateTime represents a date-time with no time zone in the ISO-8601 calendar system, such as '2007-12-03T10:15:30'.. Create a LocalDateTime instance // obtain the current date and time in the system default time zone, e.g. '2016-02-26T10:29:05.743' LocalDateTime.now(); // obtain the current date and time in the UTC time zone LocalDateTime.now(ZoneOffset.UTC); // obtain an. Java 8 Date Time API consists of following packages. java.time: This is the base package of the new Java Date Time API. All the major base classes are part of this package, such as LocalDate, LocalTime, LocalDateTime, Instant, Period, Duration, etc. All of these classes are immutable and thread-safe

DateTime.ToLocalTime Methode (System) Microsoft Doc

LocalDateTime localDateTime = LocalDateTime. ofEpochSecond (timeInSeconds, 0, ZoneOffset. UTC); 现在找到在Java LocalDateTime和纪元时间之间转换的详细例子。 1. LocalDateTime 转 Epoch. 将 LocalDateTime 转换为纪元秒或毫秒是从 1970-01-01T00:00:00Z 开始到给定本地日期时间的时间计算。 找到代码 Java LocalDateTime 和 Instant 互相转换1. LocalDateTime 转 Instant1.1 使用 LocalDateTime.toInstant() 将LocalDateTime 转化为 Instant1.2 使用 LocalDateTime.toEpochSecond() 和 Instant.ofEpochSecond() 将LocalDateTime 转化为 Instant2. Instant 转 LocalDateTime2. Message view « Date » · « Thread » Top « Date » · « Thread » From: nic...@apache.org: Subject [09/23] zest-java git commit: ZEST-124 - Replaced Joda Time API with Java Time API, and I also removed the java.util.Date support and all uses except where required when interfacing with other systems OffsetDateTime now = OffsetDateTime.now(ZoneOffset.UTC); System.out.println(now)

Java 8 - ZonedDateTime examples - Mkyong

Convert LocalDateTime to LocalDateTime in UTC. Timezone? LocalDateTime does not store any information about the time-zone, it just basically holds the values of year, month, day, hour, minute, second, and LocalDateTime does not contain Zone information. ZonedDatetime does. If you want to convert LocalDateTime to UTC, you need to wrap by ZonedDateTime fist. You can convert like the below. This. Convert to UTC/ISO. Maybe the most common functionality one would be looking for while working with dates. To convert any date to ISO format, all you need to do is: new Date('07/29/2019 04:00:00').toISOString(); // 2019-07-28T22:30:00.000Z So assuming we want to ISO format of Date: 29th July, 2019 04:00 o'cloc Use case: All of the timestamp fields in our database are really modeling a java.time.Instant, but since jooq gives LocalDateTime instead, we pretend that now() is LocalDateTime.now(Clock.systemUTC()). It becomes a bigger deal when we tr.. Convertiți LocalDateTime la LocalDateTime în UTC. LocalDateTime convertToUtc(LocalDateTime date) { //do conversion } Am căutat peste rețea. java utc java-

Java8 for AndroidQual é a diferença entre Instant e LocalDateTime?

LocalDateTime now() Method in Java with Examples

LocalDateTime localDateTimeBeforeDST = LocalDateTime .of(2018, 3, 25, 1, 55); assertThat(localDateTimeBeforeDST.toString()) .isEqualTo(2018-03-25T01:55); We can observe how a LocalDateTime is conforming to the ISO8601 profile, a standard and widely adopted date-time notation We create LocalDateTime instances using one of the of*() methods where we specify the date and time separately: val beginning = LocalDate.of(1939, 9, 1) val dateTime = LocalDateTime.of(beginning, LocalTime.of(10, 0)) If we want to set the time at the very beginning of the day, we can use the atStartOfDay() method. Another method, which allows us to take a date and attach a time to it, is. The LocalDateTime class represents the date-time,often viewed as year-month-day-hour-minute-second and has got no representation of time-zone or offset from UTC/Greenwich.. The local part of the name refers to the local time-line. LocalDateTime class supports nanosecond precision. For example, the value 2nd October 2007 at 13:45.30.123456789 can be stored in a LocalDateTime Java 8 LocalDateTime class represents a date without associated timezone information. Learn to convert a date in string to LocalDateTime object in Java 8.. 1. String to LocalDateTime example - default and custom patterns. Java example to convert a string into LocalDateTime using LocalDateTime.parse() method. //Default pattern LocalDateTime today = LocalDateTime.parse(2019-03-27T10:15:30.

How to get Current UTC Time in Java - onlinetutorialspoin

Convert a Java Calendar (at UTC) to LocalDateTime. Parameters: date - the date Returns: LocalDateTime instance; getExcelDate public static double getExcelDate(java.time.LocalDate date) Given a LocalDate, converts it into a double representing its internal Excel representation, which is the number of days since 1/1/1900. Fractional days represent hours, minutes, and seconds. Parameters: date. An OffsetDateTime is a LocalDateTime and a UTC offset, two pieces of information. An Instant is just a single piece of information. When combined, it's impossible to restore an Instant to its constituent parts, without adding extra information. We need to store the two pieces of information separately, because we almost always want to show our users the local date time. That's the thing.

Convert between Java LocalDateTime and Epoc

Obtains an instance of LocalDateTime from an Instant and zone ID. This creates a local date-time based on the specified instant. First, the offset from UTC/Greenwich is obtained using the zone ID and instant, which is simple as there is only one valid offset for each instant. Then, the instant and offset are used to calculate the local date-time. LocalDateTime atTime(int hour, int minute, int second, int nanoOfSecond) The method atStartOfDay() returns a LocalDateTime formed from given date at the time of midnight, 00:00, at the start of given date. For all other methods, we provide the specific time in method arguments. hour - the hour-of-day to use, from 0 to 23; minute - the minute-of-hour to use, from 0 to 59; second - the. static LocalDateTime now(): This method is used to call the default date and time from the default time zone, which is the current time zone. In this article, with the help of coding examples, we will see the five major functions used in the Java programming language. Examples of Java LocalDateTime . Examples of java localdatetime are: Example #1. In the first coding example, we will witness. An overview starting with some basic classes of the Java 8 package: Instant, LocalDate, LocalTime, and LocalDateTime. to create the appropriate Instant we have to convert the time to UTC, this. This returns a LocalDateTime formed from this date at the specified hour, minute, second and nanosecond. The individual time fields must be within their valid range. All possible combinations of date and time are valid. Parameters: hour - the hour-of-day to use, from 0 to 23 minute - the minute-of-hour to use, from 0 to 59 second - the second-of-minute to represent, from 0 to 59 nanoOfSecond.

C# Sharp Exercises: Converts current DateTime object to

LocalDateTime plusDays(long days) - Returns a copy of this LocalDateTime with the specified number of days added. LocalDateTime plusHours(long hours) - Returns a copy of this LocalDateTime with the specified number of hours added. LocalDateTime plusMinutes(long minutes) - Returns a copy of this LocalDateTime with the specified number of minutes added In this post, we look at date and time APIs introduced in Java 8, specifically the LocalDate, LocalTime, and LocalDateTime APIs, which are timezone independent LocalDateTime dateTime = LocalDateTime.ofInstant(new Date().toInstant(), ZoneId.systemDefault()); To convert back to a date, we can simply use the Instant that the Java 8 time type represents. One. I currently use the following to get a local datetime from a UTC datetime: SET @offset = DateDiff(minute, GetUTCDate(), GetDate()) SET @localDateTime = DateAdd(minute, @offset, @utcDateTime) My problem is that if daylight savings time occurs between GetUTCDate() and @utcDateTime, the @localDateTime ends up being an hour off For example, the existing classes (such as java.util.Date and SimpleDateFormatter) aren't thread-safe, leading to potential concurrency issues for users—not something the average developer would expect to deal with when writing date-handling code.. Some of the date and time classes also exhibit quite poor API design. For example, years in java.util.Date start at 1900, months start at 1. The mapping is unambiguous in the UTC to local direction, but the reverse is not true: when the offset changes, usually due to a Daylight Saving transition, the change either creates a gap (a period of local time which never occurs in the time zone) or an ambiguity (a period of local time which occurs twice in the time zone)