Sudoku Game – JavaFX & MVC Architecture

A fully interactive Sudoku application built with JavaFX and organized using the Model–View–Controller (MVC) design pattern.
The application supports multiple difficulty levels, real-time board interaction, file saving/loading of game state, input validation, and hint/check functions.

This project demonstrates clean separation of concerns, object-oriented design, event handling in JavaFX, and serialization of complex game state.

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Features

🎮 Gameplay

• Complete 9×9 Sudoku board with 3×3 sub-grids.
• Pre-filled cells that the user cannot modify.
• Ability to:
  • Insert numbers (1–9)
  • Clear a selected cell
  • Reset all user-entered cells
• Final validation when the last cell is filled.

🤖 Game Logic

• Sudoku generation for three difficulty levels:
  • Easy
  • Medium
  • Hard
• Each difficulty generates a unique randomized Sudoku configuration by:
  • Horizontal and vertical board mirroring
  • Digit permutation (e.g., swap all 1’s with all 2’s)
• Internal model stores:
  • The correct solution
  • Whether a cell is fixed or user-editable
  • The user’s current input

💾 Save & Load

• Save game state to .sudoku files using Java object serialization.
• Load previous games from disk.
• Uses FileChooser for file selection.

🖥️ User Interface (JavaFX)

• Menu bar with:
  • Game: New game, change difficulty
  • File: Save, Load
  • Help: Clear moves, Check board, Hint, About
• Left-side buttons for “Check” and “Hint”.
• Right-side number pad (1–9) for selecting numbers to insert.
• Main 9×9 grid implemented using TilePane.

🧩 Validation & Hint System

• Check: Verifies that all user-entered values are correct so far.
• Hint: Fills one random empty cell with the correct value.

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Architecture

The project follows strict MVC architecture: