This repository demonstrates modern Java features from Java 10 through Java 25.

• trail/src/Main25.java - Java 25 features demonstration
• trail/src/StreamGatherers25.java - Java 25 Stream Gatherers API examples
• trail/src/Main21.java - Java 21 features demonstration
• trail/src/Main.java - Java 17 and earlier features
• trail/src/Letters.java - Sealed class example
• trail/src/Hash.java - Sealed interface example
• trail/src/English.java - Text blocks and sealed types

• Flexible constructor bodies (JEP 482) - Statements before super() in constructors
• Primitive type patterns (JEP 455) - Pattern matching with primitive types in switch and instanceof
• Stream Gatherers - Custom intermediate stream operations (windowFixed, windowSliding, fold, mapConcurrent)
• Enhanced pattern matching - Primitive patterns in switch expressions with guards

• Record patterns in switch - Pattern matching with records in switch expressions
• Sequenced collections - New collection interfaces with defined ordering (addFirst, addLast, reversed)
• Virtual threads - Lightweight threads for high-throughput concurrent applications

• Sealed classes - Control which classes can extend a class
• Sealed interfaces - Control which classes can implement an interface
• Switch expressions - Enhanced switch with arrow syntax
• Pattern matching with instanceof - Type patterns in instanceof
• var-args - Variable-length argument lists

• Text blocks - Multi-line string literals with proper formatting

• Type inference (var) - Local variable type inference

• Java 21 examples require Java 21 or later
• Java 25 examples require Java 25 or later (or a compatible early-access build)