TestNG and JUnit Integration

Integrate Selenium with TestNG and JUnit test frameworks for structured, maintainable Java tests.

Selenium 3 & 4 Stable

TestNG and JUnit are the two most popular testing frameworks for Java. Both integrate seamlessly with Selenium to provide test organization, assertions, and reporting.

TestNG Setup

Maven Dependencies

<dependencies>
    <dependency>
        <groupId>org.seleniumhq.selenium</groupId>
        <artifactId>selenium-java</artifactId>
        <version>4.18.1</version>
    </dependency>
    <dependency>
        <groupId>org.testng</groupId>
        <artifactId>testng</artifactId>
        <version>7.9.0</version>
        <scope>test</scope>
    </dependency>
</dependencies>

Basic TestNG Test

import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.By;
import org.testng.annotations.*;
import org.testng.Assert;

public class LoginTest {
    private WebDriver driver;

    @BeforeClass
    public void setupClass() {
        // Runs once before all tests in this class
        System.out.println("Setting up test class");
    }

    @BeforeMethod
    public void setup() {
        // Runs before each test method
        driver = new ChromeDriver();
        driver.manage().window().maximize();
    }

    @Test(priority = 1)
    public void testValidLogin() {
        driver.get("https://example.com/login");
        driver.findElement(By.id("username")).sendKeys("validuser");
        driver.findElement(By.id("password")).sendKeys("validpass");
        driver.findElement(By.id("login")).click();

        Assert.assertTrue(driver.getCurrentUrl().contains("/dashboard"),
            "Should redirect to dashboard");
    }

    @Test(priority = 2)
    public void testInvalidLogin() {
        driver.get("https://example.com/login");
        driver.findElement(By.id("username")).sendKeys("invalid");
        driver.findElement(By.id("password")).sendKeys("wrong");
        driver.findElement(By.id("login")).click();

        String error = driver.findElement(By.className("error")).getText();
        Assert.assertEquals(error, "Invalid credentials");
    }

    @AfterMethod
    public void teardown() {
        // Runs after each test method
        if (driver != null) {
            driver.quit();
        }
    }

    @AfterClass
    public void teardownClass() {
        // Runs once after all tests in this class
        System.out.println("Tests completed");
    }
}

TestNG Annotations Reference

Annotation	Description
`@BeforeSuite`	Before all tests in suite
`@BeforeClass`	Before first test in class
`@BeforeMethod`	Before each test method
`@Test`	Marks test method
`@AfterMethod`	After each test method
`@AfterClass`	After last test in class
`@AfterSuite`	After all tests in suite

TestNG Data Providers

import org.testng.annotations.DataProvider;

public class DataDrivenTest {
    private WebDriver driver;

    @BeforeMethod
    public void setup() {
        driver = new ChromeDriver();
    }

    @DataProvider(name = "loginData")
    public Object[][] loginDataProvider() {
        return new Object[][] {
            {"user1", "pass1", true},
            {"user2", "pass2", true},
            {"invalid", "wrong", false}
        };
    }

    @Test(dataProvider = "loginData")
    public void testLogin(String username, String password, boolean shouldPass) {
        driver.get("https://example.com/login");
        driver.findElement(By.id("username")).sendKeys(username);
        driver.findElement(By.id("password")).sendKeys(password);
        driver.findElement(By.id("login")).click();

        if (shouldPass) {
            Assert.assertTrue(driver.getCurrentUrl().contains("/dashboard"));
        } else {
            Assert.assertTrue(driver.findElement(By.className("error")).isDisplayed());
        }
    }

    @AfterMethod
    public void teardown() {
        driver.quit();
    }
}

TestNG XML Suite

<!DOCTYPE suite SYSTEM "https://testng.org/testng-1.0.dtd">
<suite name="Regression Suite" parallel="methods" thread-count="3">
    <test name="Login Tests">
        <classes>
            <class name="tests.LoginTest"/>
            <class name="tests.RegistrationTest"/>
        </classes>
    </test>

    <test name="Search Tests">
        <classes>
            <class name="tests.SearchTest"/>
        </classes>
    </test>
</suite>

JUnit 5 Setup

Maven Dependencies

<dependencies>
    <dependency>
        <groupId>org.seleniumhq.selenium</groupId>
        <artifactId>selenium-java</artifactId>
        <version>4.18.1</version>
    </dependency>
    <dependency>
        <groupId>org.junit.jupiter</groupId>
        <artifactId>junit-jupiter</artifactId>
        <version>5.10.2</version>
        <scope>test</scope>
    </dependency>
</dependencies>

Basic JUnit 5 Test

import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.By;
import org.junit.jupiter.api.*;
import static org.junit.jupiter.api.Assertions.*;

class LoginTest {
    private WebDriver driver;

    @BeforeAll
    static void setupAll() {
        // Runs once before all tests
        System.out.println("Setting up test class");
    }

    @BeforeEach
    void setup() {
        // Runs before each test
        driver = new ChromeDriver();
        driver.manage().window().maximize();
    }

    @Test
    @DisplayName("Valid user can login successfully")
    void testValidLogin() {
        driver.get("https://example.com/login");
        driver.findElement(By.id("username")).sendKeys("validuser");
        driver.findElement(By.id("password")).sendKeys("validpass");
        driver.findElement(By.id("login")).click();

        assertTrue(driver.getCurrentUrl().contains("/dashboard"),
            "Should redirect to dashboard");
    }

    @Test
    @DisplayName("Invalid credentials show error")
    void testInvalidLogin() {
        driver.get("https://example.com/login");
        driver.findElement(By.id("username")).sendKeys("invalid");
        driver.findElement(By.id("password")).sendKeys("wrong");
        driver.findElement(By.id("login")).click();

        String error = driver.findElement(By.className("error")).getText();
        assertEquals("Invalid credentials", error);
    }

    @AfterEach
    void teardown() {
        if (driver != null) {
            driver.quit();
        }
    }

    @AfterAll
    static void teardownAll() {
        System.out.println("Tests completed");
    }
}

JUnit 5 Annotations Reference

Annotation	Description
`@BeforeAll`	Before all tests (static)
`@BeforeEach`	Before each test
`@Test`	Marks test method
`@AfterEach`	After each test
`@AfterAll`	After all tests (static)
`@DisplayName`	Custom test name
`@Disabled`	Skip test

JUnit 5 Parameterized Tests

import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.*;

class ParameterizedLoginTest {
    private WebDriver driver;

    @BeforeEach
    void setup() {
        driver = new ChromeDriver();
    }

    @ParameterizedTest
    @CsvSource({
        "user1, pass1, true",
        "user2, pass2, true",
        "invalid, wrong, false"
    })
    void testLogin(String username, String password, boolean shouldPass) {
        driver.get("https://example.com/login");
        driver.findElement(By.id("username")).sendKeys(username);
        driver.findElement(By.id("password")).sendKeys(password);
        driver.findElement(By.id("login")).click();

        if (shouldPass) {
            assertTrue(driver.getCurrentUrl().contains("/dashboard"));
        } else {
            assertTrue(driver.findElement(By.className("error")).isDisplayed());
        }
    }

    @ParameterizedTest
    @ValueSource(strings = {"chrome", "firefox", "edge"})
    void testBrowsers(String browser) {
        // Test across browsers
    }

    @AfterEach
    void teardown() {
        driver.quit();
    }
}

Base Test Class Pattern

// For TestNG
public class BaseTest {
    protected WebDriver driver;
    protected WebDriverWait wait;

    @BeforeMethod
    public void setup() {
        driver = DriverFactory.getDriver();
        wait = new WebDriverWait(driver, Duration.ofSeconds(10));
        driver.manage().window().maximize();
    }

    @AfterMethod
    public void teardown(ITestResult result) {
        if (result.getStatus() == ITestResult.FAILURE) {
            takeScreenshot(result.getName());
        }
        DriverFactory.quitDriver();
    }

    protected void takeScreenshot(String name) {
        // Screenshot logic
    }
}

// Tests extend BaseTest
public class LoginTest extends BaseTest {
    @Test
    public void testLogin() {
        driver.get("https://example.com");
        // Test logic using inherited driver
    }
}

TestNG vs JUnit 5

Feature	TestNG	JUnit 5
Parallel execution	Built-in XML config	Jupiter parallel config
Data providers	`@DataProvider`	`@ParameterizedTest`
Test groups	`@Test(groups="")`	`@Tag`
Dependencies	`dependsOnMethods`	`@Order`
Suite files	XML-based	Programmatic
Reporting	Built-in HTML	Requires plugins

Next Steps

Page Object Model - Structure your tests
Parallel Execution - Run tests concurrently
Data-Driven Testing - External test data
pytest Integration - Python framework comparison