TestNG annotations (@Test, @BeforeMethod, @AfterMethod) in Selenium Java - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of the @Test annotation in TestNG?

The @Test annotation marks a method as a test case that TestNG will run. It tells TestNG this method contains test code to execute.

beginner

Explain the role of @BeforeMethod in TestNG.

@BeforeMethod runs before each @Test method. It is used to set up preconditions or initialize resources needed for the test.

beginner

What does the @AfterMethod annotation do in TestNG?

@AfterMethod runs after each @Test method. It is used to clean up or release resources after the test finishes.

intermediate

In what order do @BeforeMethod, @Test, and @AfterMethod run?

For each test method, TestNG runs @BeforeMethod first, then the @Test method, and finally @AfterMethod.

intermediate

Why is it useful to use @BeforeMethod and @AfterMethod instead of putting setup and cleanup code inside @Test methods?

Using @BeforeMethod and @AfterMethod avoids repeating setup and cleanup code in every test. It keeps tests clean and easier to maintain.

Which TestNG annotation is used to mark a method as a test case?

A @Test

B @BeforeMethod

C @AfterMethod

D @BeforeClass

@Test marks a method as a test case to be executed by TestNG.

When does a method annotated with @BeforeMethod run?

A After each @Test method

B Before all tests in the class

C Before each @Test method

D After all tests in the class

@BeforeMethod runs before each individual @Test method.

What is the main purpose of @AfterMethod?

A To skip tests

B To run tests

C To initialize test data

D To clean up after each test

@AfterMethod is used to clean up or release resources after each test.

If you have 3 @Test methods, how many times will @BeforeMethod run?

A 3

B 1

C 2

D Depends on the test

@BeforeMethod runs before each @Test method, so it runs 3 times for 3 tests.

Which annotation would you use to prepare test data before each test?

A @AfterMethod

B @BeforeMethod

C @Test

D @AfterClass

@BeforeMethod is used to set up or prepare data before each test.

Describe how @BeforeMethod, @Test, and @AfterMethod work together in a TestNG test class.

Think about what happens before, during, and after each test method.

Explain why using @BeforeMethod and @AfterMethod can improve test code quality compared to putting setup and cleanup inside @Test methods.

Consider how repeating code affects your tests.

Practice

1. What is the main purpose of the @BeforeMethod annotation in TestNG?

easy

A. To run a method before each test method to set up the test environment

B. To mark a method as a test case

C. To run a method after all test methods have finished

D. To skip a test method during execution

Solution

1. Step 1: Understand the role of @BeforeMethod

   This annotation is used to run a method before each test method to prepare or set up the environment.

2. Step 2: Differentiate from other annotations

   @Test marks test methods, @AfterMethod runs after each test, and skipping tests uses other annotations.

3. Final Answer:

   To run a method before each test method to set up the test environment -> Option A

4. Quick Check:

   @BeforeMethod = setup before each test [OK]

Hint: BeforeMethod always runs before each test method [OK]

Common Mistakes:

• Confusing @BeforeMethod with @BeforeClass
• Thinking @BeforeMethod runs only once
• Mixing @BeforeMethod with @AfterMethod

2. Which of the following is the correct syntax to mark a method as a test case in TestNG?

easy

A. @BeforeMethod void testMethod() {}

B. @Test void testMethod() {}

C. @AfterMethod void testMethod() {}

D. test void testMethod() {}

Solution

1. Step 1: Identify the annotation for test methods

   @Test is the correct annotation to mark a method as a test case in TestNG.

2. Step 2: Check syntax correctness

   The method signature with @Test void testMethod() {} is valid Java and TestNG syntax.

3. Final Answer:

   @Test void testMethod() {} -> Option B

4. Quick Check:

   @Test marks test methods [OK]

Hint: Use @Test to mark test methods in TestNG [OK]

Common Mistakes:

• Using @BeforeMethod or @AfterMethod instead of @Test
• Missing parentheses in method declaration
• Writing 'test' instead of '@Test'

3. Consider the following TestNG class:

public class SampleTest {
  @BeforeMethod
  public void setup() {
    System.out.println("Setup");
  }

  @Test
  public void test1() {
    System.out.println("Test1");
  }

  @Test
  public void test2() {
    System.out.println("Test2");
  }

  @AfterMethod
  public void cleanup() {
    System.out.println("Cleanup");
  }
}

What will be the order of printed lines when this test class runs?

medium

A. Test1
Test2
Setup
Cleanup

B. Setup
Cleanup
Test1
Setup
Cleanup
Test2

C. Setup
Test1
Test2
Cleanup

D. Setup
Test1
Cleanup
Setup
Test2
Cleanup

Solution

1. Step 1: Understand TestNG execution flow

   For each @Test method, @BeforeMethod runs before it and @AfterMethod runs after it.

2. Step 2: Trace the print statements

   First test: Setup -> Test1 -> Cleanup. Second test: Setup -> Test2 -> Cleanup.

3. Final Answer:

   Setup Test1 Cleanup Setup Test2 Cleanup -> Option D

4. Quick Check:

   BeforeMethod and AfterMethod wrap each test [OK]

Hint: BeforeMethod and AfterMethod run around each test [OK]

Common Mistakes:

• Assuming BeforeMethod runs once before all tests
• Assuming AfterMethod runs once after all tests
• Mixing order of print statements

4. Identify the error in the following TestNG code snippet:

public class TestExample {
  @BeforeMethod
  public void setup() {
    System.out.println("Setup");
  }

  @Test
  public void testMethod() {
    System.out.println("Test");
  }

  @AfterMethod
  public void cleanup() {
    System.out.println("Cleanup")
  }
}

medium

A. Missing semicolon after System.out.println("Cleanup")

B. Incorrect annotation @AfterMethod should be @AfterTest

C. setup() method should be static

D. testMethod() must return boolean

Solution

1. Step 1: Check syntax in cleanup() method

   The line System.out.println("Cleanup") is missing a semicolon at the end.

2. Step 2: Verify other parts

   Annotations are correct, methods do not need to be static, and test methods can be void.

3. Final Answer:

   Missing semicolon after System.out.println("Cleanup") -> Option A

4. Quick Check:

   Java statements must end with semicolon [OK]

Hint: Check for missing semicolons in Java code [OK]

Common Mistakes:

• Confusing @AfterMethod with @AfterTest
• Thinking test methods must return boolean
• Assuming setup() must be static

5. You want to run a setup method once before all tests in a TestNG class and a cleanup method after each test method. Which annotations should you use for these methods?

hard

A. @BeforeMethod for setup, @AfterMethod for cleanup

B. @BeforeMethod for setup, @AfterClass for cleanup

C. @BeforeClass for setup, @AfterMethod for cleanup

D. @BeforeTest for setup, @AfterTest for cleanup

Solution

1. Step 1: Identify annotation to run once before all tests

   @BeforeClass runs once before any test methods in the class.

2. Step 2: Identify annotation to run after each test method

   @AfterMethod runs after each test method to clean up.

3. Final Answer:

   @BeforeClass for setup, @AfterMethod for cleanup -> Option C

4. Quick Check:

   BeforeClass = once before all, AfterMethod = after each test [OK]

Hint: Use BeforeClass once, AfterMethod after each test [OK]

Common Mistakes:

• Using BeforeMethod for setup once only
• Using AfterClass for cleanup after each test
• Confusing BeforeTest with BeforeClass