This project is a billing program implemented in Java, with a MySQL database and using JasperReport for invoice generation. The objective is to provide an efficient and user-friendly billing system for managing client and product information, and generating invoices.

The first image shows the buttons for Client, Product, and User.

The second image has the Billing button.

The third image shows buttons for Change User, New User, Help, About Us, and Exit.

The fourth image is the Client Registration window with fields for Document Type, Client ID, Name, Surname, Phone, Email, Country, Birth Date, and Join Date. A DataGridView with registered clients and buttons for Add Client, Delete Client, Edit Client, and Save Changes is also shown.

The fifth image allows the entry of new products with fields for Description, Category, Price, Details, and Quantity. The SKU is auto-incremented, and a DataGridView with the entered product details, and buttons for Add Product, Delete Product, Edit Product, and Save Changes are included.

The sixth image is the User Entry window with fields for ID, Username, Password, Email, Phone, and Description, along with buttons for Add and Clear.

The seventh image is the Billing window, requesting billing details: Client, Product, Quantity, and Date. A DataGridView below shows the added products with their SKU, Description, Price, Details, Quantity, and Total, along with buttons for Add Product, Delete Product, Edit Product, Save Changes, and Generate Invoice.

The eighth image shows the result of generating an invoice, producing a document with the product list using JasperViewer, which can be printed or downloaded as an invoice.