Software Design Patterns — Assignment 2 (AITU)

Overview

Assignment 2 for the Software Design Patterns course at Astana IT University. The assignment covers two independent tasks, each demonstrating a creational design pattern through a small, self-contained Java program.

• Task 1 — a document-creation system that produces PDF or Word documents without the caller knowing the concrete class.
• Task 2 — a GUI theme system that creates themed UI components (buttons and checkboxes) as a coordinated family, without coupling client code to any specific theme implementation.

Patterns / Concepts Implemented

• Factory Method (documents package) — DocumentFactory.createDocument(String) decides at runtime which concrete Document implementation (PDFDocument or WordDocument) to instantiate. Client code depends only on the Document interface.

• Abstract Factory (themes package) — ThemeFactory is an abstract factory interface with two concrete factories (LightThemeFactory, DarkThemeFactory). Each factory creates a matched pair of Button and Checkbox objects, ensuring UI components always belong to the same theme.

• Interface-based polymorphism — Document, Button, and Checkbox are defined as Java interfaces; concrete classes implement them. Calling code programs to the interface, making it straightforward to add new document types or themes without touching existing code.

Project Structure

src/
├── Main.java                  # IntelliJ default stub (not used)
│
├── documents/
│   ├── Document.java          # Product interface
│   ├── PDFDocument.java       # Concrete product
│   ├── WordDocument.java      # Concrete product
│   ├── DocumentFactory.java   # Factory Method creator
│   └── Main.java              # Entry point for Task 1
│
└── themes/
    ├── Button.java            # Abstract product
    ├── Checkbox.java          # Abstract product
    ├── ThemeFactory.java      # Abstract Factory interface
    ├── LightButton.java       # Concrete product (light)
    ├── LightCheckbox.java     # Concrete product (light)
    ├── LightThemeFactory.java # Concrete factory (light)
    ├── DarkButton.java        # Concrete product (dark)
    ├── DarkCheckbox.java      # Concrete product (dark)
    ├── DarkThemeFactory.java  # Concrete factory (dark)
    └── Main.java              # Entry point for Task 2

How to Run

Via IntelliJ IDEA (recommended)

1. Open the project root in IntelliJ IDEA.
2. To run Task 1, open src/documents/Main.java and click Run.
3. To run Task 2, open src/themes/Main.java and click Run.

Via command line

# Task 1 — Document Creation
javac -d out src/documents/*.java
java -cp out documents.Main

# Task 2 — GUI Theme System
javac -d out src/themes/*.java
java -cp out themes.Main

Expected output for Task 1:

PDF Document created.
Word Document created.

Expected output for Task 2:

Light Button
Light Checkbox
Dark Button
Dark Checkbox

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Adil Ormanov — GitHub