java.time.ZonedDateTime Usage Examples

JDK Tutorials - Herong's Tutorial Examples

∟Java Date-Time API

∟java.time.ZonedDateTime Usage Examples

This section provides a tutorial example on how to use the java.time.ZonedDateTime class to record and manipulate date and time local to specific timezones. Operations on java.time.ZonedDateTime objects respect ISO 8601 calendar rules and local timezone rules.

To test out the java.time.ZonedDateTime class, I wrote the following example program, ZonedDateTimeTest.java:

/* ZonedDateTimeTest.java
 * Copyright (c) HerongYang.com. All Rights Reserved.
 */
import java.time.ZonedDateTime;
import java.time.temporal.ChronoField;
class ZonedDateTimeTest {
   public static void main(String[] a) {
      java.io.PrintStream out = System.out;
      // ZonedDateTime now = new ZonedDateTime(); // not supported

      ZonedDateTime now = ZonedDateTime.now();
      out.println("Current moment of time:");
      out.println("toString() = " + now.toString());
      out.println("getYear() = " + now.getYear());
      out.println("getMonthValue() = " + now.getMonthValue());
      out.println("getDayOfMonth() = " + now.getDayOfMonth());
      out.println("getHour() = " + now.getHour());
      out.println("getMinute() = " + now.getMinute());
      out.println("getSecond() = " + now.getSecond());
      out.println("getNano() = " + now.getNano());
      out.println("getOffset() = " + now.getOffset());
      out.println("getZone() = " + now.getZone());

      ZonedDateTime leap = ZonedDateTime.parse(
         "2012-02-29T12:00:00+01:00[Europe/Paris]");
      out.println();
      out.println("Leap day:");
      out.println("toString() = " + leap.toString());
      ZonedDateTime nextYear = leap.plusYears(1);
      out.println("1 year later:");
      out.println("toString() = " + nextYear.toString());

      ZonedDateTime summer = ZonedDateTime.parse(
         "2014-11-02T01:30:00-04:00[America/Montreal]");
      out.println();
      out.println("Summer hour:");
      out.println("toString() = " + summer.toString());
      ZonedDateTime winter = summer.plusHours(1);
      out.println("1 hour later:");
      out.println("toString() = " + winter.toString());
   }
}

When running ZonedDateTime.java, I got the following output:

herong> java ZonedDateTime.java

Current moment of time:
toString() = 2024-02-19T16:52:03.822422-03:00[America/Buenos_Aires]
getYear() = 2024
getMonthValue() = 2
getDayOfMonth() = 19
getHour() = 16
getMinute() = 52
getSecond() = 3
getNano() = 822422000
getOffset() = -03:00
getZone() = America/Argentina/Buenos_Aires

Leap day:
toString() = 2012-02-29T12:00+01:00[Europe/Paris]
1 year later:
toString() = 2013-02-28T12:00+01:00[Europe/Paris]

Summer hour:
toString() = 2014-11-02T01:30-04:00[America/Montreal]
1 hour later:
toString() = 2014-11-02T01:30-05:00[America/Montreal]

Interesting notes from the output:

"getZone() = America/New_York" tells me that the timezone ID uses the timezone naming system maintained by Internet Corporation for Names and Numbers (ICANN).
The "Leap day" section of the output tells me that operations on ZonedDateTime objects respect the leap year rules specified in the ISO 8601 calendar.
The "Summer hour" section of the output tells me that operations on ZonedDateTime objects also respect local timezone rules like daylight saving time changes.

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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