Hey folks, In this article I'm going to cover the most important topic that is called TestNG Framework. In this article, we will cover the following topics
- Introduction to TestNG
- How to integrate TestNG with selenium?
- How to add TestNG into your project?
- How to use different annotations in TestNG?
1. Introduction to TestNG
TestNG is a unit testing framework for Java programming language and NG stand for Next Generation. It is also called the Java unit testing framework. It is a very famous framework used by the developers to test the code. When developers develop some code, they test their code at the class level with the help of the TestNG framework. It is also used by AUtomation Engineers to design the test cases. They can integrate it with selenium. It is a very powerful tool, it gives a lot of options and features to design your test cases. It can also generate HTML reports. The purpose of TestNG is to design the test cases in a systematic way. Here are some key features- Open source, free to use
- Available in the form of jar files
- Only applicable with Java
- Generate very good HTML reports
- Supports a lot of annotations
- Manage the sequence of test cases
- Manage priorities of test cases
- Manage test cases dependencies
- Manage test cases grouping
Whenever automation engineers design an automation framework they must use the TestNG because of its rich support in designing the test cases. So in another form, it is also called TDD framework. TDD means Test Driven Development. In TDD tests are written before writing the actual code. Developers write the tests first before implementing the actual code. Developers use TestNG for unit testing.
When you join a new company and you have a fresh project to start the automation framework from scratch, you can use TestNG to design the test cases in a systematic way.
2. TestNG Integration with Selenium
Now let's start from scratch, how to download and install TestNG in Eclipse. For this, you can visit the following article which will explain in detail how to install TestNG in Eclipse.How To Download And Install TestNG In Eclipse For Selenium WebDriver
3. Add TestNG into Your Project
Now let's see how to add the TestNG library into your project. The following steps are needed to add TestNG into your projectStep 1)
- Right-click on your project
- Click on Properties
Step 2)
- Click on Java Build Path
- Click on Add Library
Step 3)
- Select the library TestNG
- Click on Next button
Step 4)
- Click on Finish button
Step 5)
- Click on Apply and Close button
Step 6)
After creating a class let's try to write the selenium code with annotations. First, we explore what different annotations are available in TestNG.
TestNG provides different kinds of annotations. Every annotation is associated with one method. Annotations always start with @. In TestNG class, we simply write Java code with some other features provided by TestNG in the form of annotations. So when have you ever seen that some code is starting with "@" it means that is an annotation. In the TestNG framework, we will explore the following annotations.
In the above example, we have executed only one test case. Now let's see the scenario for more than one test case. If we add the following one more test case in the above example, the output will be a little bit different in terms of annotations sequence.
- Go to your project
- Check the TestNG folder
- As shown in the below image
4. Annotations in TestNG
Now let's try to explore how automation engineers design test cases with the TestNG framework. What are the different annotations which are used to design test cases? Let's create a separate project as I have created "TestNGBasics" for demonstration purposes.
Remember one thing while creating a class doesn't select the main method because in TestNG we don't' need the main method to run the class. TestNG automatically executes the class. We never work with the main method in the TestNG class.
After creating a class let's try to write the selenium code with annotations. First, we explore what different annotations are available in TestNG.
TestNG provides different kinds of annotations. Every annotation is associated with one method. Annotations always start with @. In TestNG class, we simply write Java code with some other features provided by TestNG in the form of annotations. So when have you ever seen that some code is starting with "@" it means that is an annotation. In the TestNG framework, we will explore the following annotations.
- @BeforeSuite
- @BeforeTest
- @BeforeClass
- @BeforeMethod
- @Test
- @AfterMethod
- @AfterCLass
- @AfterTest
- @AfterSuite
Given below is a demo example of TestNG annotations. This example is showing the use and sequence of annotations.
package com.test;
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 TestNGBasics {
@BeforeSuite
public void setUp() {
System.out.println("Set system properties for chrome");
}
@BeforeTest
public void launchBrowser() {
System.out.println("Launch chrome");
}
@BeforeClass
public void enterUrl() {
System.out.println("Enter URL");
}
@BeforeMethod
public void login() {
System.out.println("Login to app");
}
@Test
public void testTitle() {
System.out.println("Title test");
}
@AfterMethod
public void logOut() {
System.out.println("Log out from app");
}
@AfterClass
public void closeBrowser() {
System.out.println("Close Browser");
}
@AfterTest
public void generateReport() {
System.out.println("Delete Cookies");
}
}
The output is here
Output: Set system properties for chrome Launch chrome Enter URL Login to app Google title test Log out from the app Close Browser Delete Cookies
A TestNG class has three sections. The first section is the preconditions section, test case, and postconditions.
- Pre-Conditions
- Test Cases
- Post-Conditions
The annotations that start with @Before keyword come into the pre-conditions section. The second section contains the @Test annotation. The third section contains the annotations that start with @After keyword. The most important thing is the sequence of annotations. You should be familiar with the sequence of annotations. As you can see the sequence in the below diagram.
In the above example, we have executed only one test case. Now let's see the scenario for more than one test case. If we add the following one more test case in the above example, the output will be a little bit different in terms of annotations sequence.
public class TestNGBasics {
@BeforeSuite
public void setUp() {
System.out.println("Set system properties for chrome");
}
@BeforeTest
public void launchBrowser() {
System.out.println("Launch chrome");
}
@BeforeClass
public void enterUrl() {
System.out.println("Enter URL");
}
@BeforeMethod
public void login() {
System.out.println("Login to app");
}
// Test Case 1
@Test
public void testTitle() {
System.out.println("Title test");
}
Test Case 2
@Test
public void searchTest() {
System.out.println("Search test");
}
@AfterMethod
public void logOut() {
System.out.println("Log out from app");
}
@AfterClass
public void closeBrowser() {
System.out.println("Close Browser");
}
@AfterTest
public void generateReport() {
System.out.println("Delete Cookies");
}
}
The following is the output of the code
Output: Set system properties for chrome Launch chrome Enter URL // Test Case 2 Login to app Search test Log out from the app // Test Case 1 Login to app Title test Log out from the app Close Browser Delete Cookies
Remember one thing, the two annotations @BeforeMethod and @AfterMethod are executed for every test case. Suppose if you have n number of test cases, then these annotations will be executed n times. One more thing in the above output that is the test case 2 is executing first then test case 1. The reason is that TestNG executes the tests alphabetically. We can also set the priorities for test cases which we will cover in the next section.
Now let's try to write the selenium code with TestNG annotations. In the following example, you will also learn how to control the execution of test cases by using priorities. Suppose you have n number of the test case, you can set the priority of each test case. Based on these priorities execution will happen.
package com.test;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.testng.Assert;
import org.testng.annotations.AfterMethod;
import org.testng.annotations.BeforeMethod;
import org.testng.annotations.Test;
public class GoogleTest {
public String baseUrl = "http://google.com";
public WebDriver driver;
@BeforeMethod
public void launchBrowser() {
System.setProperty("webdriver.chrome.driver", "/home/khawer/Desktop/chromedriver");
driver = new ChromeDriver();
driver.get(baseUrl);
}
@Test(priority = 1)
public void googleTitle() {
String expectedTitle = "Google";
String actualTitle = driver.getTitle();
Assert.assertEquals(actualTitle, expectedTitle);
}
@Test(priority = 2)
public void logoTest() {
// Please write the logic here
}
@AfterMethod
public void close() {
driver.close();
}
}
Mostly the three annotations (@BeforeMethod, @Test, @AfterMethod) are used in TestNG. In t above example, we have used priority to control the execution of test cases. Priority 1 means this test case will be executed first then priority 2 and so on. I hope this article will make sense for you guys so far we have covered. In the next article, we will cover the @dataprovider annotation, HTML report some other stuff related to TestNG.
