🗂️ Java File System Handler (with MySQL Persistence)

A modular, data-structure-oriented file system implementation in Java, with support for directory and file creation, deletion, and listing — all backed by a MySQL database for persistence.

🚀 Features

• Create and remove files and directories
• In-memory hierarchical structure (FileNode, Directory, File)
• Persistent storage using MySQL (mirrors the file tree)
• Path-based operations (mkdir, touch, ls, rm)
• Clean code structure following OOP and DSA principles

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🏗️ Project Structure

src/
├── FileSystem.java # Core operations and tree management
├── FileNode.java # Abstract base node
├── Directory.java # Represents folders
├── File.java # Represents file nodes
├── pathResolver.java # Normalizes and resolves paths
├── Main.java # Entry point / CLI tester
└── db/
    ├── DatabaseConnection.java # JDBC connector
    ├── FileSystemEntity.java # DB model
    └── FileSystemDAO.java # DAO for DB access

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🧠 Data Structure Overview

• FileNode — abstract base class with name and parent
• Directory — holds a list of child nodes
• File — contains file content (write(), read())
• In-memory tree mimics actual file system hierarchy

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🗃️ MySQL Integration

🧾 SQL Schema

CREATE TABLE file_system (
    id INT PRIMARY KEY AUTO_INCREMENT,
    name VARCHAR(255) NOT NULL,
    type ENUM('FILE', 'FOLDER') NOT NULL,
    parent_id INT DEFAULT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
    FOREIGN KEY (parent_id) REFERENCES file_system(id) ON DELETE CASCADE
);

🛠 Setup Instructions

1. ✅ Install MySQL and create a database:

CREATE DATABASE java_filesystem;
USE java_filesystem;

2. ✅ Run the schema above to create the file_system table.

3. ✅ Insert a root entry (if not using auto-creation in code):

INSERT INTO file_system (id, name, type, parent_id) VALUES (1, '', 'FOLDER', NULL);

⚙️ Configuration 🔌 Set DB Credentials Update dbConn.java:

private static final String URL = "jdbc:mysql://localhost:3306/java_filesystem";
private static final String USER = "your_username";
private static final String PASSWORD = "your_password";

▶️ How to Run Using CLI / Main Compile everything:

javac src/**/*.java

Run

java src/Main

Try CLI example in Main.java:

fs.CreateDirectory("/docs");
fs.CreateDirectory("/docs/projects");
fs.CreateFile("/docs/projects/todo.txt", "Finish MySQL integration");
fs.List("/docs");
fs.RemoveFile("/docs/projects/todo.txt");

bash:

Creating structure...

Listing /docs:
projects
readme.txt

Removing /docs/readme.txt

Listing /docs again:
projects

💡 Design Goals

Keep in-memory tree fast and accurate Use MySQL as persistence layer (survives reboot) Keep modular DAO to support future migration (e.g., to PostgreSQL or file-based DB) Designed for extensibility: add cd, search, or mv with ease

🔮 Future Enhancements

cd command with current working directory context Move (mv) or rename nodes Full-text search Caching or syncing strategy GUI file explorer interface REST API for remote access

🤝 Contributing

Feel free to fork, improve, or open issues. PRs are welcome!

🪪 License

This project is open-source under the MIT License.

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## 🧠 Optional Extras

If you want to:
- Publish this on GitHub, I can help write `.gitignore`, `.editorconfig`, and `.github/workflows`.
- Bundle it as a `.jar` or run via Gradle/Maven.

Want those too?