Modern Java: From 8 to 25 and Beyond

Comprehensive examples and demonstrations of Java features from Java 8 through Java 25, showcasing the evolution of the Java language and platform.

🚀 What's Included

• Practical Code Examples - Real-world demonstrations of modern Java features
• Comprehensive Test Suite - 160+ tests covering all major functionality
• Workshop Presentation - Complete slide deck covering Java evolution (slides.md)
• Java Tier List Presentation - Feature ranking and discussion format (slides-java-tier-list.md)
• Workshop Exercises - Hands-on labs with complete solutions (workshop-exercises.md)
• Data-Oriented Programming - Examples of records, sealed classes, and pattern matching working together

🎯 Key Features Covered

Java 8 - The Functional Revolution

• Lambda expressions and method references
• Stream API with advanced collectors
• Optional for null safety
• Default and static methods in interfaces
• CompletableFuture for async programming

Java 9-11 - Platform Maturity

• JShell (Java REPL)
• Collection factory methods (List.of(), Map.of())
• Local variable type inference (var)
• HTTP Client API
• String enhancements (isBlank(), strip(), repeat())

Java 12-17 - Language Evolution

• Text blocks for multi-line strings
• Records for immutable data classes
• Pattern matching for instanceof
• Switch expressions with yield
• Sealed classes for controlled inheritance

Java 18-21 - Modern Features

• Simple web server (jwebserver)
• Virtual threads for scalable concurrency
• Sequenced collections
• Pattern matching in switch
• Enhanced pattern matching with guards

Java 22-25 - Cutting Edge

• Unnamed variables with _
• Primitive types in patterns (preview)
• Scoped Values (finalized in Java 25)
• Foreign Function & Memory API

🛠️ Build Requirements

• Java 24 - Latest features and compatibility with preview features enabled
• Gradle 8.14.3 - Modern build tooling with Java 24 support
• JUnit 5.13.3 - Modern testing framework
• SonarCloud - Code quality analysis configured for educational code standards

🏃‍♂️ Quick Start

# Clone the repository
git clone https://github.com/kousen/java_latest.git
cd java_latest

# Run all tests
./gradlew test

# Run a specific example
./gradlew run

# Generate code coverage report
./gradlew jacocoTestReport

📊 Running the Presentation

The repository includes a comprehensive Slidev presentation:

# Install dependencies for PDF export
npm install

# Start the presentation
npx slidev slides.md

# Export to PDF
npx slidev export slides.md --format pdf

🎓 Learning Path

For Self-Study

1. Start with Java 8 - ProcessDictionaryV2.java showcases functional programming
2. Explore Records - See Person.java, Customer.java for data classes
3. Pattern Matching - Check UseShapes.java for modern control flow
4. Virtual Threads - VirtualThreadsDemo.java for scalable concurrency
5. Data-Oriented Programming - Combine records, sealed classes, and pattern matching

For Workshops

1. Review the slides - slides.md provides comprehensive coverage
2. Work through exercises - workshop-exercises.md contains hands-on labs
3. Check solutions - Complete implementations in exercises.solutions package
4. Practice with examples - Explore the main codebase for real-world patterns

📚 Key Examples

• ProcessDictionaryV2 - Comprehensive Stream API showcase
• astro package - HTTP Client with Result pattern (sealed interfaces)
• shapes package - Sealed classes with pattern matching
• VirtualThreadsDemo - Modern concurrency patterns

🧪 Testing

# Run all tests
./gradlew test

# Run tests for a specific package
./gradlew test --tests "*interfaces*"

# Run workshop solution tests
./gradlew test --tests "exercises.solutions.*"

# Run with coverage
./gradlew test jacocoTestReport

📈 Code Coverage

JaCoCo reports are generated in build/reports/jacoco/test/html/index.html

📖 Additional Resources

• Modern Java Recipes by Kenneth Kousen
• Java Enhancement Proposals (JEPs)
• Java Almanac

👨‍💻 Author

Kenneth Kousen

• Website: kousenit.com
• Newsletter: Tales from the jar side
• Social: @kenkousen

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This repository is actively maintained and updated with the latest Java features as they become available.