Vehicle Bidding System

The Web-based Vehicle Bidding System is a comprehensive online marketplace engineered for Lanka Auto Traders (Pvt) Ltd to digitize and optimize second-hand and reconditioned vehicle sales. Built to accommodate buyers, sellers, and administrators within a unified ecosystem, the platform streamlines the bidding process, ensures auction integrity, and facilitates post-auction transactions.

The system features an automated Auction Management engine that manages vehicle listings and bidding schedules. By using Spring's task scheduling, the backend automatically transitions auctions from pending states to active bidding, and then to closure at pre-scheduled times, resolving winners dynamically based on the highest bid recorded in the database.

To prevent bot exploits and sniper bidding, the platform implements an intelligent 'anti-sniping' extension system. If a bid is submitted in the final 30 seconds of an active auction, the engine automatically extends the closing window by 30 seconds. Real-time updates are driven by a WebSocket messaging architecture configured with SockJS and STOMP, pushing bid changes and timer updates instantly to all connected clients. On the client side, dynamic ES6 JavaScript countdown timers update the user interface seamlessly without full-page refreshes, using visual color transitions to reflect time urgency.

Complementing the real-time core, the platform includes structured administration tools with role-based access control (RBAC), allowing Sales Managers and Admin Officers to override timers, manually manage listing approvals, and monitor system metrics. The integration of Spring Security and JPA-managed entity relationships with a Microsoft SQL Server database ensures robust transactional consistency and system security.