SDET / QA — 300 Most-Asked Interview Questions (with Answers & Examples)¶
Source: the "SDET QA (Q&A)" list by Junaid Aziz (credit: @Kushal Parikh for the Selenium coding challenges). Every question is answered here in simple English with a definition → plain-words explanation → concrete example/code, so you can read it, cover the answer, and say it out loud.
How to use: pick one file, read a question, cover the answer, speak it. The bold words are what the interviewer is listening for.
Sections (10 × 30 = 300 questions)¶
| # | File | Topic | Answer style |
|---|---|---|---|
| 1 | 01_Manual_Testing.md | Manual Testing (concepts + scenarios) | Definition → gloss → example; scenario Qs as speakable STAR mini-scripts |
| 2 | 02_Java_Core.md | Java (language) | Definition → why it matters → tiny code diff |
| 3 | 03_Java_OOPs.md | Core Java OOP concepts | Concept → analogy → minimal example |
| 4 | 04_Java_Coding.md | Java coding for SDET | Full working method + approach + say-it-aloud |
| 5 | 05_Selenium_WebDriver.md | Selenium WebDriver | Definition → runnable snippet → gotcha |
| 6 | 06_Maven.md | Maven | Definition → where it fits → command / pom snippet |
| 7 | 07_TestNG.md | TestNG | Definition → annotation/XML snippet → tip |
| 8 | 08_Cucumber_BDD.md | Cucumber BDD | Definition → Gherkin/glue snippet → why BDD |
| 9 | 09_Page_Object_Model.md | Page Object Model | Concept → POM/PageFactory snippet → best-practice |
| 10 | 10_Selenium_Coding_Challenges.md | Real-time Selenium coding challenges | Complete working method + one-line explanation |
| 11 | 11_Challenges_Faced_And_How_I_Coped.md | "Challenges faced & how I coped" — Java, Python, Playwright, API, UI | STAR stories grounded in real projects + 🎤 say-this + template |
| 12 | 12_Frameworks_And_Libraries_By_Language.md | Frameworks & libraries by language (Java/Python/TS + tools) | What each library does + where you used it; don't-over-claim notes |
| 13 | 13_How_To_Explain_Framework_Libraries_Tools.md | Framework/Libraries/Tools answered per project (REST Assured, Playwright, Python, Java UI+API) | Clean Framework→Libraries→Tools tables per project + 🎤 say-this |
| 14 | 14_Scenario_Interview_Rounds.md | Scenario round (8 API/automation scenarios: Jenkins-vs-local, dynamic price vs API, file upload/download, UI↔API pagination, token expiry, REST Assured validation, retry/429-500, prod RCA) + Round 3 Managerial + Round 4 HR/Salary | Approach → code → say-it; STAR + negotiation scripts. PDF in pdf/ |
How I planned each section¶
- Concept questions (Manual, Java, OOP, Maven, TestNG, Cucumber, POM): keep each answer interview-length (2–6 sentences) — a crisp definition first (what the interviewer scores), then a plain-English "in other words," then one concrete example. Comparison questions ("X vs Y") use a 2-column contrast so the difference is instant.
- Coding questions (Java coding, Selenium challenges): give complete, compilable code (not pseudo-code), plus a one-line note on the approach and, where relevant, time/space complexity — so you can both write it and explain it.
- Scenario / behavioural questions ("bug in production", "developer disagrees", "no requirements"): answered as short speakable scripts using a mini-STAR shape, so you sound calm and structured, not theoretical.
- Cross-links: deeper theory already lives in the parent folder — e.g. ../04_Manual_Testing_SDLC_STLC.md, ../05_Selenium_Concepts.md, ../09_API_Testing_RestAssured.md, ../20_Software_Testing_Concepts_NPTEL.md. This set is the fast, memorizable layer on top.
Quick revision order (if short on time)¶
- Manual Testing (asked in ~90% of QA/SDET rounds)
- Java Core + OOPs (fundamentals gate)
- Selenium WebDriver + POM (the framework story)
- TestNG + Maven (the "how it runs" story)
- Java coding + Selenium challenges (the coding round)
- Cucumber BDD (only if the JD mentions BDD)