BicakClc Invoice Management System

Java Swing-based desktop application for managing invoices, products, customers, and related business operations.
Uses Microsoft SQL Server for persistence and supports exporting invoices to Excel (Apache POI).

Features

• Invoice creation with group/sub-group item logic
• Percentage-based discount support
• Per-line labor cost (visible in the app; excluded from Excel export)
• Invoice viewing, filtering, and Excel export (single invoice or all)
• Product & category management
• Customer (company) management with company-name autocomplete
• Favorites management

Tech stack

• Java (Swing) UI
• SQL Server + JDBC (mssql-jdbc)
• Apache POI for Excel export

Project structure

src/
  com/bicakclc/
    main/      Application entry point
    ui/        Swing UI panels (InvoicePanel, InvoiceViewPanel, MainWindow, ...)
    service/   Business logic
    dao/       Data access layer (SQL Server)
    model/     Data models (Invoice, InvoiceItem, Product, Customer, ...)
    util/      Utilities (DatabaseConnection, constants, ...)
  resources/
    sql/       SQL scripts (schema + migrations)
    templates/ Excel template (local, ignored by git)
lib/          External JARs (add to classpath)
bin/          Compiled output (ignored by git)

Setup & run

Prerequisites

• JDK 11+ (the commonly used SQL Server driver for this project targets Java 11)
• Microsoft SQL Server (Express or Standard)
• An IDE (Eclipse / IntelliJ IDEA) or your preferred Java runner

1) Create database tables

Run:

• src/resources/sql/create_invoice_tables.sql

2) Apply migrations (existing DBs)

If you already have a database and you’re updating to a newer version, run:

• src/resources/sql/add_discount_and_missing_fields.sql

3) Configure database connection

The application reads DB settings from config.properties in the repository root (if present).
This file is gitignored (to avoid committing secrets).

1. Copy the example:
   • config.properties.example → config.properties
2. Edit values as needed.

Windows Authentication note:

• If you use integratedSecurity=true, you must place the correct mssql-jdbc_auth-*.dll into your JDK bin/ directory.

4) Add library dependencies

Place the required JARs under lib/ and add them to the classpath (not modulepath).
See lib/README.txt for the expected JAR list.

5) Provide the Excel template (local)

This repository currently ignores *.xlsx, so the template is not committed.
To enable Excel export, make sure the template exists locally at:

• src/resources/templates/inovice_template.xlsx

6) Run the app

Run the main class:

• com.bicakclc.main.BicakClcApplication (src/com/bicakclc/main/BicakClcApplication.java)

Project Architecture

flowchart TD
  User["User"] --> MainWindow["MainWindow (Swing UI)"]

  MainWindow --> InvoicePanel["InvoicePanel"]
  MainWindow --> InvoiceViewPanel["InvoiceViewPanel"]
  MainWindow --> ProductPanel["ProductPanel"]
  MainWindow --> CustomerPanel["CustomerPanel"]
  MainWindow --> FavoritePanel["FavoritePanel"]

  InvoicePanel --> InvoiceService["InvoiceService"]
  InvoicePanel --> PriceCalc["PriceCalculationService"]
  InvoiceViewPanel --> ExcelExport["Excel export (Apache POI)"]

  InvoiceService --> InvoiceDAO["InvoiceDAO"]
  InvoiceService --> InvoiceItemDAO["InvoiceItemDAO"]
  InvoiceService --> CustomerService["CustomerService"]

  CustomerService --> CustomerDAO["CustomerDAO"]
  InvoiceDAO --> DB["SQL Server"]
  InvoiceItemDAO --> DB
  CustomerDAO --> DB

  ExcelExport --> Template["inovice_template.xlsx (local)"]

Loading

Troubleshooting

• ClassNotFoundException / NoClassDefFoundError: verify all JARs are on the classpath.
• DB connection errors:
  • Ensure SQL Server is running and reachable.
  • Verify db.url (and db.username / db.password if using SQL auth) in config.properties.
  • For Windows auth, ensure the mssql-jdbc_auth DLL is installed into the JDK bin/.

Changelog

See CHANGELOG.md.

License

See LICENSE (Non-Commercial Portfolio License).