If you’re preparing for a QA or automation testing interview, understanding TestNG is a must. It’s one of the most widely used testing frameworks for Java applications, especially in combination with Selenium WebDriver.
Whether you’re a fresher brushing up on the basics or an experienced QA professional revisiting advanced topics, this post covers over 25 TestNG interview questions and answers, from beginner to expert level.
Let’s dive in.
✅ What is TestNG?
TestNG (Test Next Generation) is an open-source automation testing framework inspired by JUnit and NUnit but designed to overcome their limitations and add more powerful features. It supports:
- Annotations
- Parallel test execution
- Flexible test configuration
- HTML reports
- Data-driven testing
🔍 Why is TestNG Important in Interviews?
In many QA interviews, especially those involving Selenium automation, knowledge of TestNG is a core requirement. Hiring managers assess your ability to:
- Structure test scripts
- Use annotations correctly
- Configure test suites
- Handle exceptions and parallelism
- Integrate with tools like Maven, Jenkins, etc.
📚 Basic TestNG Interview Questions
1. What are the advantages of using TestNG over JUnit?
- More annotations (
@BeforeSuite,@AfterSuite, etc.) - Support for parallel testing
- Better reporting features
- Flexible test configuration using
testng.xml - Built-in support for parameterization
2. List some key TestNG annotations.
@BeforeSuite/@AfterSuite@BeforeTest/@AfterTest@BeforeClass/@AfterClass@BeforeMethod/@AfterMethod@Test@Parameters@DataProvider
3. What is the role of testng.xml?
testng.xml is used to:
- Define test suites and test groups
- Configure test execution order
- Pass parameters
- Include or exclude tests
- Enable parallel execution
4. What is the default priority of a TestNG test?
If no priority is defined, TestNG assigns default priority = 0. Tests execute in ascending order of priority.
5. How do you disable a test in TestNG?
Use @Test(enabled = false) to disable a test case temporarily.
🚀 Intermediate TestNG Interview Questions
6. What is @DataProvider in TestNG?
@DataProvider is used for data-driven testing. It supplies data to a test method in the form of a 2D object array.
@DataProvider(name = "loginData")
public Object[][] loginData() {
return new Object[][] {
{"admin", "admin123"},
{"user", "user123"}
};
}
@Test(dataProvider = "loginData")
public void testLogin(String username, String password) {
// test logic here
}
7. Can you run TestNG tests in parallel?
Yes. Parallel test execution is supported in TestNG using parallel and thread-count attributes in testng.xml.
<suite name="ParallelTests" parallel="tests" thread-count="2">
8. How do you pass parameters from testng.xml?
Using @Parameters annotation:
<parameter name="browser" value="chrome"/>
@Parameters("browser")
@Test
public void openBrowser(String browserName) {
// logic to open specific browser
}
9. What are soft assertions in TestNG?
Soft assertions allow test execution to continue even after a failure, unlike hard assertions.
SoftAssert softAssert = new SoftAssert();
softAssert.assertEquals(actual, expected);
softAssert.assertAll(); // reports all failures
10. Explain the TestNG execution order.
TestNG follows this execution order for annotated methods:
@BeforeSuite@BeforeTest@BeforeClass@BeforeMethod@Test@AfterMethod@AfterClass@AfterTest@AfterSuite
💡 Advanced TestNG Interview Questions
11. What is test grouping in TestNG?
You can group related test cases using groups attribute:
@Test(groups = "smoke")
public void test1() {}
Then execute with testng.xml:
<groups>
<run>
<include name="smoke"/>
</run>
</groups>
12. How do you skip a test in TestNG dynamically?
Throw SkipException:
throw new SkipException("Skipping this test case");
13. What is the use of dependsOnMethods?
It defines a dependency between test methods:
@Test
public void login() {}
@Test(dependsOnMethods = {"login"})
public void dashboardTest() {}
14. Can we run only failed test cases in TestNG?
Yes. After execution, TestNG creates a testng-failed.xml file in the test-output folder. You can re-run this file.
15. Explain ITestListener interface.
ITestListener allows logging actions during test execution. It includes methods like:
onTestStart()onTestSuccess()onTestFailure()onTestSkipped()
You can use it to capture screenshots, logs, or custom reports.
🛠 Real-World TestNG Scenario Questions
16. How do you integrate TestNG with Maven?
Add dependency to pom.xml:
<dependency>
<groupId>org.testng</groupId>
<artifactId>testng</artifactId>
<version>7.8.0</version>
<scope>test</scope>
</dependency>
Then run using:
mvn test
17. What are some common exceptions in TestNG?
org.testng.SkipExceptionorg.testng.TestNGExceptionjava.lang.AssertionError(from failed assertions)
18. How do you handle multiple browsers in TestNG?
Use parameters or DataProviders to pass different browser names and launch accordingly via Selenium WebDriver.
19. What’s the difference between @BeforeMethod and @BeforeClass?
@BeforeMethod: Runs before each test method@BeforeClass: Runs once before all test methods in the class
20. How to generate HTML reports in TestNG?
By default, TestNG generates HTML and XML reports in the test-output directory. For advanced reporting, integrate with ExtentReports or Allure.
📋 Benefits of Using TestNG
Here are some compelling reasons to use TestNG in test automation:
- ✅ Powerful annotations for test lifecycle control
- ✅ Supports data-driven testing
- ✅ Easy integration with Selenium, Jenkins, Maven
- ✅ Parallel execution boosts efficiency
- ✅ Flexible test configuration with XML
- ✅ Rich HTML and XML reporting
- ✅ Easily manage test dependencies
- ✅ Supports soft assertions and custom listeners
❓ TestNG Interview FAQs
1. Is TestNG used only with Selenium?
No. TestNG is a general-purpose test framework for Java. However, it’s commonly used with Selenium for web UI testing.
2. Can I use TestNG with Cucumber?
Yes. You can integrate TestNG with Cucumber using runners, though Cucumber generally uses JUnit by default.
3. Which is better: JUnit or TestNG?
TestNG offers more flexibility, annotations, and features compared to JUnit, especially for Selenium automation.
🔊 Bonus Tip: Armenian Text to Speech Integration in Automation
For teams working on localization testing or voice interfaces, Armenian text-to-speech APIs can be integrated with TestNG for validating audio output in automated flows. Although this is a niche use case, it demonstrates the flexibility TestNG offers when extended with custom modules.
🎯 Final Thoughts
Mastering these TestNG interview questions will not only help you crack automation QA interviews but also strengthen your practical testing skills. Practice writing real-world test cases, explore edge scenarios, and get hands-on with testng.xml and reporting tools.
Want to level up further? Try integrating TestNG with CI tools like Jenkins or add cross-browser execution for bonus interview points!