Top Java Selenium Interview Questions & Answers

1. What is Java?

Java is a high-level, object-oriented, platform-independent programming language used for developing web, desktop, mobile, and automation applications.

2. What are the features of Java?

Platform independent
Object-oriented
Secure
Robust
Multithreaded
Portable

3. What are variables in Java?

Variables are containers used to store data values.

Example:

int age = 25;

4. What are data types in Java?

Two types:

Primitive → int, char, boolean
Non-primitive → String, Array, Class

5. What is the difference between primitive and non-primitive data types?

Primitive	Non-Primitive
Stores value	Stores reference
Fixed size	Dynamic size

6. What is type casting in Java?

Converting one datatype into another datatype.

Example:

double d = 10.5;
int i = (int)d;

7. What are operators in Java?

Operators perform operations on variables.

Examples:

Arithmetic (+)
Logical (&&)
Relational (>)

8. What is the difference between == and .equals()?

==	.equals()
Compares memory reference	Compares values

9. What are OOPs concepts in Java?

Encapsulation
Inheritance
Polymorphism
Abstraction

10. What is encapsulation?

Encapsulation means wrapping data and methods together in a single class and restricting direct access using private variables.

11. What is inheritance?

Inheritance allows one class to acquire properties and methods of another class using extends keyword.

12. What is polymorphism?

Polymorphism means one method can perform different actions based on the object.
Types:

Overloading
Overriding

13. What is abstraction?

Abstraction means hiding implementation details and showing only required functionality.

14. What is the difference between abstraction and encapsulation?

Abstraction	Encapsulation
Hides implementation	Hides data

15. What is method overloading?

Method overloading means creating multiple methods with same name but different parameters.

16. What is method overriding?

Method overriding means redefining parent class method in child class with same signature.

17. What is the difference between overloading and overriding?

Overloading	Overriding
Same class	Parent-child class
Different parameters	Same parameters
Compile-time polymorphism	Runtime polymorphism

18. What is an interface in Java?

An interface is a blueprint containing abstract methods that must be implemented by classes.

19. What is an abstract class?

An abstract class is a class declared using abstract keyword. It can contain abstract and non-abstract methods

20. What is the difference between interface and abstract class?

Interface	Abstract Class
Supports multiple inheritance	Partial abstraction
Mostly abstract methods	Can contain concrete methods

21. What is constructor in Java?

Constructor initializes object.

22. What is constructor overloading?

A constructor is a special method used to initialize objects.

23. What is constructor overloading?

Creating multiple constructors with different parameters is called constructor overloading

23. What is the difference between a constructor and a method?

Constructor	Method
Initializes object	Performs operations
Same name as class	Any valid name

24. What is this keyword?

Refers to current class object.

25. What is super keyword?

super refers to parent class object or constructor.

26. What is static keyword in Java?

static belongs to class instead of object.

27. What is final keyword in Java?

Used to:

Prevent inheritance
Prevent overriding
Declare constants

28. Can we override static or final methods?

No, static and final methods cannot be overridden.

29. What is String in Java?

String is a sequence of characters used to store text.

30. What is the difference between String, StringBuffer, and StringBuilder?

String	StringBuffer	StringBuilder
Immutable	Mutable	Mutable
Slow	Thread-safe	Faster

31. Why is String immutable in Java?

For security, thread safety, and performance.

32. What is string pooling?

Java stores string literals in common memory called String Pool.

33. What is the difference between equals() and equalsIgnoreCase()?

equals()	equalsIgnoreCase()
Case-sensitive	Ignores case

34. How do you reverse a string in Java?

Using StringBuilder:

String rev = new StringBuilder(str).reverse().toString();

35. How do you remove duplicates from a string?

Duplicates can be removed using loops, Set collection, or HashSet.

36. How do you count characters in a string?

Using length() method.

str.length();

37. What is an array in Java?

An array is a collection of elements of the same datatype stored in a single variable. It is used to store multiple values together using index positions.

38. What is ArrayList?

ArrayList is a class in Java Collection Framework used to store dynamic collections of elements. Unlike arrays, its size can grow or shrink automatically.

39. What is the difference between Array and ArrayList?

Array	ArrayList
Fixed size	Dynamic size
Stores primitives	Stores objects

40. What is the difference between List, Set, and Map?

41. What is HashMap in Java?

Stores key-value pairs

42. What is the difference between HashMap and Hashtable?

HashMap	Hashtable
Not synchronized	Synchronized

43. What is the difference between HashSet and TreeSet?

HashSet	TreeSet
Unordered	Sorted

44. What is an Iterator in Java?

Used to traverse collection elements.

45. What is the difference between Iterator and ListIterator?

Iterator	ListIterator
Forward only	Forward & backward

46. What is the Collection Framework in Java?

Framework containing classes/interfaces for storing data.

47. What is Comparable and Comparator?

Comparable	Comparator
Natural sorting	Custom sorting

48. What is the difference between ArrayList and LinkedList?

ArrayList	LinkedList
Faster retrieval	Faster insertion/deletion

49. What is exception handling in Java?

Mechanism to handle runtime errors.

50. What is the difference between checked and unchecked exceptions?

Checked	Unchecked
Compile-time	Runtime

51. What is a try-catch block?

Used to handle exceptions.

52. What is a finally block?

Always executes whether exception occurs or not.

53. What is throw and throws keywords?

throw	throws
Throws exception	Declares exception

54. Can a finally block execute without a catch block?

Yes.

55. What is NullPointerException?

Occurs when accessing a null object.

56. What is exception propagation?

Passing an exception from one method to another.

57. What is file handling in Java?

Reading and writing files using Java classes.

58. How do you read data from a file in Java?

Using:

BufferedReader
Scanner
FileReader

59. How do you write data into a file?

Using FileWriter or BufferedWriter.

60. What is BufferedReader?

Used to read text efficiently.

61. What are FileInputStream and FileOutputStream?

Used to read/write byte data.

62. What is multithreading in Java?

Executing multiple threads simultaneously.

63. What is a thread in Java?

Smallest unit of execution.

64. What is the difference between process and thread?

Process	Thread
Independent execution	Part of process

65. How do you create a thread in Java?

Using:

Thread class
Runnable interface

66. What is synchronization?

Prevents multiple threads from accessing shared resources simultaneously.

67. What is thread sleep?

Pauses thread execution temporarily.

68. What are Locators in Selenium?

Locators are used to identify web elements on a webpage so that Selenium can interact with them.

id
name
className
tagName
linkText
partialLinkText
xpath
cssSelector

69. What is XPath, and what are the types of XPath?

XPath is a locator strategy used to navigate through XML/HTML DOM structure.

Types:

Absolute XPath → starts from root (/html/body/...) ❌ not recommended
Relative XPath → flexible and stable (//input[@id='email']) ✅

XPath is useful for:

Dynamic elements
Complex structures

70. What is a page object model?

The Page Object Model (POM) is a design pattern used in test automation that helps you create clean, maintainable, and reusable test code — especially for web applications.

In POM, each web page of your application is represented by a separate class (a “Page Object”), and all the elements (buttons, fields, links, etc.) and actions (clicks, form submissions, etc.) on that page are defined as methods in that class.

Better Code Organization
Keeps UI locators and actions in one place.

Reusability
You can use the same page object in multiple tests.

Easier Maintenance
If a page changes, you update only one file — not all your test scripts.

Improved Readability
Tests become more readable and behave like real-world actions.

71. What is the role of TestNG in Automation Testing?

TestNG is a testing framework that helps organize, execute, and manage automated tests efficiently. It supports features like test grouping, prioritization, parallel execution, and data-driven testing.

It also generates detailed reports and integrates well with tools like Selenium and CI/CD pipelines

72. What are Waits in Selenium?

Waits are used to handle synchronization issues when elements take time to load. Without waits, Selenium may try to interact with elements before they are available, causing failures.

Types:

Implicit Wait → applies globally
Explicit Wait → waits for specific condition
Fluent Wait → customizable

Best practice:
Use Explicit Wait for better control.

73. Difference between Implicit and Explicit Wait

Implicit wait is applied globally and waits for all elements, whereas explicit wait is applied to specific elements based on conditions.

Example:

Wait until element is clickable
Wait until element is visible

Explicit wait is preferred because it is more efficient and avoids unnecessary delays.

74. How do you handle dropdowns?

Dropdowns are handled using the Select class in Selenium when the HTML uses <select> tag.

We can select options using:

Visible text
Value
Index

For custom dropdowns (non-select):
We use click and XPath.

75. How do you handle alerts?

Alerts are popups that require user action. Selenium handles them using switchTo().alert().

Operations:

accept() → click OK
dismiss() → click Cancel
getText() → read message

Important:
You must switch to alert before interacting with it.

76. What is StaleElementException?

This exception occurs when the element is no longer attached to the DOM. It usually happens when

Page refreshes
DOM updates dynamically

Solution:

Re-locate the element
Use explicit wait

77. What is Actions class?

Actions class is used to perform advanced user interactions that cannot be done using simple commands

Examples:

Mouse hover
Drag and drop
Right-click

Used in complex UI scenarios.

78. What is JavaScriptExecutor?

JavaScriptExecutor allows executing JavaScript code inside the browser.

Used when:

Selenium cannot click element
Need to scroll page
Handle hidden elements

Example:

js.executeScript(“window.scrollBy(0,500)”);

79. What is Data-Driven Testing?

In this approach, test data is stored externally (Excel, CSV, JSON), and tests are executed using different data sets.

Benefits:

Reusability
Multiple test scenarios
Better coverage

80. How do you handle failures in automation?

Failures are handled using:

Retry mechanism
Screenshot capture
Logging (Log4j)
Reports (Extent Reports)

81. What are the different types of navigation commands?

Navigation commands are used to move between pages.

Methods:

get() → open URL
navigate().to() → go to URL
navigate().back() → go back
navigate().forward() → go forward
navigate().refresh() → refresh page

82. What is the difference between findElement and findElements?

findElement → returns a single element, throws exception if not found
findElements → returns a list of elements, returns empty list if not found

83. How do you handle frames in Selenium?

Frames are handled using switchTo().frame().

Types:

By index
By name/id
By WebElement

84. What is Page Factory in Selenium?

Page Factory is an extension of POM that uses @FindBy annotation to initialize elements.

85. What is Fluent Wait?

Fluent Wait is an advanced wait with customizable timeout and polling interval.

Features:

Ignore specific exceptions
Set polling frequency

86. What are common exceptions in Selenium?

Examples:

NoSuchElementException
TimeoutException
StaleElementReferenceException
ElementNotInteractableException

87. How do you capture screenshots in Selenium?

Using TakesScreenshot interface.

Used for:

Failure analysis
Reporting

88. How do you scroll a webpage in Selenium?

Using JavaScriptExecutor.

Examples:

scrollBy()
scrollIntoView()

89. How do you handle multiple windows/tabs?

Use getWindowHandles() and switchTo().window()

Steps:

Store window IDs
Switch between them

90. How do you implement retry logic in Selenium?

Using TestNG RetryAnalyzer or custom logic to rerun failed tests.

91. How do you design a scalable automation framework?

Use:

Page Object Model
Reusable utilities
Data-driven approach
Proper logging & reporting

92. What is the difference between Hard Assert and Soft Assert?

Hard Assert → stops execution on failure
Soft Assert → continues execution and reports all failures at end

93. How do you integrate Selenium with CI/CD?

Using tools like:

Jenkins
GitHub Actions

Steps:

Trigger tests on build
Run tests automatically
Generate reports

94. What is logging in Selenium?

Logging helps track test execution.

Tools:

Log4j
SLF4J

95. How do you parameterize tests in TestNG?

Using:

@DataProvider
@Test parameters

96. What are best practices in Selenium automation?

Use stable locators
Avoid Thread.sleep
Use Page Object Model (POM)
Keep tests independent
Maintain reusable code

97.What is broken link?

A broken link is a hyperlink that does not work or leads to an error page (like 404 Not Found), usually because the target page is missing or invalid.

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

driver.close() → closes current browser window
driver.quit() → closes all browser windows and ends session

99. What is getText() vs getAttribute()?

getText() → gets visible text
getAttribute() → gets attribute value (like value, href)

100. What is a WebElement?

WebElement represents an HTML element in Selenium.

Used to perform actions like:

click()
sendKeys()
getText()

101. What is Maven in Selenium?

Maven is a build automation tool.

Used for:

Managing dependencies
Running tests
Project structure

102. What is Jenkins in Selenium?

Jenkins is a CI/CD tool used to automate test execution.

Used for:

Scheduling test runs
Integrating with Git
Generating reports

103. How do you check if an element is displayed on the page?

Methods:

isDisplayed()
isEnabled()
isSelected()

Used for validation in test cases

104. What is the difference between click() and submit()?

click(): Clicks any element
submit(): submit a form

105. How do you handle disabled elements?

Selenium cannot interact directly.

Solution:

Use JavaScriptExecutor
Remove disabled attribute

106. What is the difference between getWindowHandle() and getWindowHandles()?

getWindowHandle(): Returns single window ID
getWindowHandles(): Returns all window IDs

107. How do you handle dynamic tables?

Steps:

Locate table
Use loops for rows and columns
Use dynamic XPath

108. What is the best wait strategy in Selenium?

Best practice:

Use Explicit Wait
Avoid mixing waits
Avoid Thread.sleep()

109. How do you ensure your automation is stable?

Best practices:

Use stable locators
Use waits properly
Keep tests independent

110 .How do you handle auto-suggestions (like Google search)?

Steps:

Enter text
Capture suggestions
Loop and select

111. What is DOM in Selenium?

DOM (Document Object Model) represents the structure of a webpage.

Used for:

Locating elements
Understanding hierarchy

112. How do you handle dynamic elements in Selenium?

Dynamic elements change attributes like id or class at runtime.

Solution:

Use relative XPath
Use functions like: contains() ,starts-with()
Use stable attributes

Example:
//input[contains(@id,’user’)]

113. What will you do if your script fails randomly?

This is called flaky tests.

Approach:

Add proper waits (Explicit Wait)
Check synchronization issues
Verify locators
Add logging and screenshots

114. How do you handle file upload in Selenium?

If input type=”file”:

Use sendKeys() with file path

If custom upload:

Use AutoIT or Robot class

115. How do you handle file download?

Selenium cannot directly handle OS-level downloads.

Solution:

Set browser download preferences
Verify file in download folder

116. How do you validate broken links?

Steps:

Get all links using findElements(By.tagName(“a”))
Use HTTP connection
Check response code

Codes:

200 → OK
404 → Broken

117. How do you scroll to a specific element?

Using JavaScriptExecutor:

scrollIntoView()

118. How do you handle shadow DOM elements?

Shadow DOM elements are hidden inside shadow root.

Solution:

Use JavaScriptExecutor
Access shadowRoot

119. What is the difference between driver.get() and driver.navigate().to()?

get():

Waits for page load
Used for initial load

navigate().to():

Similar but used for navigation

120. How do you run tests in parallel in Selenium?

Using TestNG:

parallel=”methods” or “classes” in XML
Use Selenium Grid

121. How do you manage test data?

Using:

Excel (Apache POI)
JSON
DataProvider in TestNG

122. How do you handle stale element exceptions in real projects?

Solution:

Re-locate element
Use Explicit Wait
Avoid storing WebElement for long

123. What challenges did you face in automation?

Dynamic elements
Synchronization issues
Browser compatibility
Slow execution

124. How do you identify if an element is not clickable?

Check:

Visibility
Enabled state
Overlapping elements

Use:

Explicit Wait → elementToBeClickable

125. How do you debug a failed test case?

Steps:

Check logs
Check screenshots
Re-run test
Validate locators
Check environment

126. How do you handle cookies in Selenium?

Methods:

addCookie()
getCookies()
deleteCookie()

127. How do you integrate your framework with CI/CD?

Steps:

Push code to Git
Configure Jenkins job
Trigger build
Run tests
Generate report

128. How do you capture screenshots only on failure?

Using:

TestNG listeners (ITestListener)
Take screenshot in onTestFailure()

129. What is the difference between Absolute and Relative path?

Absolute:

Full path
Not stable

Relative:

Flexible
Recommended

130. Your test works in Chrome but fails in Firefox. What will you do?

Possible reasons:

Different browser behavior
Locator compatibility issues
Timing issues

Solution:

Use cross-browser compatible locators
Add explicit waits
Use browser-specific options if needed

131. Element is visible but Selenium is unable to click it. Why?

Possible causes:

Element overlapped by another element
Element not clickable yet
Hidden behind loader

Solution:

Use Explicit Wait → elementToBeClickable
Scroll into view
Use JavaScriptExecutor click as fallback

132. Your XPath is correct but still element is not found. What could be wrong?

Reasons:

Element inside iframe
Element inside shadow DOM
Page not fully loaded

Solution:

Switch to frame
Handle shadow root
Use wait

133. How do you automate a page where elements load after scrolling?

Solution:

Use JavaScriptExecutor to scroll
Load elements dynamically
Use loop until element appears

134. How do you handle a situation where element ID changes every time?

Solution:

Use contains() or starts-with()
Use parent-child XPath
Use other stable attributes

135. Your test passes locally but fails in Jenkins. Why?

Common reasons:

Environment difference
Headless mode issues
Timing issues

Solution:

Add proper waits
Check environment configs
Add logging

136. How do you design your framework for multiple users/logins?

Solution:

Use DataProvider
Store test data externally
Parameterize login

137. How do you handle a calendar/date picker?

Types:

Simple → sendKeys()
Complex → click through UI

Steps:

Open calendar
Navigate month/year
Select date

138. How do you handle pagination (multiple pages)?

Solution:

Loop through pages
Click “Next” button
Extract data until last page

139. How do you verify if a file is successfully downloaded?

Steps:

Set download directory
Check file existence
Validate file name

140. What will you do if execution is very slow?

Optimization:

Run tests in parallel
Remove Thread.sleep()
Use headless mode
Optimize locators

141. How do you handle dependency between test cases?

Solution:

Avoid dependency (best practice)
Use TestNG dependsOnMethods if needed

142. How do you test a login page with multiple invalid inputs?

Approach:

Use DataProvider
Pass multiple datasets

Example:

Invalid username
Invalid password
Empty fields

143. What if application UI changes frequently?

Solution:

Use POM design
Centralize locators
Use stable attributes

144. How do you validate error messages?

Steps:

Capture element text
Compare with expected

Use:

assertEquals()

145. What are the test types supported by Selenium?

For testing web-based applications, Selenium can be used.

The test types supported by Selenium are:

Functional testing: It verifies if each function of a software application performs in accordance with specific requirements. This testing primarily involves black-box testing, and it is not concerned with the source code of the application.
Regression testing: It is nothing but a full or partial selection of the already executed test cases to be re-executed to ensure that the existing functionalities work fine.

146. In Selenium, what are breakpoints and start points?

Breakpoints: Breakpoints are used to stall the execution of the test. The execution will stop whenever a breakpoint is implemented, and this will help us check whether the code is working properly or not.

Start points: Start points are the points from where the execution should begin. Start points can be used when we want to run the test script from the middle of the code or after a breakpoint.

147. What is DOM inspection?

Inspecting webpage structure using browser DevTools.

Used for:

Locators
XPath
CSS selectors

148. What are the latest features in Selenium 4?

Features:

Relative locators
Selenium Manager
Improved Grid
Better DevTools support
New window/tab handling

149. What is smoke suite in automation?

Small set of critical test cases executed after every build.

Purpose:

Verify build stability quickly.

150. What is a locator strategy hierarchy?

Preferred locator order:

ID
Name
CSS Selector
XPath

Because IDs are fastest and most stable.

151. What are flaky tests?

Tests that:

Pass sometimes
Fail sometimes

Reasons:

Timing issues
Dynamic elements
Environment instability

152. How do you reduce flaky tests?

Use explicit waits
Stable locators
Retry mechanism
Proper synchronization
Independent tests

153. What metrics do you track in automation?

Pass/fail percentage
Automation coverage
Execution time
Defect leakage
Stability rate

154. What reporting tools are used with Selenium?

Popular reporting tools:

Extent Reports
Allure Reports
TestNG Reports

155. What is Extent Report?

Advanced HTML reporting library used for:

Logs
Screenshots
Execution reports

156. What is the difference between verification and validation?

*Verification*	*Validation*
Checks whether product is built correctly	Checks whether correct product is built
Process-oriented	Product-oriented

157. What is ThreadLocal in Selenium?

Used in parallel execution to maintain separate WebDriver instances per thread.

Example use:

Parallel test execution in TestNG

158. How do you automate OTP-based login?

Usually OTP is not automated directly.

Approaches:

Disable OTP in test environment
Fetch OTP from database/API/email
Use static OTP in lower environments

159. What if developer changes locator frequently?

Use relative XPath/CSS
Coordinate with developers
Add stable attributes like data-testid

160. How do you validate large datasets in UI?

Database comparison
API validation
Dynamic table handling

161. What if test data is unavailable?

Approaches:

Generate test data dynamically
Use APIs/database
Mock services

162. How do you manage secrets/passwords in framework?

Never hardcode credentials.

Use:

Environment variables
Vault tools
Encrypted config

163. How do you validate images on webpage?

Check:

Image displayed
HTTP response
Natural width > 0

164. How do you handle hidden elements?

Using:

JavaScriptExecutor
Actions class
Wait until visible

165.What will you do if there are no unique locators?

Use:

Relative XPath
Parent-child relationship
CSS hierarchy
Multiple attributes

166. What is a Keyword-Driven Framework?

A Keyword-Driven Framework is an automation framework where test actions are represented using predefined keywords like Click, Type, and Login.

The test data, locators, and actions are maintained separately from the test scripts, making the framework more reusable, maintainable, and easy to understand.

167. What is TestNG?

TestNG (Test Next Generation) is a testing framework inspired by JUnit and NUnit but designed to be more powerful and flexible. It supports annotations, parallel execution, data-driven testing, and reporting.

168. What are the main features of TestNG?

Annotation-based testing
Parallel test execution
Data-driven testing using DataProvider
Flexible test configuration
Dependency management
Detailed reporting

169. What are TestNG annotations?

Annotations define how methods should behave in a test. Common ones include:

@Test – marks a test method
@BeforeMethod / @AfterMethod
@BeforeClass / @AfterClass
@BeforeSuite / @AfterSuite

170. What is the difference between @BeforeMethod and @BeforeClass?

@BeforeMethod: runs before each test method
@BeforeClass: runs once before all test methods in a class

171. What is the difference between TestNG and JUnit?

TestNG	JUnit
Supports parallel execution	Limited parallel support
Supports dependency testing	No dependency feature
Supports DataProvider	Limited parameterization
More flexible annotations	Fewer annotations
Better reporting	Basic reporting

172. What is testng.xml file?

testng.xml is a configuration file used to control test execution in TestNG.

It helps to:

Define test suites
Group tests
Run tests in parallel
Pass parameters
Control execution order

Example:

<suite name="Suite">
  <test name="Test">
     <classes>
        <class name="tests.LoginTest"/>
     </classes>
  </test>
</suite

173. What are groups in TestNG?

Groups are used to categorize test methods.

Example:

@Test(groups = "smoke")
public void loginTest() {
}

You can run only specific groups using testng.xml.

174. What is the use of `dependsOnGroups` in TestNG?

It allows a test method to depend on an entire group of tests.

Example:

Groups are used to categorize test methods.

Example:

@Test(groups = "smoke")
public void loginTest() {
}

You can run only specific groups using testng.xml.

175. What is dependency in TestNG?

Dependency means one test method depends on another test method.

Example:

@Test
public void login() {
}

@Test(dependsOnMethods = "login")
public void dashboard() {
}

If login() fails, dashboard() will be skipped.

176. What is the difference between Hard Assert and Soft Assert?

Hard Assert

Stops execution immediately if assertion fails.

Assert.assertEquals(actual, expected);

Soft Assert

Continues execution even after assertion failure.

SoftAssert sa = new SoftAssert();
sa.assertEquals(actual, expected);
sa.assertAll();

177. What is assertion in TestNG?

Assertions are used to validate expected and actual results.

Common assertions:

assertEquals()
assertTrue()
assertFalse()
assertNull()

178. What is parameterization in TestNG?

Parameterization allows passing values to test methods from testng.xml.

Example:

<parameter name="browser" value="chrome"/>
@Parameters("browser")
@Test
public void launch(String browser) {
}

179. What is the difference between Parameters and DataProvider?

Parameters	DataProvider
Values from XML	Values from Java method
Used for simple data	Used for multiple datasets
Less flexible	More flexible

180. How can you run tests in parallel in TestNG?

Using parallel attribute in testng.xml.

Example:

<suite name="Suite" parallel="tests" thread-count="2">

181. What is invocationCount in TestNG?

It is used to run a test multiple times.

Example:

@Test(invocationCount = 5)
public void testMethod() {
}

182. What is priority in TestNG?

Priority controls execution order of test methods.

Example:

@Test(priority = 1)
public void login() {
}

@Test(priority = 2)
public void logout() {
}

Lower priority executes first.

183. What happens if priority is not set?

Test methods execute in alphabetical order by method name.

184. What is timeout in TestNG?

Timeout defines maximum execution time for a test.

Example:

@Test(timeOut = 3000)
public void test() {
}

Test fails if execution exceeds 3 seconds.

185. What is enabled=false in TestNG?

Used to skip a test method.

Example:

@Test(enabled = false)
public void skipTest() {
}

186. What is the difference between @BeforeTest and @BeforeSuite?

@BeforeTest	@BeforeSuite
Runs before test tag	Runs before entire suite
Executes multiple times	Executes once

187. How do you skip a test in TestNG?

Two ways:

enabled = false
Using SkipException

Example:

throw new SkipException("Skipping test")

188. What are listeners in TestNG?

Listeners are interfaces that modify TestNG behavior during execution.

Common listeners:

ITestListener
ISuiteListener

Used for:

Logging
Screenshots
Reporting

189. What is ITestListener?

It is a listener interface used to track test execution events.

Methods include:

onTestStart()
onTestSuccess()
onTestFailure()

190. How do you generate reports in TestNG?

TestNG automatically generates reports inside the test-output folder.

Main reports:

index.html
emailable-report.html

191. What is factory annotation in TestNG?

@Factory is used to create multiple instances of test classes dynamically.

192. What is the difference between @BeforeTest and @BeforeMethod?

@BeforeTest	@BeforeMethod
Runs before all test methods in a test	Runs before each test method
Executes once	Executes multiple times

193. Can TestNG be integrated with Selenium?

Yes. TestNG is widely used with Selenium for:

Test execution
Reporting
Assertions
Parallel testing
Data-driven testing

194. How do you retry failed test cases in TestNG?

Using IRetryAnalyzer.

Example:

public class Retry implements IRetryAnalyzer {
  int count = 0;

  public boolean retry(ITestResult result) {
     if(count < 2) {
        count++;
        return true;
     }
     return false;
  }
}

195. What is alwaysRun=true in TestNG?

It ensures the method executes even if dependent methods fail.

Example:

@Test(alwaysRun = true)

196. What is thread-count in TestNG?

It defines the number of threads used during parallel execution.

Example:

thread-count="3"

197. What is Page Object Model (POM)?

Page Object Model is a design pattern in Selenium automation where each web page is represented as a separate class.
The class contains:

Web elements of the page
Methods to perform actions on those elements

It helps improve:

Code reusability
Maintainability
Readability

198. Why do we use POM in Selenium?

POM is used to:

Reduce code duplication
Separate test logic from page elements
Make framework easy to maintain
Handle UI changes easily
Improve scalability of automation framework

199. What are the main components of POM?

Main components are:

Page Class → Contains locators and methods
Test Class → Contains test cases
Object Repository → Stores web element locators

200. What are the advantages of POM?

Advantages:

Better code organization
Easy maintenance
Reusable methods
Improved readability
Reduced duplication
Easy debugging

201. How does POM improve maintainability?

If a locator changes in UI, we update it only in the Page Class instead of updating in all test cases.

202. What is Page Factory in Selenium?

Page Factory is an inbuilt Selenium class used to implement POM easily using annotations like @FindBy.

Example:

@FindBy(id="username")
WebElement userName;

203. Difference between POM and Page Factory?

POM	Page Factory
Uses normal findElement()	Uses @FindBy annotations
Elements initialized manually	Elements initialized automatically
More coding required	Less coding required
Slower compared to Page Factory	Faster initialization

204. What is the use of @FindBy annotation?

@FindBy is used to locate web elements in Page Factory.

Example:

@FindBy(xpath="//input[@id='email']")
WebElement email;

205. What is PageFactory.initElements()?

It initializes all web elements present in the Page Class.

Example:

PageFactory.initElements(driver, this);

206. How do you create a Page Class in POM?

Example:

public class LoginPage {
   WebDriver driver;
   @FindBy(id="username")
   WebElement username;
   @FindBy(id="password")
   WebElement password;
   @FindBy(id="login")
   WebElement loginBtn;
   LoginPage(WebDriver driver){
       this.driver = driver;
       PageFactory.initElements(driver, this);
   }

   public void login(String user, String pass){
       username.sendKeys(user);
       password.sendKeys(pass);
       loginBtn.click();
   }
}

207. What is the role of constructor in POM?

Constructor is used to:

Initialize WebDriver
Initialize web elements using PageFactory

208. Can we use POM without Page Factory?

Yes.
We can implement POM using normal findElement() methods without using Page Factory.

209. What is the difference between Page Class and Test Class?

Page Class	Test Class
Contains locators and methods	Contains test cases
Represents webpage	Executes validations
Reusable	Uses page methods

210. How does POM support reusability?

Common methods like login, click, search, etc. can be reused across multiple test cases.

211. What type of framework commonly uses POM?

POM is commonly used in:

Hybrid Framework
Data-Driven Framework
Keyword-Driven Framework

212. What are best practices in POM?

Keep locators private
Use meaningful method names
Avoid hard coding
Use reusable methods
Maintain separate test and page classes

213. How do you handle dynamic elements in POM?

Dynamic elements can be handled using:

Dynamic XPath
Explicit waits
Relative locators

Example:

@FindBy(xpath="//button[contains(text(),'Login')]")
WebElement loginBtn;

214. Can POM be used with TestNG?

Yes.
POM is commonly integrated with TestNG for test execution, assertions, and reporting.

215. Why is POM considered a good design pattern?

Because it follows:

Separation of concerns
Encapsulation
Reusability
Maintainability

216. What is encapsulation in POM?

Web elements are hidden inside Page Classes and accessed only through methods.

Example:

public void clickLogin(){
   loginBtn.click();
}

217. How do you manage waits in POM?

Waits are usually implemented inside page methods using Explicit Wait.

Example:

WebDriverWait wait = new WebDriverWait(driver, Duration.ofSeconds(10));
wait.until(ExpectedConditions.visibilityOf(loginBtn));

218. How do you handle multiple pages in POM?

Create separate Page Classes for each webpage.

Example:

LoginPage.java
HomePage.java
CartPage.java

219. What is Base Class in POM framework?

Base Class contains common setup code like:

Browser launch
Driver initialization
Wait setup
Common utilities

220. What are reusable methods in POM?

Methods that can be used multiple times across tests.

Example:

click()

sendKeys()

selectDropdown()

221. How is POM useful in large projects?

In large projects:

UI changes happen frequently
Multiple testers work together
Reusable components are needed

POM helps manage all these efficiently.

222. Explain real-time usage of POM.

In real projects:

Every page has separate class
Test cases call page methods
Framework becomes modular and scalable
Maintenance becomes easier when UI changes occur

223. What is Log4j?

Log4j is a Java-based logging framework used to generate application logs for debugging, monitoring, and troubleshooting.

224. Why is logging important in automation testing?

Logging helps:

Track test execution
Identify failures
Debug issues easily
Monitor application behavior

225. What are the main components of Log4j?

Logger
Appender
Layout

226. What is a Logger in Log4j?

Logger is used to capture logging information in the application.

Example:

Logger log = Logger.getLogger(Test.class);

227. What is an Appender?

Appender decides where logs will be stored.

Examples:

ConsoleAppender
FileAppender
RollingFileAppender

228. What is a Layout in Log4j?

Layout defines the format of log messages.

Example:

%d [%t] %-5p %c - %m%n

229. What are the different log levels in Log4j?

Log Level	Purpose
ALL	Logs everything
TRACE	Detailed information
DEBUG	Debugging information
INFO	General information
WARN	Warning messages
ERROR	Error messages
FATAL	Critical errors
OFF	Turns off logging

230. What is the use of log4j.properties file?

It is used to configure:

Log levels
Appenders
Layouts
Log file location

231. How do you configure Log4j?

Example:

log4j.rootLogger=INFO, file

log4j.appender.file=org.apache.log4j.FileAppender
log4j.appender.file.File=logs/application.log
log4j.appender.file.layout=org.apache.log4j.PatternLayout

231. How do you print logs in Log4j?

Example:

log.info("Test Started");
log.error("Test Failed");
log.debug("Debug Message");

233. What is the difference between INFO and DEBUG?

INFO → General execution information
DEBUG → Detailed debugging information for developers

234. What is RollingFileAppender?

It creates new log files when file size reaches a limit.

235. What is the advantage of using RollingFileAppender?

Prevents large log files
Improves log management
Creates backup log files automatically

236. What is PatternLayout?

PatternLayout formats log messages in a customizable pattern.

Example:

%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n

237. How is Log4j used in Selenium Automation Framework?

Log4j is used to:

Log test execution steps
Capture pass/fail status
Store exception details
Debug automation scripts

238. How do you integrate Log4j with Selenium?Steps:

Add Log4j dependency
Create log4j.properties file
Configure logger in Java class
Use logging methods

239. What dependency is required for Log4j in Maven?

Example:

<dependency>
    <groupId>log4j</groupId>
    <artifactId>log4j</artifactId>
    <version>1.2.17</version>
</dependency>

240. What is the difference between Log4j and System.out.println()?

Log4j	System.out.println
Professional logging	Simple console printing
Supports log levels	No log levels
Can store logs in files	Only console output
Better for frameworks	Not suitable for large projects

241. What is Root Logger?

Root Logger is the default logger that controls all child loggers.

Example:

log4j.rootLogger=DEBUG, console

242. What is the difference between Log4j1 and Log4j2?

Log4j2 is faster
Better performance
Supports asynchronous logging
Improved security