Automation Testing Insider: Selenium Questions Part3: Theoretical Questions on Selenium

1.What do we mean by Selenium 1, Selenium 2 and Selenium 3?

Answer: Earlier Selenium 1 used to be the major project of Selenium.

Selenium 1 = Selenium IDE + Selenium RC + Selenium Grid

Later Selenium Team has decided to merge both Selenium WebDriver and Selenium RC to form a more powerful Selenium tool.

They both got merged to form “Selenium 2”

“Selenium WebDriver” was the core of “Selenium 2” and “Selenium RC” used to run in maintenance mode.

Hence Selenium 2 = Selenium IDE + Selenium WebDriver 2.x + Selenium Grid.

“Selenium 2” released on July 8, 2011.

Selenium team has decided to completely remove the dependency for Selenium RC.

After 5 years, “Selenium 3" was released on October 13, 2016 with a major change, which is the original Selenium Core implementation and replacing it with one backed by WebDriver and lot more improvements.

Hence Selenium 3 = Selenium IDE + Selenium WebDriver 3.x + Selenium Grid.

After 3 years from it’s a major release, now Selenium has put out its first alpha version of Selenium 4 on Apr 24, 2019. Still, there is no official announcement about the release date of Selenium 4, but we are expecting it around October 2019. Till that there can be several alpha or beta versions released time to time with stabilization.

2. When should I use Selenium Grid?

Answer: Selenium Grid is a part of the Selenium Suite that specializes in running multiple tests across different browsers, operating systems, and machines in parallel.

You should use Selenium Grid when you want to do either one or both of following:

1.For Parellel Testing - Run your tests against different browsers, operating systems, and machines all at the same time. This will ensure that the application you are Testing is fully compatible with a wide range of browser-O.S combinations.

2. Save time in the execution of your test suites. If you set up Selenium Grid to run, say, 4 tests at a time, then you would be able to finish the whole suite around 4 times faster.

3. What are the different types of drivers available in WebDriver?

Answer: Drivers are required for different types of browsers.

Here is the list of different types of drivers available in Selenium WebDriver.

FirefoxDriver
InternetExplorerDriver
ChromeDriver
SafariDriver
OperaDriver
AndroidDriver
IPhoneDriver
HTMLUnitDriver

4. Is WebDriver a class or interface?

Answer: WebDriver is an Interface,and we are defining a reference variable(driver) whose type is an interface. Now any object we assign to it must be an instance of a class(FireFoxDriver) that implements the interface. Whenever we use Selenium for automation ,the first line of our Program starts with the code to invoke Fire Fox Driver

WebDriver driver = new FireFoxDriver();

5. What is the super interface of WebDriver ?

Answer: SearchContext is the super most interface in selenium, which is extended by another interface called WebDriver. All the abstract methods of SearchContext and WebDriver interfaces are implemented in RemoteWebDriver class.

6. Is FirefoxDriver a class or interface?

Answer: FirefoxDriver is a class that has been written specifically for the Firefox browser. It has methods that are implemented and it can be instantiated. It can perform all functions (or methods) on the Firefox browser as defined in the interface WebDriver.

7. Why do we create a reference variable ‘driver’ of type WebDriver and what is the purpose of its creation?

Answer: Having a reference variable of type WebDriver allows us to assign the driver object to different browser specific drivers. Thus allowing multi-browser testing by assigning the driver object to any of the desired browser.

8. Explain the line of code WebDriver driver = new FirefoxDriver();?

Answer: WebDriver driver = new FirefoxDriver();

We can create Object of a class FirefoxDriver by taking reference of an interface (WebDriver). In this case, we can call implemented methods of WebDriver interface.

As per the above statement, we are creating an instance of the WebDriver interface and casting it to FirefoxDriver Class. All other Browser Drivers like ChromeDriver, InternetExplorerDriver, PhantomJSDriver, SafariDriver etc implemented the WebDriver interface (actually the RemoteWebDriver class implements WebDriver Interface and the Browser Drivers extends RemoteWebDriver). Based on this statement, you can assign Firefox driver and run the script in Firefox browser (any browser depends on your choice).

9. What are the different types of navigation commands in WebDriver?

Answer: Browser Navigation Commands:

WebDriver provides some basic Browser Navigation Commands that allows the browser to move backwards or forwards in the browser's history.

1. Navigate To:

Method - String to(String arg0)

In WebDriver, this method loads a new web page in the existing browser window. It accepts String as parameter and returns void. The respective command to load/navigate a new web page can be written as:

Example:

driver.navigate().to("www.automationtestinginsider.com");

2. Backward:

Method - void back()

This method enables the web browser to click on the back button in the existing browser window. It neither accepts anything nor returns anything. The respective command that takes you back by one page on the browser's history can be written as:

Example:

driver.navigate().back();

3. Forward:

Method - void forward()

This method enables the web browser to click on the forward button in the existing browser window. It neither accepts anything nor returns anything. The respective command that takes you forward by one page on the browser's history can be written as:

Example:

driver.navigate().forward();

4. Refresh:

Method - void refresh()

In WebDriver, this method refresh/reloads the current web page in the existing browser window. It neither accepts anything nor returns anything. The respective command that takes you back by one page on the browser's history can be written as:

Example:

driver.navigate().refresh();

Complete article: https://www.automationtestinginsider.com/2019/10/webdriver-commands.html

10. What are the different types of waits available in WebDriver?

Answer: Please refer complete article here

https://www.automationtestinginsider.com/2020/02/waits-in-selenium-webdriver.html

11. What is the difference between driver.close() and driver.quit() commands?

Answer: driver. quit() is used to exit the browser, end the session, tabs, pop-ups etc. But the when you driver. close(), only the window that has focus is closed.

12. Can Selenium Automate Desktop Applications?

Answer: Selenium does not have the capability to automate the desktop applications.It cannot recognize the objects in a desktop application. Selenium drives the testing using the driver object that identifies the elements on screen using id, cssselector, xpath etc. which are not present in a desktop app.

13. What is the difference between Assert and Verify commands?

Answer: In case of the “Assert” command, as soon as the validation fails the execution of that particular test method is stopped and the test method is marked as failed. Whereas, in case of “Verify”, the test method continues execution even after the failure of an assertion statement.

Assert

We use Assert when we have to validate critical functionality, failing of which makes the execution of further statements irrelevant. Hence, the test method is aborted as soon as failure occurs.

@Test

public void assertionTest(){

   //Assertion Passing

   Assert.assertTrue(1+2 == 3);

   System.out.println("Passing 1");

   //Assertion failing

   Assert.fail("Failing second assertion");

   System.out.println("Failing 2");

}

Output-

Passing 1

FAILED: assertionTest

java.lang.AssertionError: Failing second assertion

Verify

At times, we might require the test method to continue execution even after the failure of the assertion statements. In TestNG, Verify is implemented using SoftAssert class.

In case of SoftAssert, all the statements in the test method are executed (including multiple assertions).

@Test

public void softAssertionTest(){

   //Creating softAssert object

   SoftAssert softAssert = new SoftAssert();

   //Assertion failing

   softAssert.fail("Failing first assertion");

   System.out.println("Failing 1");

  
   //Assertion failing

   softAssert.fail("Failing second assertion");

   System.out.println("Failing 2");

   //Collates the assertion results and marks test as pass or fail

   softAssert.assertAll();

}

Output-

Failing 1

Failing 2

FAILED: softAssertionTest

java.lang.AssertionError: The following asserts failed:

    Failing first assertion,

    Failing second assertion

Here, we can see that even though both the test methods are bound to fail, still the test continues to execute.

14. Can Captcha be automated using Selenium?

Answer: No. CAPTCHA can be automated if you are able to decode the image using OCR (Optical Character Recognition). For that, one will need to write complex algorithm to sort out the image pattern and has to be an expert in image pattern mapping as well. But images with the passage of time have become progressively more unreadable, therefore reducing the very chances of CAPTCHA automation.

15. What is Object Repository and how can we create an Object Repository in Selenium?

Answer: An object repository is a common storage location for all objects. In Selenium WebDriver context, objects would typically be the locators used to uniquely identify web elements.

The major advantage of using object repository is the segregation of objects from test cases. If the locator value of one webelement changes, only the object repository needs to be changed rather than making changes in all test cases in which the locator has been used. Maintaining an object repository increases the modularity of framework implementation.

An object repository is a common storage location for all objects. In Selenium WebDriver context, objects would typically be the locators used to uniquely identify web elements.

A property file stores information in a Key-Value pair. Key value pair is represented by two string values separated by the equal to sign.

There are two ways to create object repository in Selenium:

1. any companies also use Page Object Model to store all locators which also make the test in a readable format. Depends on your current framework style you can adopt any of these. Personally, I use Page Object Model using PageFactory which make my test more readable and in terms of performance as well.

2. Using Properties file, Ex: ObjectRepo.peroperties

16. What are the types of WebDriver API’s that are supported/available in Selenium?

Answer: Please refer answer of question#108

17. Which WebDriver implementation claims to be the fastest?

Answer: The fastest implementation of WebDriver is the HTMLUnitDriver. It is because the HTMLUnitDriver does not execute tests in the browser and also called as a Headless browser.

18. What is the difference between Soft Assert and Hard Assert in Selenium?

Answer: Please refer answer of question#13

19. What are the verification points available in Selenium?

Answer: Here some examples of verification

To check if element is enabled or not

driver.findElement(By.id("<ID>")).isEnabled()

To check if element is displayed or not

driver.findElement(By.id("<ID>")).isDisplayed()

To check if element is selected or not

driver.findElement(By.id("<ID>")).isSelected()

To check if element is currently active or not on the page

driver.findElement(By.id("<ID>")).equals(driver.switchTo().activeElement());

20. Is Selenium Server needed to run Selenium WebDriver scripts?

Answer: In case of Selenium WebDriver, it does not require to start Selenium Server for executing test scripts. Selenium WebDriver makes the calls between browser & automation script. Selenium WebDriver has native support for each browser to supports Test Automation; on the same machine (both Selenium WebDriver Automation tests & browsers are on same machine.

21. What are the different ways for refreshing the page using Selenium WebDriver?

Answer: 1) Refresh command: The most commonly used and simple command for refreshing a webpage.