🚗 Car Rental System – Java & Database Project

This project was developed as part of my studies at the Department of Digital Systems, University of Piraeus. It involves designing and implementing a Car Rental System using Entity-Relationship modeling, relational database design, and a Java-based CLI application.

📌 Project Description

A car rental company operates a network of branches across various cities in Greece. Each branch offers passenger cars for rent. For each car, the following details are recorded:

• Type (e.g., small, medium, large)

• Number of seats

• Number of doors

• Whether it is automatic or manual

• Fuel type (petrol, diesel, electric, hybrid)

• Rental price per day

• A customer wishing to rent a car provides the following details:

• Pickup location (city and service point)

• Pickup date and time

• Return location (if different from the pickup location)

• Return date and time

• Desired car type (optional)

Once the customer selects a car from the list of available options, the system displays:

• All reservation details

• Total rental cost for the requested period

With the customer’s approval, the system proceeds to finalize the booking by entering:

• First name and last name

• Email address

• Driver’s license number

• Phone numbers (mobile and landline)

📊 Deliverables

1. Entity-Relationship Model (ERD) Design an Entity-Relationship Model (ERM) to represent the system's data and workflow.

Convert the ERM into a Relational Model.

2. Database and Java Application Implement the Relational Database.

Develop a Java application (CLI-based, no graphical interface required).

The application includes a basic menu-driven interface and supports the following operations:

1. ✅ Insert & Update Operations Add or update:

• Cars

• Customers

• Car rentals

2. 🔍 Query Operations

• Retrieve the list of all cars per branch, regardless of availability.

• Retrieve the list of cars currently rented from a specific branch.

Retrieve available cars based on customer input:

• Pickup location and time

• Return location and time

• Optional car type

3. 📄 Booking Execution Perform and register car rental bookings in the system.

4. 🗑️ Deletion Delete cars that are no longer available for rental due to retirement from the fleet.

5. 🛠️ Technologies Used

• Java (Console Application)

• MySQL or PostgreSQL (Relational Database)

• JDBC (Java Database Connectivity)