TestNG vs JUnit

 

Below is the detailed comparison between TestNG and JUnit, followed by Java code examples to demonstrate the key differences:

TestNG vs JUnit – Key Differences

Feature	TestNG	JUnit (JUnit 4/5)
Framework	Open Source Java-based Testing framework	Open Source Testing framework
Annotations	@BeforeSuite, @AfterClass, @Test, etc.	@Before, @After, @Test, etc.
Dependency Testing	Supports method dependencies using dependsOnMethods	Not directly supported
Supported Testing	Unit Testing, Functional Testing, Integration Testing, end-to-end Testing, etc.	Unit Testing
Suite Execution	Allows XML-based suite execution	Uses test runners like @RunWith
Parallel Execution	Built-in support with XML config	Requires third-party tools
Order of Tests	Supports ordering of test methods via a priority attribute	Does not support
Groups	Supports grouping of test	No built-in group support
Reports	Rich HTML/XML reports	Basic reports unless extended
Popular In	Selenium & Test Automation	General Unit Testing

TestNG Example

import org.testng.annotations.*;

public class TestNGExample {

    @BeforeClass
    public void setup() {
        System.out.println("TestNG: Setup before class");
    }

    @Test(priority = 1)
    public void loginTest() {
        System.out.println("TestNG: Executing login test");
    }

    @Test(priority = 2, dependsOnMethods = {"loginTest"})
    public void dashboardTest() {
        System.out.println("TestNG: Executing dashboard test");
    }

    @AfterClass
    public void teardown() {
        System.out.println("TestNG: Teardown after class");
    }
}

JUnit Example (JUnit 4)

import org.junit.*;

public class JUnitExample {

    @BeforeClass
    public static void setup() {
        System.out.println("JUnit: Setup before class");
    }

    @Test
    public void loginTest() {
        System.out.println("JUnit: Executing login test");
    }

    @Test
    public void dashboardTest() {
        System.out.println("JUnit: Executing dashboard test");
    }

    @AfterClass
    public static void teardown() {
        System.out.println("JUnit: Teardown after class");
    }
}

Note: JUnit doesn't support method dependency like TestNG.

Important Points:

• Use TestNG for: complex test suites, method dependencies, grouping, parameterization, and Selenium testing.

• Use JUnit for: standard unit testing, integration with Java frameworks, and simplicity.