java.time.Instant - get(INSTANT_SECONDS) Error

This section provides a tutorial example on how to use getLong() to retrieve INSTANT_SECONDS value. Using get() will result an exception.

While testing the get() method, I noticed an unexpected error with the INSTANT_SECONDS field. Here is the test program InstantSecondsError.java:

/* InstantSecondsError.java
 * Copyright (c) HerongYang.com. All Rights Reserved.
 */
import java.time.Instant;
class InstantSecondsError {
   public static void main(String[] a) {
      java.io.PrintStream out = System.out;

      // Instant now = Instant.now();
      Instant now = Instant.parse("2014-04-01T05:48:41.750Z");
      out.println("toString() = " + now.toString());
      out.println("getEpochSecond() = " + now.getEpochSecond());
      out.println("getNano() = " + now.getNano());

      out.println("isSupported(DAY_OF_WEEK) = " + now.isSupported(
         java.time.temporal.ChronoField.DAY_OF_WEEK));
      // Unsupported field: DayOfWeek
      //      out.println("get(DAY_OF_WEEK) = " + now.get(
      //         java.time.temporal.ChronoField.DAY_OF_WEEK));

      out.println("isSupported(NANO_OF_SECOND) = " + now.isSupported(
         java.time.temporal.ChronoField.NANO_OF_SECOND));
      out.println("get(NANO_OF_SECOND) = " + now.get(
         java.time.temporal.ChronoField.NANO_OF_SECOND));

      out.println("isSupported(INSTANT_SECONDS) = " + now.isSupported(
         java.time.temporal.ChronoField.INSTANT_SECONDS));
      // Need to use getLong() to retrieve INSTANT_SECONDS value
      out.println("getLong(INSTANT_SECONDS) = " + now.getLong(
         java.time.temporal.ChronoField.INSTANT_SECONDS));
      // The get() call will throw an exception
      out.println("get(INSTANT_SECONDS) = " + now.get(
         java.time.temporal.ChronoField.INSTANT_SECONDS));
   }
}

When running InstantSecondsError.java with JDK 9 or higher, I got the following output:

herong> java InstantSecondsError.java

toString() = 2014-04-01T05:48:41.750Z
getEpochSecond() = 1396331321
getNano() = 750000000
isSupported(DAY_OF_WEEK) = false
isSupported(NANO_OF_SECOND) = true
get(NANO_OF_SECOND) = 750000000
isSupported(INSTANT_SECONDS) = true
getLong(INSTANT_SECONDS) = 1396331321
Exception in thread "main"
   java.time.temporal.UnsupportedTemporalTypeException:
Unsupported field: InstantSeconds
    at java.base/java.time.Instant.get(Instant.java:567)
    at InstantSecondsError.main(InstantSecondsError.java:29)

Note that the INSTANT_SECONDS value is a "long" value, you need to use getLong() method to retrieve its value. If you use the get() method, you will get an exception. Thanks to G, who pointed out this in a comment on the Web version of this book.

When running InstantSecondsError.java with JDK 1.8, I got an different exception:

herong> \progra~1\java\jdk1.8.0\bin\java InstantSecondsError
toString() = 2014-04-01T05:48:41.750Z
getEpochSecond() = 1396331321
getNano() = 750000000
isSupported(DAY_OF_WEEK) = false
isSupported(NANO_OF_SECOND) = true
get(NANO_OF_SECOND) = 750000000
isSupported(INSTANT_SECONDS) = true
getLong(INSTANT_SECONDS) = 1396331321
Exception in thread "main" java.time.DateTimeException:
 Invalid value for InstantSeconds
 (valid values -9223372036854775808 - 9223372036854775807): 1396331321
at java.time.temporal.ValueRange.checkValidIntValue(ValueRange.java...
at java.time.temporal.ChronoField.checkValidIntValue(ChronoField.java...
at java.time.Instant.get(Instant.java:569)
at InstantSecondsError.main(InstantSecondsError.java:27)

The exception message is very confusing. "(valid values -9223372036854775808 - 9223372036854775807): 1396331321" looks ok to me. The value, 1396331321, is perfectly in the range.

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

 Java Logging

 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

 References

 Full Version in PDF/EPUB