TestNG Testing Skill

When to Use

Use this skill when you need generates TestNG tests in Java with groups, data providers, parallel execution, XML suite configuration, and listeners. Use when user mentions "TestNG", "@DataProvider", "testng.xml", "groups". Triggers on: "TestNG", "@DataProvider", "testng.xml", "TestNG suite", "parallel tests Java".

Core Patterns

Basic Test with Groups

import org.testng.annotations.*;
import org.testng.Assert;

public class LoginTest {
    @BeforeMethod
    public void setUp() { /* setup */ }

    @Test(groups = "smoke")
    public void testLoginSuccess() {
        Assert.assertTrue(loginService.login("user@test.com", "password123"));
    }

    @Test(groups = "regression", dependsOnMethods = "testLoginSuccess")
    public void testAccessDashboard() {
        Assert.assertNotNull(dashboard.getContent());
    }

    @Test(expectedExceptions = AuthenticationException.class)
    public void testLoginInvalidPassword() {
        loginService.login("user@test.com", "wrong");
    }

    @AfterMethod
    public void tearDown() { /* cleanup */ }
}

Data Providers

@DataProvider(name = "loginData")
public Object[][] loginData() {
    return new Object[][] {
        {"admin@test.com", "admin123", true},
        {"user@test.com", "password", true},
        {"invalid@test.com", "wrong", false},
    };
}

@Test(dataProvider = "loginData")
public void testLogin(String email, String password, boolean expected) {
    Assert.assertEquals(loginService.login(email, password), expected);
}

TestNG XML Suite

<!DOCTYPE suite SYSTEM "https://testng.org/testng-1.0.dtd">
<suite name="Regression" parallel="tests" thread-count="5">
  <test name="Smoke">
    <groups><run><include name="smoke"/></run></groups>
    <classes><class name="tests.LoginTest"/></classes>
  </test>
  <test name="Full">
    <groups><run><include name="regression"/><exclude name="flaky"/></run></groups>
    <packages><package name="tests.*"/></packages>
  </test>
</suite>

Parallel Execution

<suite parallel="methods" thread-count="5">   <!-- Method level -->
<suite parallel="classes" thread-count="5">    <!-- Class level -->
<suite parallel="tests" thread-count="5">      <!-- Test level -->

Soft Assertions

SoftAssert soft = new SoftAssert();
soft.assertEquals(user.getName(), "Alice");
soft.assertEquals(user.getAge(), 25);
soft.assertTrue(user.isActive());
soft.assertAll();  // Reports all failures at once

Listeners

public class TestListener implements ITestListener {
    @Override public void onTestFailure(ITestResult result) {
        System.out.println("Failed: " + result.getName());
        // Take screenshot, log, etc.
    }
}

@Listeners(TestListener.class)
public class LoginTest { /* ... */ }

Lifecycle Annotations

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

Anti-Patterns

Quick Reference

Deep Patterns → reference/playbook.md

Limitations

• Use this skill only when the task clearly matches its upstream source and local project context.
• Verify commands, generated code, dependencies, credentials, and external service behavior before applying changes.
• Do not treat examples as a substitute for environment-specific tests, security review, or user approval for destructive or costly actions.