EPAM Interview Questions and Answers for Automation Testing

I have shared my interview experience with the EPAM Software company for the QA Lead position below. The following are the technical interview questions and answers discussed during the round.

Question 1: Please Explain yourself and Roles and responsibilities in the previous project

Answer:

This is the common question in most of the interviews. We can explain about our experience and roles and responsibilities in our recent project.

Question 2: How to find Duplicate characters in a String using Selenium and Java?

Answer:

We can find the duplicate characters of String in different ways such as using HashMap, Set or char array. I have explained scenario about using HashMap. Here I am going to provide the code using HashMap and Set below for finding duplicate characters using char array you can go through the video suggested in the description.

Using HashMap:

import java.util.HashMap;

import java.util.Map;

import org.openqa.selenium.By;

import org.openqa.selenium.WebDriver;

import org.openqa.selenium.chrome.ChromeDriver;

import org.testng.annotations.Test;

public class DuplicateCharacters {

@Test

public void verifyDuplicates {

WebDriver driver = new ChromeDriver();

driver.get(“https://example.com”);

// Get text from a web element

String text = driver.findElement(By.id(“sampleText”)).getText();

// Remove spaces and convert to lowercase (optional)

text = text.replaceAll(“\\s”, “”).toLowerCase();

// HashMap to store character count

HashMap<Character, Integer> charCount = new HashMap<>();

for (char ch : text.toCharArray()) {

charCount.put(ch, charCount.getOrDefault(ch, 0) + 1);

}

// Print duplicate characters

System.out.println(“Duplicate characters are:”);

for (Map.Entry<Character, Integer> entry : charCount.entrySet()) {

if (entry.getValue() > 1) {

System.out.println(entry.getKey() + ” : ” + entry.getValue());

}

driver.quit();

}

Using Set:

import java.util.HashSet;

import java.util.Set;

String text = “selenium”;

Set<Character> seen = new HashSet<>();

Set<Character> duplicates = new HashSet<>();

for (char ch : text.toCharArray()) {

if (!seen.add(ch)) {

duplicates.add(ch);

}

System.out.println(“Duplicate characters: ” + duplicates);

Question3: What is the use of Lamda expression how to use it in previous scenario from Question 2?

Answer:

I have explained use of Lamda expression as part previous program with HashMap for duplicate characters

A lambda expression is used to write cleaner, shorter, and more readable code by providing an implementation of a functional interface without creating a separate class or method.

import java.util.HashMap;

import java.util.Map;

import org.openqa.selenium.By;

import org.openqa.selenium.WebDriver;

import org.openqa.selenium.chrome.ChromeDriver;

import org.testng.annotations.Test;

public class DuplicateCharacters {

@Test

public void verifyDuplicates {

WebDriver driver = new ChromeDriver();

driver.get(“https://example.com”);

// Get text from a web element

String text = driver.findElement(By.id(“sampleText”)).getText();

// Remove spaces and convert to lowercase

text = text.replaceAll(“\\s”, “”).toLowerCase();

// HashMap to store character count

HashMap<Character, Integer> charCount = new HashMap<>();

for (char ch : text.toCharArray()) {

charCount.put(ch, charCount.getOrDefault(ch, 0) + 1);

}

System.out.println(“Duplicate characters are:”);

charCount.forEach((key, value) -> {

if (value > 1) {

System.out.println(key + ” : ” + value);

}

});

driver.quit();

}

Question 4: What is the difference between Post and PUT methods? – Api Testing

Answer:

Difference Between POST and PUT Methods (REST / HTTP)

Feature	POST	PUT
Purpose	Create a new resource	Update or replace an existing resource
Resource URI	Server decides the URI	Client specifies the URI
Idempotent	❌ No (multiple requests create multiple resources)	✅ Yes (multiple requests give same result)
Data Handling	Adds new data	Replaces existing data completely
Repeat Request Effect	Creates duplicates	No duplicate creation
Response	Usually returns 201 Created	Usually returns 200 OK or 204 No Content
Example URL	/users	/users/101

Question 5: When do we receive 401 and 500 status codes in api testing?

Answer:

🔹 401 – Unauthorized

✅ When it occurs

You receive 401 when the client is not authenticated or authentication is invalid.

Common reasons

Missing Authorization header
Invalid username/password
Expired or invalid JWT / OAuth token
Incorrect API key
Token format is wrong

Example

GET /users

Authorization: Bearer invalid_token

Response

401 Unauthorized

Interview Line

401 means the request is not authenticated. The server refuses access because credentials are missing or invalid.

🔹 500 – Internal Server Error

✅ When it occurs

You receive 500 when the server fails to process a valid request due to an internal issue.

Common reasons

Null pointer or unhandled exception in backend code
Database connection failure
Server crash
Incorrect server configuration
Code bug

Example

POST /users

Body: 
{

  "name": null

}

Question 6: Explain one scenario for API test automation?

Answer:

I have explained an API automation scenario for verification with Get request as below

🔹 API Details

Method: GET
URL: {{baseUrl}}/users/{{userId}}
Authorization: Bearer Token
Headers:
- Content-Type: application/json

1. Verify Status Code

pm.test(“Status code is 200”, function () {

pm.response.to.have.status(200);

});

2. Verify Response Time

pm.test(“Response time is less than 2000ms”, function () {

pm.expect(pm.response.responseTime).to.be.below(2000);

});

3. Verify Content-Type Header

pm.test(“Content-Type is application/json”, function () {

pm.response.to.have.header(“Content-Type”);

pm.expect(pm.response.headers.get(“Content-Type”))

.to.include(“application/json”);

});

4. Verify Response Body is not empty

pm.test(“Response body is not empty”, function () {

pm.expect(pm.response.json()).to.not.be.empty;

});

5. Verify User ID

pm.test(“User ID is correct”, function () {

var jsonData = pm.response.json();

pm.expect(jsonData.id).to.eql(parseInt(pm.environment.get(“userId”)));

});

6. Verify Mandatory Fields

pm.test(“Mandatory fields are present”, function () {

var jsonData = pm.response.json();

pm.expect(jsonData).to.have.property(“name”);

pm.expect(jsonData).to.have.property(“email”);

});

7. Verify Data Types

pm.test(“Verify data types”, function () {

var jsonData = pm.response.json();

pm.expect(jsonData.id).to.be.a(“number”);

pm.expect(jsonData.name).to.be.a(“string”);

pm.expect(jsonData.email).to.be.a(“string”);

});

Watch YouTube Video here: EPAM interview questions for automation testing