Chapter Summary

What You Learned

• Data-driven testing separates test data from test logic — one method, many data sets.
• TestNG @DataProvider returns Object[][] — each row runs the test once.
• CSV files are the simplest external data source. Use split(",", -1) to keep empty values.
• Apache POI reads Excel files. Always build a getCellValue() helper for type safety.
• ExcelUtils centralizes POI code. Build it once, use everywhere.
• Jackson ObjectMapper parses JSON. Use POJO mapping for complex nested data.
• Properties files hold configuration, not test data. ConfigReader is a singleton.
• System.getProperty() overrides config file values for CI/CD flexibility.
• @Parameters reads from testng.xml. Use @Optional for IDE compatibility.
• dataProviderClass shares DataProviders across test classes. Keep them centralized.
• Most real-world frameworks are hybrid — POM + data-driven + config management.
• Never commit sensitive data to version control. Use environment variables.

Framework Architecture Cheat Sheet