TestNG for QA Engineers

What's the TestNG annotation lifecycle?

BeforeSuite → BeforeTest → BeforeClass → BeforeMethod → @Test → AfterMethod → AfterClass → AfterTest → AfterSuite.

How do you parameterise tests in TestNG?

@Parameters with testng.xml, or @DataProvider returning Object[][] for richer data sets.

How do you run tests in parallel?

Set parallel attribute (methods/tests/classes/instances) and thread-count in testng.xml.

Difference between groups and priority?

Groups categorise tests for selective runs (smoke, regression); priority orders execution within a class.

Hard vs soft assertion?

Hard assertions stop the test on failure; soft assertions collect failures and require assertAll() at the end.

What is a retry analyzer?

An IRetryAnalyzer implementation that retries failed tests N times — used carefully to handle transient flake.

How do you use listeners?

Implement ITestListener for events (start/success/failure) and wire via @Listeners or testng.xml — typically used for logging and reports.

dependsOnMethods vs dependsOnGroups?

Method-level vs group-level dependency; dependent tests are skipped if their dependency fails.

TestNG vs JUnit 5?

TestNG wins on built-in parallelism and data-driven features; JUnit 5 wins on modular design and modern Java idioms. Choice usually follows team stack.

How do you integrate TestNG with Maven?

Use surefire-plugin, point at testng.xml or test classes, and bind to the test phase; reports land in target/surefire-reports.