TestNG Framework for Selenium

Introduction to TestNG

TestNG organises tests with annotations, groups, parallel runs and rich HTML reports. It is the runner behind most Java Selenium frameworks.

Annotations

@BeforeSuite @BeforeClass @BeforeMethod
@Test(priority = 1, groups = "smoke")
@AfterMethod @AfterClass @AfterSuite

Assertions

Assert.assertEquals(actual, expected); Assert.assertTrue(isLoggedIn). A failed assert fails the test and logs expected vs actual.

Groups, DataProvider, Parameters

@Test(groups = {"smoke", "regression"})
@DataProvider(name = "logins")
public Object[][] data() {
  return new Object[][] {
    {"user@test.com", "Pass@123", true},
    {"bad@test.com", "wrong", false} };
}
@Test(dataProvider = "logins")
public void login(String u, String p, boolean ok) { ... }

Reports and Parallel Testing

TestNG emits test-output HTML reports; plug ExtentReports for dashboards with screenshots. Run suites in parallel with testng.xml parallel=methods thread-count=4 to cut suite time.

Selenium + TestNG Project Layout

src/test/java/pages/LoginPage.java
src/test/java/tests/LoginTest.java
src/test/resources/testng.xml + testdata.csv

Key Points

• Annotations control order; groups control scope.
• DataProvider turns one test into fifty.
• Parallel runs plus CI equal fast feedback.