JUnit vs TestNG in Selenium

When working with Selenium for automated web testing in Java, choosing the right test framework is crucial. Two of the most popular testing frameworks are JUnit and TestNG. While both help in organizing and executing test cases, they have their strengths.

In this blog, we’ll compare JUnit and TestNG in the context of Selenium, highlight key differences, and show simple examples.

What Are JUnit and TestNG?

JUnit:

• A unit testing framework for Java, widely used for test-driven development.

• Simpler and ideal for smaller projects.

• Native support in most IDEs.

TestNG:

• Inspired by JUnit but more powerful and feature-rich.

• Great for complex test scenarios, such as parallel execution, dependency tests, and grouping.

Key Differences: JUnit vs TestNG

Simple Selenium Example: Login Test

Let’s assume we’re testing a login page using Selenium WebDriver.

Using JUnit:

import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;

public class LoginTestJUnit {
    WebDriver driver;

    @Before
    public void setUp() {
        driver = new ChromeDriver();
        driver.get("https://example.com/login");
    }

    @Test
    public void testLogin() {
        // add Selenium code to perform login
        System.out.println("Logging in with JUnit");
    }

    @After
    public void tearDown() {
        driver.quit();
    }
}

Using TestNG:

import org.testng.annotations.AfterClass;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.Test;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;

public class LoginTestTestNG {
    WebDriver driver;

    @BeforeClass
    public void setUp() {
        driver = new ChromeDriver();
        driver.get("https://example.com/login");
    }

    @Test
    public void testLogin() {
        // add Selenium code to perform login
        System.out.println("Logging in with TestNG");
    }

    @AfterClass
    public void tearDown() {
        driver.quit();
    }
}

Conclusion:

• Choose JUnit if your project is simple, or you’re working in an environment where it’s already integrated.

• Consider using TestNG if you require advanced features such as test dependencies, groups, or parallel test execution.

Both tools are capable and integrate well with Selenium — the choice largely depends on your project’s complexity and requirements.