Ukrainian Tax Calculator

A Java service for calculating Ukrainian taxes, specifically designed for Interactive Brokers income declarations. This service helps calculate personal income tax (ПДФО) and military tax (Військовий збір) based on your income.

Features

• Calculate taxes for Interactive Brokers income:
  • Personal Income Tax (ПДФО) - 18%
  • Military Tax (Військовий збір) - 1.5%
  • Dividend Tax - 9%
  • Foreign Income Tax - 18%
• Generate tax declarations with all required information
• Precise decimal calculations using BigDecimal
• Comprehensive logging
• Input validation and error handling
• Full test coverage

Prerequisites

• Java 21 or higher
• Maven 3.6 or higher

Installation

1. Clone the repository:

git clone [repository-url]
cd [project-directory]

2. Build the project:

mvn clean install

Usage

Basic Usage

// Create tax service instance
UkrainianTaxService taxService = new UkrainianTaxServiceImpl();

// Calculate taxes for income
BigDecimal income = new BigDecimal("10000.00");
Map<UkrainianTaxCategory, BigDecimal> taxes = taxService.calculateInteractiveBrokersTaxes(income);

// Get individual tax amounts
BigDecimal incomeTax = taxes.get(UkrainianTaxCategory.INCOME_TAX);      // 1800.00 (18%)
BigDecimal militaryTax = taxes.get(UkrainianTaxCategory.MILITARY_TAX);  // 150.00 (1.5%)

// Calculate total tax
BigDecimal totalTax = taxService.calculateTotalTax(income);  // 1950.00

Generating Tax Declaration

// Generate tax declaration for specific year
Map<String, Object> declaration = taxService.generateTaxDeclaration(income, 2024);

// Declaration contains:
// - year: 2024
// - income: 10000.00
// - incomeTax: 1800.00
// - militaryTax: 150.00
// - totalTax: 1950.00
// - generatedDate: current date

Tax Categories

The service supports the following tax categories:

Category	Rate	Description
INCOME_TAX	18.0%	Personal Income Tax (ПДФО)
MILITARY_TAX	1.5%	Military Tax (Військовий збір)
DIVIDEND_TAX	9.0%	Dividend Tax
FOREIGN_INCOME_TAX	18.0%	Foreign Income Tax

Configuration

The service uses the following default configuration:

• Decimal places: 2
• Rounding mode: HALF_UP
• Logging: SLF4J with Logback

Testing

Run the tests using:

mvn test

The test suite includes:

• Basic tax calculations
• Total tax calculations
• Tax declaration generation
• Input validation
• Error handling

Logging

The service uses SLF4J with Logback for logging. Log messages include:

• Tax calculation details
• Input validation errors
• Declaration generation events

Error Handling

The service includes validation for:

• Null income values
• Negative income values
• Invalid tax categories

Contributing

1. Fork the repository
2. Create your feature branch
3. Commit your changes
4. Push to the branch
5. Create a new Pull Request

License

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments

• Uses TestNG for testing
• Implements precise decimal calculations using BigDecimal