Selenium Interview Questions with Answers

1) Which is the command used for displaying the values of a variable into the output console or log?

The command used for displaying the values of a variable into the output console or log–echo
If you want to display a constant string. The below mentioned command can be used
echo <constant string>
ex: echo “The sample message”
If you want to display the value of a variable it can be written like below
echo ${<variable name>>
ex: echo ${var1}

2) What are the capabilities of Selenium WebDriver or Google WebDriver or Selenium 2.0?

Capabilities of Selenium WebDriver or Google WebDriver or Selenium 2.0 are:
One should use WebDriver when requiring improved support for
1. Mult-browser testing including improved functionality for browsers not well-supported by Selenium-1.0.
2. Handling multiple frames, multiple browser windows, pop-ups, and alerts.
3. Page navigation.
4. Drag-and-drop.
5. AJAX-based UI elements.

3) Which are the browsers supported by Selenium RC?

Browsers supported by Selenium RC are:
1. *firefox
2. *mock
3. *firefoxproxy
4. *pifirefox
5. *chrome
6. *iexploreproxy
7. *iexplore
8. *firefox3
9. *safariproxy
10. *googlechrome
11. *konqueror
12. *firefox2
13. *safari
14. *piiexplore
15. *firefoxchrome
16. *opera
17. *iehta
18. *custom

4) What are the Operating Systems supported by Selenium?

Operating Systems supported by Selenium are:
Selenium IDE
Works in Firefox 2+ Start browser, run tests Run tests
Operating Systems Supported:
1. Windows,
2. OS X
3. Linux
4. Solaris
5. Others whichever supports Firefox 2+

Selenium Remote Control
Used for starting browser and run tests
Operating Systems Supported:
1. Windows,
2. OS X
3. Linux
4. Solaris
5. Others

Selenium Core
Used for running tests
Operating Systems Supported:
1. Windows,
2. OS X
3. Linux
4. Solaris
5. Others

5) What is the difference between an assert and a verify with Selenium commands?

Assert: Will fail and abort the current test execution.
Verify: Will fail and continue to run the test execution.

6) If a Selenium function requires a script argument, what would that argument look like in general terms?

StoreEval(script, variable) and storeExpression(expression, variableName).

7) If a Selenium function requires a pattern argument, what five prefixes might that argument have?

Five prefixes that Selenium pattern argument are:
glob, regexp, exact, regexpi.

8) Why Selenium RC is used?

We use Selenium RC for:
Selenium-IDE does not directly support:
1. Condition statements.
2. Iteration.
3. Logging and reporting of test results.
4. Error handling, particularly unexpected errors.
5. Database testing.
6. Test case grouping.
7. Re-execution of failed tests.
8. Test case dependency.
9. Capture screen shots on test failures.
The reason behind why Selenium-IDE does not support the above mentioned requirements is IDE supports only HTML language. Using HTML language we cannot achieve the above mentioned requirements. Because HTML does not support conditional, looping and external source connectives.
To overcome the above mentioned problems Selenium RC is used.

9) How many testing frameworks can QA Tester use in Selenium RC?

Testing frameworks aren’t required, but they can be helpful if QA Tester wants to automate test cases. Selenium RC supports Bromine, JUnit, NUnit, RSpec (Ruby), Test::Unit (Ruby), TestNG (Java), unittest (Python).

10) What is the architecture of Selenium RC?

The Selenium Server launches and kills browsers and acts as an HTTP proxy for browser requests.
Client libraries for various programming languages, each of which instructs the Selenium Server in how to test the AUT by passing it your test script’s Selenium commands.
The client libraries communicate with the Server passing each Selenium command for execution. Then the server passes the Selenium command to the browser using Selenium-Core JavaScript commands. The browser, using its JavaScript interpreter, executes the Selenium command, which effectively, runs the check you specified in your Selenese test script.

11) Does Selenium support mobile internet testing?
Selenium supports Opera and opera is used in most of the Smart phones. So whichever Smart phone supports opera, selenium can be used to test. So, one can use Selenium RC to run the tests on mobiles.

12) What are the basic annotations used to run TestNG tests in Selenium?

The basic annotations used to run TestNG tests in Selenium RC:
1. @BeforeClass: The annotated method with @BeforeClass will be run before the first test method in the current class is invoked.
2. @AfterClass: The annotated method with @AfterClass will be run after all the test methods in the current class have been run.
3. @BeforeMethod: The annotated method with @BeforeMethod will be run before each test method.
4. @AfterMethod: The annotated method with @AfterMethod will be run after each test method.
5. @Test: Marks a class or a method @Test with as part of the test.

13) What is the difference between Thread.Sleep() and Selenium.setSpeed()?
Selenium.setSpeed:
1. takes a single argument in string format
ex: selenium.setSpeed(“2000″) – will wait for 2 seconds
2. Runs each command in after setSpeed delay by the number of milliseconds mentioned in setSpeed.

Thread.sleep:
1. takes a single argument in integer format
ex: thread.sleep(2000) – will wait for 2 seconds
2. Waits for only once at the command given at sleep.

14)  How to configure Selenium RC with eclipse to run Junit Tests?

1) Download eclipse. click here to download the software
2) Open eclipse -> Workspace Launcher window will open
3) Create a workspace by giving meaningful name
3) Click on Workbench
4) Create a project of type java
5) Create a package under src folder of the package
6) Add Junit to the build path
7) Add selenium rc java client driver to the build path
8) Now drag and drop your test script (.which is exported from Selenium IDE) to the package created.

15) Actual end user simulation, Is the test conducted using this tool equivalent to an end user action?

Selenium performs actions in the background on the browser. It modifies the DOM structure of the HTML page in order to perform actions on the page. To be more precise it executes JavaScript on UI objects within the webpage to perform actions like click, type, select etc. This is the reason why you can execute tests with the browser minimized.

QTP claims to perform end user simulation, in other words executing QTP scripts are equivalent to a person performing those steps manually on the application.

16) Is it possible to use Selenium for multi-user Load Testing?
Yes, but it requires a LOT of hardware. We recommend you check out BrowserMob, which does load testing with real browsers and is powered by Selenium.