Katalon, Playwright, Java — Interview Practice

Katalon Studio

Q1. What is Katalon Studio, and how is it different from Selenium?

Katalon Studio is a complete test automation platform built on top of Selenium and Appium. Unlike Selenium, which is just a library for web automation, Katalon provides an IDE, built-in keywords, test case management, reporting, and integrations with CI/CD tools. This makes it easier for testers to create and manage automated tests without writing too much code.

Q2. How do you handle test data in Katalon Studio?

In Katalon Studio, test data can be handled using different approaches. We can store it in Excel, CSV, or database files and then bind it to test cases for data-driven testing. Katalon also provides built-in Data Files and Global Variables that allow parameterization and reuse of data across multiple test cases.

Playwright

Q3. What advantages does Playwright have over Selenium or Puppeteer?

Playwright comes with bundled browser binaries, so you don’t need to install drivers like Selenium. It supports multiple browsers (Chromium, Firefox, WebKit) with a single API, unlike Puppeteer which is Chromium-only. Playwright also has auto-waiting, handles modern web apps (SPA, shadow DOM), and supports multiple contexts for parallel testing.

Q4. How do you handle multiple browser contexts or parallel execution in Playwright?

In Playwright, we can create independent browser contexts within a single browser instance. Each context has its own cookies and storage. For parallel execution, Playwright Test runner runs tests in multiple workers using CPU cores, improving execution speed.

Java (for Test Automation)

Q5. Explain OOP concepts in Java and how they apply in test automation.

The four OOP pillars in Java are:

• Encapsulation: Grouping variables and methods in classes (e.g., Page Object Model).
• Inheritance: Reusing code from base classes (e.g., setup/teardown).
• Polymorphism: Same method behaving differently (e.g., method overriding).
• Abstraction: Hiding details, exposing only necessary features (e.g., abstract class for browsers).

Q6. How do you handle exceptions in Java test scripts?

Exceptions are handled with try-catch-finally. Checked exceptions must be handled at compile time, while unchecked occur at runtime. In automation, exception handling helps log errors, take screenshots, close browsers, or retry failed steps.