600+ Legend Holidays Interview Questions and Answers

System Engineer interview questions covering tech stacks, Java, Spring, Hibernate, REST, and API security.

• Tech stacks include Java, Spring, Hibernate, REST, and API security.

• Class loader loads classes into JVM at runtime.

• Auto Configuration automatically configures Spring beans based on classpath and other conditions.

• An object is an instance of a class that has state and behavior.

• Exceptions in Spring can be handled using try-catch blocks or using @ExceptionHandler annotation.

• I...read more

Cut the cake horizontally twice and then vertically once.

• Cut the cake horizontally into two equal halves.

• Stack the two halves and cut horizontally again to get four equal pieces.

• Finally, cut vertically through the center to get eight equal pieces.

Procedural programming focuses on procedures and functions, while OOP emphasizes objects and classes.

• Procedural programming uses a top-down approach, while OOP uses a bottom-up approach.

• In procedural programming, data and functions are separate, while in OOP, they are encapsulated within objects.

• Procedural programming is more suitable for small-scale programs, while OOP is better for large-scale projects.

• C is a procedural programming language, lacking the features of OOP like...read more

A constructor is a special method used to initialize an object, while a method is a function that performs a specific task.

• Constructors are called automatically when an object is created, while methods need to be called explicitly.

• Constructors have the same name as the class, while methods can have any valid name.

• Constructors do not have a return type, while methods can have a return type.

• Constructors are used to set initial values of instance variables, while methods are use...read more

Modeling an upsetting operation involves understanding process parameters and their relationships.

• Upsetting is a metal forming process that involves compressing a metal workpiece to reduce its length and increase its diameter.

• Process parameters include temperature, pressure, and deformation rate.

• Temperature affects the material's flow stress and ductility, while pressure and deformation rate affect the material's strain hardening behavior.

• The relationship between these parame...read more

Protocols are a set of rules that govern the communication between devices or systems.

• Protocols define the format, timing, sequencing, and error checking of messages exchanged between devices.

• Different types of protocols include network protocols (TCP/IP, HTTP, FTP), communication protocols (RS-232, USB, Bluetooth), and application protocols (SMTP, POP3, IMAP).

• Network protocols govern the communication between devices on a network, while communication protocols govern the com...read more

Assignment is assigning a value to a variable, while initialization is declaring and assigning a value to a variable.

• Assignment changes the value of an existing variable, while initialization creates a new variable and assigns a value to it.

• Initialization is done only once, while assignment can be done multiple times.

• Example of initialization: int x = 5; Example of assignment: x = 10;

• Initialization can also be done using constructors in object-oriented programming.

• In C++, uni...read more

Charging protocol in EVs and purpose of charging pin at inlet

• Charging protocol determines how the battery is charged and how much power is delivered

• Charging pin is used to connect the charging cable to the vehicle's charging inlet

• Charging protocols include AC charging, DC charging, and wireless charging

• Charging protocols also include different charging levels such as Level 1, Level 2, and Level 3

• Purpose of charging pin is to ensure safe and reliable transfer of power from the...read more

A normal function is called directly in the code, while a stored procedure is invoked using a database query.

• Normal function calling is done within the program code, while stored procedure invocation is done through a database query.

• Normal functions are defined and called within the same programming language, while stored procedures are defined and invoked within a database management system.

• Normal function calling is synchronous, while stored procedure invocation can be asyn...read more

Experience certainty refers to the level of confidence and assurance gained through repeated exposure to a particular task or situation.

• Experience certainty is achieved through repetition and familiarity.

• It allows individuals to perform tasks with greater ease and efficiency.

• For example, a pilot who has flown the same route multiple times will have a higher level of experience certainty compared to a pilot who is flying the route for the first time.

• Experience certainty can al...read more

The smallest real-time project in Java could be a simple chat application, while the biggest could be a complex financial trading system.

• Smallest real-time project in Java: Chat application

• Biggest real-time project in Java: Financial trading system

• Big Data refers to large and complex data sets that cannot be easily processed using traditional data processing applications.

• For performing actions on 2 billion entries, technologies like Hadoop, Spark, and languages like Java or S...read more

Firewall is a network security system that monitors and controls incoming and outgoing network traffic based on predetermined security rules.

• Firewall acts as a barrier between a trusted, secure internal network and another network, such as the Internet.

• It examines each packet of data that passes through it and determines whether to allow or block the traffic based on the set of rules.

• Firewalls can be hardware or software-based and can be configured to block specific types of ...read more

SDLC focuses on the development of software, while STLC focuses on the testing of software.

• SDLC involves planning, designing, coding, and deployment of software.

• STLC involves test planning, test case development, test execution, and defect tracking.

• SDLC is more focused on the overall software development process, while STLC is more focused on ensuring the quality of the software.

• SDLC is a broader process that includes STLC as one of its phases.

• Example: In SDLC, a software tea...read more

Stored procedures offer advantages such as improved performance, security, and code reusability.

• Stored procedures can reduce network traffic by executing multiple SQL statements at once.

• They can also improve performance by pre-compiling SQL statements.

• Stored procedures can enhance security by allowing access to only specific procedures rather than entire tables.

• They promote code reusability by allowing multiple applications to use the same stored procedure.

• Examples include pr...read more

PHP was chosen for its versatility, large community support, and ease of use.

• PHP is a widely used scripting language with a large community of developers and extensive documentation.

• It is known for its versatility and ability to integrate with various databases and web servers.

• PHP is also relatively easy to learn and has a low learning curve compared to other languages like JSP.

• While JSP may be considered more secure, PHP can still be used to build secure applications with pr...read more

File System in C++ is used for managing files and directories, providing functions for file input/output operations.

• C++ provides the library for file input/output operations.

• File streams can be used to read from and write to files.

• Common file operations include opening, closing, reading, and writing files.

• File streams can handle different file types such as text files and binary files.

• File system functions like file existence check, file deletion, and file renaming are avail...read more

A thread is a lightweight unit of execution within a process, while a process is an instance of a program in execution.

• A process has its own memory space, while threads share the same memory space within a process.

• Processes are independent and isolated from each other, while threads share resources and can communicate with each other more easily.

• Creating a new process is more resource-intensive than creating a new thread.

• Threads are scheduled by the operating system, while pr...read more

Python objects can be checked for their class using the type() function or the isinstance() function.

• Use the type() function to check the class of an object. For example, type(5) will return .

• Use the isinstance() function to check if an object belongs to a specific class. For example, isinstance(5, int) will return True.

• In Python, everything is an object, so you can check the class of any object using type() or isinstance().

Operating system is a software that manages computer hardware and software resources.

• Compiler translates high-level language code to machine code while interpreter executes code line by line.

• One byte is equal to 8 bits.

• Machine language is a low-level programming language consisting of binary code.

• Assembler converts assembly language code to machine code.

• Types of operating system include Windows, macOS, Linux, and Unix.

• Unix is a multi-user, multi-tasking operating system devel...read more

A basic program to control car temperature by turning on/off based on set limits.

• Create a variable to store current temperature

• Set a limit for turning on the temperature control

• Set a limit for turning off the temperature control

• Use conditional statements to check if temperature is above or below the limits

• Print 'Turn on' if temperature is above the limit, 'Turn off' if below

TestNG has 8 annotations including @Test, @BeforeSuite, @AfterSuite, @BeforeTest, @AfterTest, @BeforeClass, @AfterClass, @BeforeMethod, @AfterMethod.

• 1. @Test - Marks a method as a test method.

• 2. @BeforeSuite - Executed before the Test Suite.

• 3. @AfterSuite - Executed after the Test Suite.

• 4. @BeforeTest - Executed before the Test.

• 5. @AfterTest - Executed after the Test.

• 6. @BeforeClass - Executed before the first test method in the current class.

• 7. @AfterClass - Executed after a...read more

OOPs is a programming paradigm, Cloud Computing is a model for delivering IT services, Cyber Security is the practice of protecting computer systems, SQL is a language used to manage relational databases, DBMS is a software system used to manage databases, and a coding question is a problem-solving exercise.

• OOPs - Encapsulation, Inheritance, Polymorphism, Abstraction

• Cloud Computing - Infrastructure as a Service (IaaS), Platform as a Service (PaaS), Software as a Service (SaaS...read more

JSP is a Java-based technology used for creating dynamic web pages. It allows embedding Java code within HTML pages.

• JSP stands for JavaServer Pages.

• It is a technology used for developing web applications.

• JSP allows embedding Java code within HTML pages.

• It provides a simplified way to create dynamic web content.

• JSP files are compiled into servlets and executed on the server.

• Advantages of JSP include easy integration with Java code, reusable components, and separation of presen...read more

TCS bond agreement is a contract signed by employees to work for a certain period of time with the company.

• TCS bond agreement is a legal contract between TCS and its employees.

• Employees sign the bond agreement to work for a certain period of time with the company.

• The bond period can range from 1 to 2 years depending on the role and level of the employee.

• If an employee wishes to leave the company before the bond period ends, they are required to pay a certain amount as compens...read more

Selenium components include Selenium IDE, Selenium WebDriver, Selenium Grid, and Selenium RC.

• Selenium IDE: Record and playback tool for creating test scripts without programming.

• Selenium WebDriver: Automation tool for writing test scripts in various programming languages.

• Selenium Grid: Tool for running tests in parallel on multiple machines or browsers.

• Selenium RC (Remote Control): Deprecated tool for running tests in multiple browsers.

I would calmly acknowledge the bug, communicate the issue and steps being taken to resolve it, and work quickly to fix it without causing panic.

• Acknowledge the bug calmly and professionally

• Communicate the issue and steps being taken to resolve it

• Work quickly to fix the bug without causing panic

• Provide updates to the client on the progress

A program for creating a date selector from calendar.

• Create a calendar UI with selectable dates

• Implement logic to highlight selected date

• Add functionality to navigate between months and years

• Integrate with backend to fetch and display events on selected date

Stored procedures are pre-written SQL codes that can be saved and reused.

• Stored procedures can improve database performance by reducing network traffic.

• They can be used to enforce business rules and security measures.

• They can be parameterized to accept input values and return output values.

• Examples include procedures for inserting, updating, and deleting data.

• They can also be used for complex operations such as data aggregation and reporting.

Services and port numbers required to communicate desktop/laptop with MECM/SCCM deployment server.

• Services: SMS Agent Host, SMS Executive, SMS Site Component Manager

• Port numbers: 80 (HTTP), 443 (HTTPS), 10123 (Client notification)

• Firewall rules may need to be configured to allow communication

Middleware in Node.js is a function that sits between the server and the client and performs various tasks.

• Middleware functions can be used to handle requests, modify responses, and perform authentication and authorization.

• Examples of middleware in Node.js include body-parser, cookie-parser, and express-session.

• Middleware functions are executed in the order they are defined in the code.

• Middleware can be used to handle errors and pass them to the error handling middleware.

Control coupling and data coupling are two types of coupling in software engineering.

• Control coupling occurs when one module controls the flow of another module through parameters or flags.

• Data coupling occurs when two modules share data through parameters or global variables.

• Control coupling is considered more tightly coupled than data coupling.

• Examples of control coupling include passing a flag to a function to determine its behavior, or using a return value to control the ...read more

Functions return a value while stored procedures do not.

• Functions are used to perform a specific task and return a value to the caller.

• Stored procedures are used to execute a set of statements and do not return a value.

• Functions can be used in SELECT, WHERE, and HAVING clauses.

• Stored procedures can be used to modify data, but functions cannot.

• Functions can be called from within a stored procedure.

API configuration for frontend

• Define API endpoints and methods

• Ensure API responses are in the correct format for frontend

• Implement authentication and authorization

• Optimize API performance for frontend usage

• Document API usage for frontend developers

Page Object Model is a design pattern in test automation that represents web pages as objects, while Page Factory is a way to initialize elements in Page Object Model.

• Page Object Model is a design pattern used in test automation to represent web pages as objects

• It helps in creating reusable code and reduces code duplication

• Page Factory is a concept in Selenium WebDriver that helps in initializing elements in Page Object Model

• It uses @FindBy annotation to locate elements on a ...read more

Deadlocks occur when two or more processes are unable to proceed because each is waiting for the other to finish.

• Deadlocks happen when two or more processes are blocked and unable to proceed

• Each process is waiting for a resource that is being held by another process

• Deadlocks can be prevented by using techniques like resource allocation graphs and banker's algorithm

• Examples of deadlocks include the dining philosophers problem and the traffic deadlock problem

Types of file systems in OS include FAT, NTFS, HFS+, ext2/3/4, and APFS.

• FAT (File Allocation Table) is a simple file system used by older versions of Windows.

• NTFS (New Technology File System) is a more advanced file system used by newer versions of Windows.

• HFS+ (Hierarchical File System Plus) is used by Apple's macOS.

• ext2/3/4 are file systems used by Linux.

• APFS (Apple File System) is a newer file system used by Apple's macOS and iOS devices.

Routers connect networks while firewalls protect networks from unauthorized access.

• Routers direct traffic between networks while firewalls filter traffic based on predefined rules.

• Routers operate at layer 3 of the OSI model while firewalls operate at layer 4 or higher.

• Examples of routers include Cisco routers, while examples of firewalls include Fortinet firewalls.

• Routers can be used to segment networks while firewalls can be used to block malicious traffic.

• Routers are essent...read more

Cloud is a technology that allows users to access data and applications over the internet.

• Cloud computing is a model for delivering on-demand computing resources over the internet.

• It includes services like Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS).

• Cloud technology allows for scalability, flexibility, and cost savings compared to traditional on-premise solutions.

• Examples of cloud providers include Amazon Web Services (AW...read more

Linked Lists are a data structure used to store a collection of elements in a linear order.

• Each element in a linked list is called a node and contains a value and a reference to the next node.

• Linked lists can be singly linked (each node only has a reference to the next node) or doubly linked (each node has a reference to both the next and previous nodes).

• Insertion and deletion operations are efficient in linked lists, but accessing elements by index is not.

• Examples of applica...read more

Python is a high-level, interpreted programming language used for web development, data analysis, and artificial intelligence.

• Python is easy to learn and has a simple syntax.

• It has a large standard library with many pre-built modules.

• Python is used for web development with frameworks like Django and Flask.

• It is also used for data analysis with libraries like NumPy and Pandas.

• Python is case sensitive.

• It is a popular language for artificial intelligence and machine learning.

• Pyt...read more

Routing protocols are used to determine the best path for data to travel in a network.

• Distance Vector protocols: RIP, IGRP, EIGRP

• Link State protocols: OSPF, IS-IS

• Hybrid protocols: BGP

• Path Vector protocols: BGP

• IGP vs EGP

Yes, I am willing to learn coding if it is needed.

• I have some basic knowledge of coding and am willing to improve my skills.

• I am a quick learner and can adapt to new technologies easily.

• I am open to taking courses or attending training sessions to improve my coding skills.

• Learning coding will also help me better understand the systems I work with.

• For example, I have experience with Python and SQL, and can learn other languages as needed.

Smoke testing is a preliminary test to check if the software build is stable, while sanity testing is a subset of regression testing to verify specific functionality.

• Smoke testing is done to ensure the critical functionalities of the software are working fine after a build, while sanity testing is done to verify specific changes or fixes.

• Smoke testing is a shallow and wide approach to testing, covering all major areas of the software, while sanity testing is a focused and nar...read more

Retesting focuses on testing the same functionality again, while regression testing focuses on testing the impact of changes on existing functionalities.

• Retesting is done to ensure that a specific bug or issue has been fixed properly.

• Regression testing is done to ensure that new code changes have not adversely affected existing functionalities.

• Retesting is usually performed by the same tester who found the bug, while regression testing can be performed by any tester.

• Examples:...read more

Some popular tools for automation testing include Selenium, Appium, JUnit, TestNG, and Cucumber.

• Selenium: widely used for web application testing

• Appium: for mobile application testing

• JUnit: for unit testing in Java

• TestNG: for testing in Java

• Cucumber: for behavior-driven development testing

Constructor is a special method used to initialize objects in a class.

• Constructors have the same name as the class they belong to.

• They are called automatically when an object is created.

• They can take parameters to initialize the object's properties.

• They do not have a return type.

• Multiple constructors can be defined with different parameters.

• Example: public class Car { public Car(String make, String model) { ... } }

Code to allocate memory to an object

• Use the 'new' keyword in C++ to allocate memory to an object

• Use 'malloc' function in C to allocate memory to an object

• In Java, memory is automatically allocated to an object using 'new' keyword

• In Python, memory is automatically allocated to an object when it is created

Controls in UI are interactive elements that allow users to input data or interact with the application.

• Controls include buttons, input fields, checkboxes, dropdowns, sliders, etc.

• In Angular, controls are designed using directives like ngModel, ngForm, ngIf, ngFor, etc.

• In React, controls are created as components with state and props to manage user input.

• In Vue, controls are defined in the template using v-model, v-bind, v-on directives.

OOP stands for Object-Oriented Programming. Python and C differ in syntax, memory management, and application areas. A program to reverse a string can be written using loops or slicing.

• OOP is a programming paradigm that focuses on objects and their interactions.

• Python is a high-level language with dynamic typing and automatic memory management, while C is a low-level language with static typing and manual memory management.

• To reverse a string using loops, iterate through the ...read more

Yes, I have experience working with coding languages such as Python, Java, and C++.

• Experience with Python, Java, and C++

• Developed scripts and applications using these languages

• Familiar with object-oriented programming concepts

R, L, and C are basic electronic components used in circuits for resistance, inductance, and capacitance respectively.

• Resistors (R) limit current flow and reduce voltage

• Inductors (L) store energy in a magnetic field and resist changes in current

• Capacitors (C) store energy in an electric field and pass AC signals while blocking DC signals

• These components are used in various circuits such as filters, oscillators, and amplifiers

Paging is a memory management technique used by operating systems to manage memory usage.

• Paging divides memory into fixed-size pages.

• Pages are stored in physical memory or on disk.

• When a process needs a page, it is loaded into physical memory.

• If there is no space in physical memory, a page is swapped out to disk.

• Paging allows for efficient use of memory and prevents processes from accessing memory they shouldn't.

• Examples of operating systems that use paging include Windows, L...read more

To troubleshoot failed Windows server patches, check event logs, run Windows Update troubleshooter, verify system requirements, and manually install patches.

• Check event logs for error codes and details

• Run Windows Update troubleshooter to identify and fix issues

• Verify system requirements for the patches

• Manually download and install the failed patches

I will provide alternative solutions and resources to the user.

• Listen to the user's problem and understand their needs.

• Offer alternative solutions that may be within my scope of knowledge.

• Provide resources or refer the user to someone who can assist them.

• Follow up with the user to ensure their issue has been resolved.

You can check if two numbers are equal without using equality operator by using bitwise XOR operation.

• Use bitwise XOR operation on the two numbers. If the result is 0, then the numbers are equal.

• Example: Check if 5 and 5 are equal - 5 ^ 5 = 0

• Example: Check if 5 and 6 are equal - 5 ^ 6 = 3

BGP attributes are used to determine the best path for routing traffic between networks.

• BGP attributes include: AS Path, Next Hop, Local Preference, MED, Origin, and Community

• AS Path is a list of autonomous systems that the route has passed through

• Next Hop is the IP address of the next router on the path

• Local Preference is used to indicate the preferred path for outbound traffic

• MED (Multi-Exit Discriminator) is used to indicate the preferred path for inbound traffic

• Origin ind...read more

Pointers are variables that store the memory address of another variable. Datatypes are the types of data that can be stored in a variable.

• Pointers allow for dynamic memory allocation and manipulation.

• They are commonly used in programming languages like C and C++.

• Examples of pointers include int*, char*, and void*.

• Datatypes include integers, floating-point numbers, characters, and arrays.

• Sorting in descending order involves arranging elements from highest to lowest value.

Plant determination in SO is based on OTC process, contract vs scheduling agreement, third party process, consignment process, pricing, determinations, and IDOCs.

• Plant determination in Sales Order (SO) is determined based on the Order to Cash (OTC) process.

• In SAP, the plant is determined based on various factors such as the sales organization, distribution channel, and division.

• For example, if a company has multiple plants and warehouses, the system will determine the plant b...read more

Webdriver can be written in code using Selenium WebDriver library for automating web applications.

• Import the necessary Selenium WebDriver library in your code

• Create a WebDriver instance for the desired browser (e.g. Chrome, Firefox)

• Use WebDriver methods to interact with elements on the web page (e.g. findElement, click, sendKeys)

• Write test cases using WebDriver commands to automate testing scenarios

A view is a virtual table created by a query. Different types of views include materialized views, indexed views, and partitioned views.

• A view is a saved SQL query that acts as a virtual table

• Materialized views store the result set physically in the database

• Indexed views have indexes to improve query performance

• Partitioned views divide data into separate tables based on a criteria

SQL databases are relational and use structured query language, while NoSQL databases are non-relational and use various data models.

• SQL databases are based on a fixed schema, while NoSQL databases are schema-less.

• SQL databases use tables to store data, while NoSQL databases use various data models like key-value, document, columnar, or graph.

• SQL databases are better suited for complex queries and structured data, while NoSQL databases are more flexible and scalable for unstr...read more

Potential difference is the difference in electric potential between two points in an electric field.

• Potential difference is measured in volts (V)

• It is the work done per unit charge to move a charge from one point to another

• It is the driving force that causes current to flow in a circuit

• Potential difference can be calculated using Ohm's law: V = IR

• A battery creates a potential difference between its terminals to power a circuit

Supervised learning uses labeled data for training, while unsupervised learning uses unlabeled data.

• Supervised learning requires labeled data for training, while unsupervised learning does not.

• In supervised learning, the model learns from input-output pairs, while in unsupervised learning, the model finds patterns in the data.

• Examples of supervised learning include classification and regression tasks, while examples of unsupervised learning include clustering and dimensionali...read more

The parent class of all classes in Java is the Object class.

• All classes in Java implicitly extend the Object class.

• The Object class provides basic methods such as toString(), equals(), and hashCode().

• Any class can override these methods to provide custom implementations.

• Example: public class MyClass extends Object { ... }

• Example: Object obj = new MyClass();

OOPS (Object-Oriented Programming) is a programming paradigm based on the concept of objects, which can contain data and code.

• OOPS focuses on creating reusable code and organizing it into classes and objects.

• Examples of OOPS concepts include inheritance, polymorphism, encapsulation, and abstraction.

• Inheritance allows a class to inherit properties and behavior from another class.

• Polymorphism allows objects of different classes to be treated as objects of a common superclass.

• En...read more

Python is a versatile language with a simple syntax and vast libraries. It's easy to learn and widely used in data science and web development.

• Python has a simple and readable syntax, making it easy to learn and write code quickly.

• Python has a vast collection of libraries and frameworks for various purposes, such as data science, web development, and machine learning.

• Python is an interpreted language, which means it doesn't need to be compiled before running, making it faster...read more

Inverter converts DC to AC. Motor control involves adjusting frequency and voltage of AC to control motor speed.

• Inverter uses power electronics to convert DC to AC

• Motor control involves adjusting frequency and voltage of AC to control motor speed

• Frequency and voltage are adjusted using pulse width modulation (PWM)

• Motor speed can be controlled by adjusting the duty cycle of PWM signal

• Examples of motor control techniques include scalar control and vector control

Explanation of various networking terms and protocols.

• AD - Active Directory is a directory service that stores information about objects on a network.

• DNS - Domain Name System is a hierarchical naming system that translates domain names to IP addresses.

• DHCP - Dynamic Host Configuration Protocol is a network protocol that automatically assigns IP addresses to devices.

• IP Classes - IP addresses are divided into classes based on the number of bits used for the network and host por...read more

REPL in Node.js stands for Read-Eval-Print Loop, allowing users to interactively run JavaScript code.

• REPL is a command-line tool that takes in user input, evaluates it, and returns the result.

• It is useful for testing small code snippets, debugging, and experimenting with Node.js features.

• Example: Typing '2 + 2' in the Node.js REPL will return '4'.

A switch is a networking device that connects devices together on a local area network (LAN) and forwards data packets between them.

• Switches operate at the data link layer of the OSI model.

• They use MAC addresses to forward data to the correct destination.

• Switches can improve network performance by reducing network congestion and collisions.

• Examples of switches include Ethernet switches, LAN switches, and network switches.

Code to generate Fibonacci series

• Declare variables for first two numbers in the series

• Loop through the series and add the previous two numbers to get the next number

• Print the series

Yes, I have worked on a project where I developed a web application using Java programming language.

• Developed a web application using Java programming language

• Implemented various features and functionalities

• Collaborated with a team of developers to ensure project success

A basic code to find prime numbers in a given range

• Iterate through numbers in the given range

• Check if each number is divisible by any number other than 1 and itself

• If not divisible, then it is a prime number