Java 21 OOP vs Clojure FP

This repository contains code examples demonstrating the differences between Object-Oriented Programming in Java 21 and Functional Programming in Clojure.

Overview

The code examples in this repository accompany the article "Object-Oriented Programming in Java 21 vs Functional Programming in Clojure: A Technical Comparison". The examples illustrate the fundamental differences in approach, paradigm, and implementation between these two languages and programming styles.

Repository Structure

├── README.md                 # This file
├── LICENSE                   # MIT License
├── java-examples/            # Java 21 examples
│   ├── pom.xml               # Maven project configuration
│   └── src/
│       └── main/java/
│           ├── fundamentals/ # OOP principles examples
│           ├── patterns/     # Design patterns
│           ├── concurrency/  # Virtual threads examples
│           ├── dataprocessing/ # Data transformation examples
│           ├── webscraper/   # Concurrent web scraper
│           └── ecommerce/    # System design example
├── clojure-examples/         # Clojure examples
│   ├── project.clj           # Leiningen project configuration
│   └── src/
│       └── clojure_examples/
│           ├── fundamentals.clj # FP principles examples
│           ├── patterns.clj     # Functional design patterns
│           ├── concurrency.clj  # Concurrency examples
│           ├── dataprocessing.clj # Data transformation examples
│           ├── webscraper.clj   # Concurrent web scraper
│           └── ecommerce.clj    # System design example
└── docs/
    └── article.md            # The full comparison article

Requirements

Java Examples

• Java 21 or higher
• Maven 3.8+

Clojure Examples

• Clojure 1.11 or higher
• Leiningen 2.9+
• Java 11+ (for JVM)

Getting Started

Running Java Examples

cd java-examples
mvn compile
mvn exec:java -Dexec.mainClass="com.example.dataprocessing.SalesAnalyzer"

Running Clojure Examples

cd clojure-examples
lein run -m clojure-examples.dataprocessing

Key Comparison Points

The examples demonstrate the following comparison points:

1. Fundamental Paradigms

   • OOP principles in Java (encapsulation, inheritance, polymorphism)
   • FP principles in Clojure (pure functions, immutability, first-class functions)

2. Code Structure Approaches

   • State management and data transformation
   • Error/exception handling
   • Concurrency and parallelism
   • Design patterns implementation
   • API design

3. Implementations of Common Problems

   • Data processing with transformations
   • Concurrent web scraping
   • E-commerce system design

4. Technical Considerations

   • Memory usage and garbage collection
   • Performance characteristics
   • Testability approaches
   • Interoperability strategies

5. Language-Specific Features

   • Java's virtual threads vs Clojure's concurrency
   • Java's records vs Clojure's maps
   • Java's pattern matching vs Clojure's destructuring
   • Java's functional interfaces vs Clojure's function composition

License

This project is licensed under the MIT License - see the LICENSE file for details.