Thursday, 31 July 2025

Java LTS Versions Compared: Java 8 vs 11 vs 17 vs 21

 Java has come a long way since Java 8, and with each Long-Term Support (LTS) release, the language and platform have evolved significantly. Whether you're a developer, architect, or team lead, understanding the differences between Java LTS versions can help you choose the right version for your project.

In this blog post, we'll compare the major LTS versions: Java 8, 11, 17, and 21 — highlighting their key features, improvements, and what makes each version special.


☕ Java 8 (LTS) — March 2014

Major Features:

  • ✅ Lambda Expressions (functional programming)

  • ✅ Streams API

  • ✅ Default Methods in Interfaces

  • java.time package (modern date/time API)

  • ✅ Optional<T> to reduce null checks

  • ✅ CompletableFuture for async programming

🔍 Why it matters: Java 8 was a revolution — introducing functional-style programming and new APIs that changed how Java is written.


☕ Java 11 (LTS) — September 2018

Major Features:

  • ✅ Local-variable syntax for lambdas

  • ✅ New HTTP Client (supports HTTP/2)

  • ✅ New String methods: isBlank(), lines(), repeat()

  • ✅ File I/O improvements: readString(), writeString()

  • ✅ Single-file source-code launcher: java Hello.java

  • ❌ Removed outdated modules: CORBA, Java EE

🔍 Why it matters: Java 11 brought performance gains and cleaner syntax, making it a solid upgrade target from Java 8.


☕ Java 17 (LTS) — September 2021

Major Features:

  • ✅ Sealed Classes – Control class inheritance

  • ✅ Pattern Matching for instanceof

  • ✅ Records – Concise data classes

  • ✅ Switch Expressions – More powerful and expressive

  • ✅ Text Blocks – Multiline strings with ease

  • ✅ New Random Number Generators API

🔍 Why it matters: Java 17 improves readability, reduces boilerplate, and introduces more expressive language features.


☕ Java 21 (LTS) — September 2023

Major Features:

  • ✅ Virtual Threads – Lightweight threads for high concurrency (Project Loom)

  • ✅ Pattern Matching for switch (Finalized)

  • ✅ Structured Concurrency – Simplified thread orchestration

  • ✅ Record Patterns – Pattern matching with records

  • ✅ Sequenced Collections – Ordered collection APIs

  • ✅ Scoped Values (Preview) – Better than thread-local

  • ✅ Simpler main methods with unnamed classes (Preview)

🔍 Why it matters: Java 21 is a game-changer for scalability and concurrency, especially in cloud-native and high-performance applications.

Recommendation: For new projects, use Java 21. For existing Java 8 projects, consider upgrading to at least Java 17.

💬 Have you already upgraded to Java 17 or 21? Share your experience in the comments below!