java.time.LocalDateTime - Local Date and time without Timezone

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∟Java Date-Time API

∟java.time.LocalDateTime - Local Date and time without Timezone

This section describes the java.time.LocalDateTime class that represents a local time in an unspecified timezone expressed in 2 components, ISO 8601 date and time of day.

java.time.LocalDateTime is a class of the Date-Time API introduced in JDK 1.8 that represent a local date and time without knowing the timezone or UTC offset. A java.time.LocalDateTime object does not represent any specific moment of the absolute time. For example, a java.time.LocalDateTime object with a value of "2014-11-28T05:00:00.000" represents the Walmart store opening local time for the Black Friday sale in 2014. "2014-11-28T05:00:00.000" means different times if you travel to difference places outside the local timezone.

The date and time value stored in a java.time.LocalDateTime object has 2 components:

Local-Date - Representing a date in ISO 8601 calendar adjusted to the local time in the given timezone. This component can be expressed as a year, month, and day combination like "2014-04-01".
Local-Time - Representing local time of the day in the given timezone. This component can be expressed as a hour, minute, second and fraction of second combination like "07:48:41.750123456".

Since a LocalDateTime object does not represent a time with full date and time components, it can also be called as a partial date time object.

The java.time.LocalDateTime class is designed mainly for manipulating local times without any specific timezone to support local daily activities, like celebrating New Year Eve at Dec 31, 23:59:59.000 local time. Its operations respects ISO 8601 calendar only.

Main methods offered on the java.time.Instant class are:

of() - A static method returning a LocalDateTime object representing a local time constructed by a given ISO 8601 date and time of day.
ofInstant() - A static method returning a LocalDateTime object representing the local time converted from a given Instant object and a given local timezone.
getYear() - An object method returning the year value of this LocalDateTime object.
getMonthValue() - An object method returning the month-of-year value of this LocalDateTime object.
getDayOfMonth() - An object method returning the day-of-month value of this LocalDateTime object.
getDayOfWeek() - An object method returning the day-of-week value of this LocalDateTime object.
getHour() - An object method returning the hour-of-day value of this LocalDateTime object.
getMinute() - An object method returning the minute-of-hour value of this LocalDateTime object.
getSecond() - An object method returning the second-of-minute value of this LocalDateTime object.
getNano() - An object method returning the Nanosecond-of-Second value of this LocalDateTime object.
get() - An object method returning the value of a given temporal field, NANO_OF_SECOND, SECOND_OF_MINUTE, MINUTE_OF_HOUR, HOUR_OF_DAY, DAY_OF_WEEK, DAY_OF_MONTH, MONTH_OF_YEAR, YEAR, etc. from this LocalDateTime object.
toString() - An object method returning a string representing this LocalDateTime object in ISO 8601 date and time format. Here is an example of toString() output, "2014-04-01T04:41:10.123456789".
plus() - An object method returns a copy of this LocalDateTime object with additional date or time units added. During the operation, ISO 8601 calendar rules are respected.
minus() - An object method returns a copy of this LocalDateTime object with additional date or time units removed. During the operation, ISO 8601 calendar rules are respected.
with() - An object method returns a copy of this LocalDateTime object with a new value set on a specified field and other fields adjusted accordingly. During the operation, ISO 8601 calendar rules are respected.
parse() - A static method returning a LocalDateTime object representing a moment of time constructed by parsing the given character sequence using the ISO 8601 date and time format like "2007-12-03T10:15:30+01:00.123"
now() - A static method returning a LocalDateTime object representing the local time based on the system clock time.

Table of Contents

About This JDK Tutorial Book

JDK (Java Development Kit)

►Java Date-Time API

What Is Date-Time API

java.time.Instant - Representing a Moment of Time

java.time.Instant Usage Examples

java.time.Instant - get(INSTANT_SECONDS) Error

Converting java.util.Date to java.time.Instant

java.time.ZonedDateTime - Calendar and Timezone

java.time.ZonedDateTime Usage Examples

Converting java.util.GregorianCalendar to java.time.ZonedDateTime

java.time.OffsetDateTime - Calendar and UTC Offset

java.time.OffsetDateTime Usage Examples

►java.time.LocalDateTime - Local Date and time without Timezone

Partial Date and Time Objects and Classes

java.time.format.DateTimeFormatter - Date-Time Strings

java.time.Duration - Time Durations

java.time.Duration Usage Examples

java.time.Period - Periods in Days and Months

java.time.Period Usage Examples

Date, Time and Calendar Classes

Date and Time Object and String Conversion

Number Object and Numeric String Conversion

Locales, Localization Methods and Resource Bundles

Calling and Importing Classes Defined in Unnamed Packages

HashSet, Vector, HashMap and Collection Classes

Character Set Encoding Classes and Methods

Character Set Encoding Maps

Encoding Conversion Programs for Encoded Text Files

Socket Network Communication

Datagram Network Communication

DOM (Document Object Model) - API for XML Files

SAX (Simple API for XML)

DTD (Document Type Definition) - XML Validation

XSD (XML Schema Definition) - XML Validation

XSL (Extensible Stylesheet Language)

Message Digest Algorithm Implementations in JDK

Private key and Public Key Pair Generation

PKCS#8/X.509 Private/Public Encoding Standards

Digital Signature Algorithm and Sample Program

"keytool" Commands and "keystore" Files

KeyStore and Certificate Classes

Secret Key Generation and Management

Cipher - Encryption and Decryption

The SSL (Secure Socket Layer) Protocol

SSL Socket Communication Testing Programs

SSL Client Authentication

HTTPS (Hypertext Transfer Protocol Secure)

Outdated Tutorials

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