TestNG – Test LifeCycle

TestNG lifecycle is controlled via lifecycle annotations. These lifecycle annotations are mainly the before and after annotations that are used to execute a certain set of code before and after the execution of actual tests.

These lifecycle methods are used to basically set up test infrastructure before the start of test execution and then to cleanup any of these things after the test execution ends.

1. TestNG Before and After Annotations

TestNG provides five different kinds of Before and After annotation options, each of which can be used depending upon the test requirements.

The following are different before and after lifecycle annotations provided by TestNG.

By default, all given above annotations run in the sequence discussed in the next section. Though, we can control the execution of these annotations using the attributes under specific requirements.

2. Lifecycle Sequence

Following is the sequence in which the lifecycle annotated methods will get executed.

1. @BeforeSuite
2. @BeforeTest
3. @BeforeClass
4. @BeforeMethod
5. @Test
6. @AfterMethod
7. @AfterClass
8. @AfterTest
9. @AfterSuite

3. Test Lifecycle Demo

Let’s try out an example containing all the preceding annotated methods and learn about when they are executed.

Create a new TestNG test having all before and after annotations. You can create this test with help of instructions given in this TestNG tutorial. Let’s see how you can select all before and after annotations.

After clicking on OK, you will get a test with all annotations. Add some print statements in all methods so that they can be tracked in which order they are executed.

import org.testng.annotations.AfterClass;
import org.testng.annotations.AfterMethod;
import org.testng.annotations.AfterSuite;
import org.testng.annotations.AfterTest;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.BeforeSuite;
import org.testng.annotations.BeforeTest;
import org.testng.annotations.Test;

public class MyFirstTest
{
	@Test
	public void testCase() {
	}

	@BeforeSuite
	public void beforeSuite() {
		System.out.println("Before Suite method");
	}

	@AfterSuite
	public void afterSuite() {
		System.out.println("After Suite method");
	}

	@BeforeTest
	public void beforeTest() {
		System.out.println("Before Test method");
	}

	@AfterTest
	public void afterTest() {
		System.out.println("After Test method");
	}

	@BeforeClass
	public void beforeClass() {
		System.out.println("Before Class method");
	}

	@AfterClass
	public void afterClass() {
		System.out.println("After Class method");
	}

	@BeforeMethod
	public void beforeMethod() {
		System.out.println("Before Method");
	}

	@AfterMethod
	public void afterMethod() {
		System.out.println("After Method");
	}
}

Now run the above test as the TestNG test and you will get the following output in the console.

[TestNG] Running:
  C:\Users\somepath\testng-customsuite.xml

Before Suite method
Before Test method
Before Class method
Before Method
After Method
After Class method
After Test method

PASSED: testCase

===============================================
    Default test
    Tests run: 1, Failures: 0, Skips: 0
===============================================

After Suite method

===============================================
Default suite
Total tests run: 1, Failures: 0, Skips: 0
===============================================

[TestNG] Time taken by org.testng.reporters.XMLReporter@177b3cd: 19 ms
[TestNG] Time taken by [FailedReporter passed=0 failed=0 skipped=0]: 0 ms
[TestNG] Time taken by org.testng.reporters.jq.Main@b8deef: 53 ms
[TestNG] Time taken by org.testng.reporters.JUnitReportReporter@10ab323: 13 ms
[TestNG] Time taken by org.testng.reporters.EmailableReporter2@5e176f: 11 ms
[TestNG] Time taken by org.testng.reporters.SuiteHTMLReporter@d1e89e: 184 ms

Congratulations, you have successfully created a test class with all kinds of before and after annotations and executed it.

4. Lifecycle Methods in Parent and Child Classes

The above example only contains annotations that are present in the same class. Let’s learn the execution flow when a class containing annotations is extended by another class having another set of before and after annotations.

TestNG guarantees that the “@Before” methods are executed in inheritance order (highest superclass first, then going down the inheritance chain), and the “@After” methods in reverse order (going up the inheritance chain).

Let’s create two new classes BaseClass and ChildClass. Then add similar before/after annotations on both of them. Here the main thing to notice is that ChildClass extends BaseClass. And Test is defined in ChildClass class.

4.1. BaseClass.java

import org.testng.annotations.AfterClass;
import org.testng.annotations.AfterMethod;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.BeforeMethod;

public class BaseClass {

	@BeforeMethod
	public void beforeMethod() {
		System.out.println("BaseClass's Before Test method");
	}

	@AfterMethod
	public void afterMethod() {
		System.out.println("BaseClass's After Test method");
	}

	@BeforeClass
	public void beforeClass() {
		System.out.println("BaseClass's Before Class method");
	}

	@AfterClass
	public void afterClass() {
		System.out.println("BaseClass's After Class method");
	}
}

4.2. ChildClass.java

import org.testng.annotations.AfterClass;
import org.testng.annotations.AfterMethod;
import org.testng.annotations.BeforeClass;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.Test;

public class ChildClass extends BaseClass {

	@BeforeMethod
	public void beforeChildMethod() {
		System.out.println("ChildClass's Before Test method");
	}

	@AfterMethod
	public void afterChildMethod() {
		System.out.println("ChildClass's After Test method");
	}

	@BeforeClass
	public void beforeChildClass() {
		System.out.println("ChildClass's Before Class method");
	}

	@AfterClass
	public void afterChildClass() {
		System.out.println("ChildClass's After Class method");
	}

	@Test
	public void testCase() {
		System.out.println("===== Executing actual test ======");
	}
}

4.3. Execution Sequence of Lifecycle Methods

Executing ChildClass test will generate the below output.

[TestNG] Running:
  C:\Users\somepath\testng-customsuite.xml

BaseClass's Before Class method
ChildClass's Before Class method
BaseClass's Before Test method
ChildClass's Before Test method
===== Executing actual test ======
ChildClass's After Test method
BaseClass's After Test method
ChildClass's After Class method
BaseClass's After Class method
PASSED: testCase

===============================================
    Default test
    Tests run: 1, Failures: 0, Skips: 0
===============================================

===============================================
Default suite
Total tests run: 1, Failures: 0, Skips: 0
===============================================

[TestNG] Time taken by org.testng.reporters.EmailableReporter2@1549f94: 13 ms
[TestNG] Time taken by [FailedReporter passed=0 failed=0 skipped=0]: 0 ms
[TestNG] Time taken by org.testng.reporters.XMLReporter@1bd7848: 16 ms
[TestNG] Time taken by org.testng.reporters.jq.Main@1342ba4: 52 ms
[TestNG] Time taken by org.testng.reporters.JUnitReportReporter@176e552: 12 ms
[TestNG] Time taken by org.testng.reporters.SuiteHTMLReporter@ff057f: 190 ms

As you can see from the report output:

• TestNG first executes the @Before annotated methods from the parent class and then from the child class.
• Then the test execution happens.
• The @After annotated methods are executed first in the child class and then in the parent class.

Happy Learning !!