Which version of Java should be installed?

Agenda#

• What are the available Java versions?
• Why do we have so many Java versions available to download & install?
• Understand the terms LTS and Non-LTS
• Which version of Java should be installed?

What are the available Java versions?#

Java has several versions, each offering new features, improvements, and security updates. Below are some of the key Java versions:

1. Java 1.0 (Released in 1996)
   • The first version of Java, known as "Java 1," introduced the core functionality and syntax of the language.
2. Java 1.1 (Released in 1997)
   • Added new features such as inner classes, JavaBeans, and the event listener model.
3. Java 1.2 (Released in 1998)
   • Introduced the Java 2 Platform, including the Swing GUI toolkit, collections framework, and Java Plug-in.
4. Java 1.3 (Released in 2000)
   • Introduced performance improvements and several minor features like the HotSpot JVM.
5. Java 1.4 (Released in 2002)
   • Introduced features such as regular expressions, logging API, and the assert keyword.
6. Java 5 (1.5) (Released in 2004)
   • Major update with features like generics, metadata annotations, enumerated types, and the for-each loop.
7. Java 6 (1.6) (Released in 2006)
   • Improved performance, introduced the Java Compiler API, and enhanced the Java platform's integration with web services.
8. Java 7 (Released in 2011)
   • Introduced features like the try-with-resources statement, the diamond operator, and improvements in NIO.
9. Java 8 (Released in 2014)
   • A major release with the introduction of lambdas, the Stream API, and the java.time package for modern date-time handling.
10. Java 9 (Released in 2017)
    • Introduced the module system (Project Jigsaw), which helps with better modularization of code.
11. Java 10 (Released in 2018)
    • Introduced local-variable type inference with the var keyword and some performance improvements.
12. Java 11 (Released in 2018)
    • A Long-Term Support (LTS) release with features like HTTP client API, and several deprecated and removed features.
13. Java 12 (Released in 2019)
    • Introduced features such as Shenandoah garbage collector and JVM constants API.
14. Java 13 (Released in 2019)
    • Introduced text blocks and other minor updates.
15. Java 14 (Released in 2020)
    • Added features like records (preview) and the helpful null pointer exception.
16. Java 15 (Released in 2020)
    • Introduced sealed classes (preview) and other minor updates.
17. Java 16 (Released in 2021)
    • Introduced features like pattern matching (preview) and the new native memory tracking.
18. Java 17 (Released in 2021)
    • A Long-Term Support (LTS) release with notable features like the enhanced switch statement and sealed classes.
19. Java 18 (Released in 2022)
    • Introduced features such as simple web server and UTF-8 by default for string handling.
20. Java 19 (Released in 2022)
    • Introduced new features like record patterns (preview) and virtual threads (preview).
21. Java 20 (Released in 2023)
    • Introduced features like virtual threads (final), scoped values, and more improvements.
22. Java 21 (Released in 2023)
    • A Long-Term Support (LTS) release with enhancements in performance, pattern matching, and other language features.

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Java Architecture Before and After Java 11#

Before Java 11#

• Java used to have JDK (Java Development Kit) and JRE (Java Runtime Environment) as two separate parts.
• The JDK included:
  • Java Compiler (javac)
  • Development tools
  • And also the JRE
• The JRE included:
  • Java Virtual Machine (JVM)
  • Core libraries
  • Other runtime components

So earlier, if someone just wanted to run Java programs (not develop), they could install only the JRE.

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After Java 11#

• From Java 11 onwards, the JRE is no longer provided separately.
• Now, only the JDK is available, and it includes everything:
  • Compiler, tools, JVM, and all runtime components.

So after Java 11, you just install the JDK, and you get everything needed to both run and develop Java applications.

Understanding LTS and Non-LTS in Java#

LTS – Long-Term Support#

• LTS stands for Long-Term Support.
• These Java versions are officially supported for a longer time (usually at least 8 years).
• They receive security updates, bug fixes, and performance improvements for many years.
• Best choice for:
  • Enterprises
  • Production environments
  • Stable applications

Examples of LTS versions:

Java 8, Java 11, Java 17, Java 21

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Non-LTS – Non-Long-Term Support#

• Non-LTS versions are interim releases between LTS versions.
• They receive support for a short period (usually 6 months).
• Mostly used by:
  • Developers who want to try new features early
  • For learning or testing

Examples of Non-LTS versions:

Java 9, 10, 12, 13, 14, 15, 16, 18, 19, 20, 22

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Why Choosing the Right Java Version is Important#

If a company chooses Java as its main platform for development, it must choose the right version carefully.

If the company selects a non-LTS version (which has short-term support), it may lose official updates and security patches after a few months.

This can become a problem in the long run, especially for large applications, because:

• Bugs and vulnerabilities won’t get fixed.
• Upgrading frequently can be time-consuming and risky.
• It may break compatibility with tools and frameworks.

That’s why companies usually prefer LTS versions like Java 11, 17, or 21 — to ensure long-term stability and support.

Java Release Pattern Changed by Oracle#

Earlier, Java versions were released irregularly — sometimes a new version came after 4 or more years, which made planning difficult for developers and companies.

Oracle didn’t like this inconsistent pattern, so they introduced a new and predictable release cycle:

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New Java Release Schedule (After Java 9)#

• Every 6 months: A new Non-LTS version is released (Example: Java 10, 12, 13, 14…)
• Every 3 years: A new LTS (Long-Term Support) version is released (Example: Java 11 → Java 17 → Java 21…)

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This change helps developers:

• Get new features faster
• Plan upgrades better
• Use stable LTS versions in production
• Try out non-LTS versions for testing and learning

This predictable release model started from Java 9 (2017) onwards.