🎓 CEMS: Campus Event Management System (v1.1)

CEMS is a robust, 3-tier enterprise application designed to streamline the proposal, approval, and registration of academic and extracurricular events across a university campus.

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🏗️ System Architecture (3-Tier)

CEMS utilizes a strict 3-Tier architecture to prevent direct client-to-database communication:

1. Presentation Layer (Client): A lightweight Java Swing desktop application. Features asynchronous network handling (SwingWorker) for non-blocking UI and loading states.
2. Application Layer (API): A Spring Boot RESTful API. Acts as the secure middleman, handling all business logic, validation, transaction rollbacks, and database routing.
3. Data Layer (Database): A TiDB / MySQL relational database structured in 3NF, enforcing data integrity via strict Foreign Key constraints.

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✨ Key Features

• Role-Based Access Control (RBAC): Dedicated portals and permissions for Students, Organizers, and Administrators.
• Event Lifecycle Management: Organizers propose events, Admins approve/reject them, and Students browse and register for active events.
• Smart Capacity Tracking: Real-time venue capacity validation prevents overbooking during student registration.
• Dynamic Timeline Math: The API dynamically calculates whether an event is "Upcoming", "Ongoing", or "Completed" based on real-time server dates.
• Zero-Trust Client: The desktop application contains zero SQL queries and zero database credentials, relying entirely on HTTP requests to the REST API.

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🚀 Installation & Setup

Because CEMS is a distributed application, you will need to run both the API and the Client.

1. The API (Spring Boot)

1. Clone the repository and open the cems-api folder in your IDE.
2. Update the application.properties file with your TiDB/MySQL database credentials.
3. Run ApiApplication.java to start the embedded Tomcat server on localhost:8080.

2. The Client (Java Swing)

1. Open the cems-client folder in your IDE.
2. Navigate to src/utils/HttpUtils.java.
3. Ensure the BASE_URL is pointing to your API (e.g., http://localhost:8080/api for local testing, or your Render URL for production).
4. Compile and run the application.

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🧹 Configuration: Nightly Data Reset (Portfolio Mode)

By default, this API is configured for a public portfolio/demo environment. To prevent database clutter from test users, a Spring Boot @Scheduled cron job runs at exactly 00:00:00 every night.

This job performs a "Scorched Earth" total wipe of all events, venues, departments, and user accounts (except permanent Administrators) while safely respecting Foreign Key constraints.

⚠️ If you are deploying this for real-world campus use, you MUST disable this feature:

1. Open src/main/java/com/cems/api/ApiApplication.java.
2. Remove the @EnableScheduling annotation from the top of the class.
3. (Optional) Delete the DatabaseCleanupService.java file entirely from the services package.

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🛠️ Recent Updates

• Security Upgrade: Deprecated legacy DAO architecture. Removed mysql-connector-java from the client.
• Network Handling: Implemented HttpUtils for standard REST communication (GET, POST, PUT, DELETE).
• UI/UX Enhancement: Wrapped all HTTP calls in SwingWorker threads to prevent UI freezing during network latency.
• Bug Fix (Ghost Sessions): Synchronized client session IDs with database auto-generated IDs by chaining asynchronous login requests immediately after successful account creation.