Top 20 Java-based interview questions for automation testing:-

1. What is automation testing, and why is it important?
Answer: Automation testing is the use of software tools to execute test cases and compare actual outcomes with expected results. It is important because it saves time, improves test coverage, and increases efficiency.

2. What are the advantages of using Java for automation testing?
Answer: Java is platform-independent, has a rich set of libraries and frameworks, offers excellent support for web automation using Selenium, and has a large community for support and resources.

3. How do you handle exceptions in Java?
Answer: Exceptions are handled using try-catch blocks. Code that may throw an exception is placed in the try block, and the catch block handles the exception if it occurs.

4. Explain the difference between checked and unchecked exceptions.
Answer: Checked exceptions are checked at compile-time and must be declared in the method signature or handled using a try-catch block. Unchecked exceptions are not checked at compile-time and do not require explicit handling.

5. What is the difference between the “equals” and “==” operators in Java?
Answer: The “equals” operator compares the content of objects, whereas the “==” operator checks for reference equality, i.e., whether two objects refer to the same memory location.

6. How do you handle dynamic web elements in Selenium using Java?
Answer: Dynamic web elements can be handled using dynamic locators, such as XPath or CSS selectors, along with explicit waits to ensure the element is visible before interacting with it.

7. Explain the concept of inheritance in Java with an example.
Answer: Inheritance allows a class to inherit properties and methods from another class. For example, a “Car” class can inherit from a “Vehicle” class, inheriting its attributes and behaviours.

8. What is the difference between abstraction and encapsulation in Java?
Answer: Abstraction focuses on hiding implementation details and providing a simplified interface. Encapsulation is the bundling of data and methods together in a class, preventing direct access to the data.

9. How do you handle pop-up windows in Selenium using Java?
Answer: Pop-up windows can be handled using the “getWindowHandles” method to switch between windows, and the “Alert” class to handle JavaScript alerts.

10. What are the different types of waits in Selenium, and how do you implement them in Java?
Answer: There are three types of waits in Selenium: implicit, explicit, and fluent waits. Implicit waits are set globally, explicit waits are applied to specific elements, and fluent waits provide more flexibility using conditions.

11. How do you handle file uploads in Selenium using Java?
Answer: File uploads can be handled by sending the file path to the file input element using the “sendKeys” method in Selenium.

12. What is the difference between an implicit wait and an explicit wait in Selenium?
Answer: An implicit wait sets a global wait time for all elements, whereas an explicit wait is used for specific elements and allows more fine-grained control over the wait conditions.

13. How do you handle dropdown menus in Selenium using Java?
Answer: Dropdown menus can be handled using the “Select” class in Selenium. You can locate the dropdown element and use methods like “selectByVisibleText,” “selectByValue,” or “selectByIndex” to choose an option.

14. What is TestNG, and how is it beneficial for automation testing in Java?
Answer: TestNG is a testing framework for Java that provides advanced features like parallel test execution, test dependencies, data-driven testing, and test reporting. It enhances automation testing in terms of flexibility, organisation, and reporting capabilities.

15. How do you perform mouse hover actions in Selenium using Java?
Answer: Mouse hover actions can be performed using the “Actions” class in Selenium. You can use the “moveToElement” method to move the mouse pointer to a specific element and then perform actions like clicking or interacting with sub-elements.

16. Explain the concept of polymorphism in Java with an example.
Answer: Polymorphism allows objects of different classes to be treated as objects of a common superclass. For example, a superclass “Animal” can have subclasses like “Dog,” “Cat,” and “Lion.” You can use a common method, such as “makeSound,” and override it in each subclass to produce different sounds.

17. How do you handle multiple windows or tabs in Selenium using Java?
Answer: Multiple windows or tabs can be handled using the “getWindowHandles” method to retrieve the window handles, switching between windows using “switchTo().window,” and closing or navigating to a specific window using its handle.

18. What are the different types of frameworks used in automation testing with Java?
Answer: Some commonly used frameworks in automation testing with Java include TestNG, JUnit, Cucumber, Selenium WebDriver, and Apache POI for handling Excel files.

19. How do you capture screenshots in Selenium using Java?
Answer: Screenshots can be captured in Selenium using the “TakesScreenshot” interface. You can cast the WebDriver instance to TakesScreenshot and call the “getScreenshotAs” method to save the screenshot as a file.

20. How do you handle browser cookies in Selenium using Java?
Answer: Browser cookies can be handled using the “Cookies” interface in Selenium. You can use methods like “addCookie” to add a cookie, “getCookieNamed” to retrieve a specific cookie, or “deleteCookieNamed” to delete a cookie.

TYPES OF SOFTWARE TESTING:-

From the above picture you all will get a complete idea about types of Software Testing and how the Whole Process works.