Java Version Guide

• Flexible constructor bodies — run statements before this()/super() (JEP 513)
• Module import declarations — import module M to pull in a module’s exported packages (JEP 511)
• Compact source files & instance main methods — much smaller “hello world”, great for learning (JEP 512)
• Scoped values standardized — a safer, immutable alternative to thread-locals (JEP 506)
• Still in preview: primitive types in patterns, structured concurrency, stable values

Release notes →

• Stream Gatherers standardized — custom intermediate stream operations (JEP 485)
• Class-File API standardized — parse/generate .class files without ASM (JEP 484)
• Quantum-resistant cryptography: ML-KEM (JEP 496) and ML-DSA (JEP 497)
• Ahead-of-time class loading & linking — faster startup, part of Project Leyden (JEP 483)
• Compact object headers (experimental); the Security Manager is now permanently disabled

Release notes →

• Markdown in Javadoc — write doc comments in Markdown (JEP 467)
• Generational ZGC becomes the default mode (JEP 474)
• Primitive types in patterns, instanceof, and switch (preview)

Release notes →

• Foreign Function & Memory API standardized — call native code and manage off-heap memory, no JNI (JEP 454)
• Unnamed variables & patterns (_) standardized (JEP 456)
• Multi-file source-code programs via java launcher; statements before super() (preview)

Release notes →

• Virtual threads standardized — cheap, massively scalable concurrency (JEP 444)
• Record patterns standardized — destructure records in switch/instanceof (JEP 440)
• Pattern matching for switch standardized (JEP 441)
• Sequenced collections — uniform first/last access (JEP 431)
• Generational ZGC; string templates & unnamed patterns (preview)

Release notes →

• Second previews of virtual threads, record patterns, and pattern matching for switch
• Scoped values (incubator)

Release notes →

• Virtual threads (preview) and structured concurrency (incubator) debut
• Record patterns (preview); pattern matching for switch (preview); FFM API (preview)

Release notes →

• UTF-8 as the default charset everywhere (JEP 400)
• Simple web server (jwebserver) for quick static hosting; code snippets in Javadoc

Release notes →

• Sealed classes standardized — restrict which types can extend/implement (JEP 409)
• New macOS rendering pipeline (Metal); strong encapsulation of JDK internals
• The long-time baseline for Spring Boot 3.x and much of the modern ecosystem

Release notes →

• Records standardized (JEP 395); pattern matching for instanceof standardized (JEP 394)
• Stream.toList(), Unix-domain socket channels, Vector API (incubator)

Release notes →

• Text blocks standardized — multi-line string literals (JEP 378)
• Sealed classes (preview); ZGC and Shenandoah become production-ready

Release notes →

• Records and pattern matching for instanceof debut (preview)
• Switch expressions standardized (JEP 361); helpful NullPointerException messages

Release notes →

• Text blocks (preview); switch expressions (second preview)
• Dynamic CDS archives

Release notes →

• Switch expressions (preview); Shenandoah GC (experimental)
• Compact number formatting

Release notes →

• Standardized HTTP Client (java.net.http) with HTTP/2 and WebSocket (JEP 321)
• var allowed in lambda parameters; run a single source file directly (java Foo.java)
• Flight Recorder open-sourced; new String methods (isBlank, strip, lines, repeat)

Release notes →

• var — local-variable type inference (JEP 286)
• Application class-data sharing; parallel full GC for G1

Release notes →

• Module system (JPMS / Project Jigsaw) (JEP 261)
• JShell (the REPL); collection factory methods (List.of, Map.of); private interface methods

Release notes →

• Lambda expressions and the Stream API — the biggest language shift in Java’s history
• The java.time (JSR-310) date/time API; default methods on interfaces; Optional
• Still widely deployed; the last LTS before the modular era

What’s new in Java 8 →