Full Stack Interview - FAQ & Answers

Linux Mint - Cinnamon - Developer setup 1.  Git client $ apt install git $ git --version 2.  Google chrome https://support.google.com/chrome/a/answer/9025926?sjid=1869230896922332783-NC https://www.digitalocean.com/community/tutorials/install-chrome-on-linux-mint 3. Visual Studio Code 4. Optimize Linux Mint: Must-Do Tweaks After Setup  https://www.youtube.com/watch?v=D9OfpxFgR08 Commands: $ neofetch --IJ IDE ---IJ Download Community Edition https://www.jetbrains.com/idea/download/?section=linux sudo tar -xzf ideaIC-2025.2.2.tar.gz -C /opt https://www.youtube.com/watch?v=v2zrDCDs2yU&pp=ygUzSW50ZWxsaUogSURFQSBDb21tdW5pdHkgRWRpdGlvbiBjaW5uYW1vbiBsaW51eCBtaW50 --Eclipse download https://www.youtube.com/watch?v=KHUZAg_0O5k&pp=ygUtRWNsaXBzZSBDb21tdW5pdHkgRWRpdGlvbiBjaW5uYW1vbiBsaW51eCBtaW50 ---KDE connect For transfer files https://www.youtube.com/watch?v=AgC1CVHDZFs

Frequently used Spring Boot Annotation with details and its usage category wise: 1] Core: @SpringBootApplication : Bootstrap the app with default configurations, auto-config, component scan - Used on Main class   @ComponentScan : Scan specific packages for Spring beans - Used on Config/Main class @Configuration  : Define Spring beans in Java config - Config class @Bean : Declare & customize a bean manually - Method inside & config class @Value : Inject values from application.properties file - Field, setter, constructor @PropertySource : Load external properties file - Config class 2] DI (Dependency Injection) : @Autowired  : Auto inject dependencies by type -  Field, setter, constructor @Qualifier  : Specify which bean to inject if multiple -  Field, Param @Primary  : Mark default bean when multiple type is exist -  Bean class or method @Inject  : Java standard alternatives to @Autowired -  Field @Resource  : Inject be...

1. Performance Testing & Setting up benchmarks Performance testing evaluate how a system performs under load & to setup benchmarks below steps to be noted down. Steps are: Define KPIs: Response time, throughput, CPU/memory usage etc. Identify Critical Scenarios: like login, search, submit form Use Tools: Gatling, Apache Bench, JMeter (Use to simulate 1000 concurrent users hitting a Rest API and measure the response time Baseline Measurement: Run tests under normal load to establish a baseline Load Testing: Gradually increase users to find system limits Stress Testing: Push beyond limits to see how the system fails Bench marking: Compare results against industry standards or previous releases 2. ACID properties in database It ensure the reliable transaction Atomicity : All operations in a transaction succeed or none do Consistency : DB remains in a valid state before and after the transaction Isolation : Concurrent transactions don't interfere Durability : Once commited...

1] Arrays 1] Find first and second best score Example Given an array, write a function to get first, second best scores from the array and return it in new array. Array may contain duplicates. Example myArray = { 84 , 85 , 86 , 87 , 85 , 90 , 85 , 83 , 23 , 45 , 84 , 1 , 2 , 0 } firstSecond ( myArray ) // {90, 87} Solution: import java . util . Arrays ; import java . util . Collections ; public class Exercise { public static int [] findTopTwoScores ( int [] array ) { int firstHighest = Integer . MIN_VALUE ; int secondHighest = Integer . MIN_VALUE ;   for ( int score : array ) { if ( score > firstHighest ) { secondHighest = firstHighest ; firstHighest = score ; } else if ( score > secondHighest && score < firstHighest ) { secondHighest = score ; } }   return new int []{ firstHighest , secondHighest }...