Design Pattern Examples in Kotlin/Native

Model and code examples of GoF Design Patterns for Kotlin/Native.
This project is available for the following objectives:

• To understand GoF Design Pattern examples in Kotlin/Native.
• To understand the mapping between UML model and Kotlin/Native code.
• To try model-driven development (MDD) using Astah and m plus plug-in.

NOTE: The code examples use GTK4 and work on Ubuntu 22 (x86_64) and Fedora 36 (x86_64).

UML model example:

Kotlin/Native code example:

package structuralPatterns.composite
// ˅
// ˄

abstract class FileSystemElement {
    // ˅
    // ˄

    abstract val name: String
        // ˅
        
        // ˄

    abstract val size: Int
        // ˅
        
        // ˄

    // Print this element with the "upperPath".
    abstract fun print(upperPath: String)

    override fun toString(): String {
        // ˅
        return "$name ($size)"
        // ˄
    }

    // ˅
    
    // ˄
}

// ˅

// ˄

Installation on Ubuntu/Fedora

NOTE: The code examples work on Ubuntu 22 (x86_64) and Fedora 36 (x86_64).

UML Modeling Tool

• Download the modeling tool Astah UML/Professional ver.10.0.0 or higher, and install.
• Download m plus plug-in ver.3.0.0-preview or higher, and add it to Astah.
  How to add plugins to Astah

Kotlin/Native Development Environment

• Download and install IntelliJ.
• Run the following command to install GTK4 development libraries.
  Ubuntu 22

  sudo apt install libgtk-4-dev libncurses5 gcc-multilib

  Fedora 36

  sudo dnf install gtk4-devel ncurses-compat-libs

Usage on Ubuntu/Fedora

NOTE: The code examples work on Ubuntu 22 (x86_64) and Fedora 36 (x86_64).

Code Generation from UML

1. Open the Astah file (model/DesignPatternExamplesInKotlinNative.asta).
2. Select model elements on the model browser of Astah.
3. Click the Generate Code button.
   
   The generated code has User Code Area. The User Code Area is the area enclosed by "˅" and "˄". Handwritten code written in the User Code Area remains after a re-generation. View code example.
   For detailed usage of the tools, please see Astah Manual and m plus plug-in tips.

Build and Run

1. Open the project root directory (design-pattern-examples-in-kotlin-native) in IntelliJ.
2. Open Main.kt for the pattern you want to run, and click Run icon in the left gutter.

References

• Gamma, E. et al. Design Patterns: Elements of Reusable Object-Oriented Software, Addison-Wesley, 1994
• Hiroshi Yuki. Learning Design Patterns in Java [In Japanese Language], Softbank publishing, 2004

License

This project is licensed under the Creative Commons Zero (CC0) license. The model and code are completely free to use.

Other Language Examples

C++, C#, Crystal, Go, Java, JavaScript, Python, Kotlin/JVM, Ruby, Scala, Swift, TypeScript