20+ CitiusTech Senior Software Engineer Interview Questions and Answers

No, assigning null to an array makes it empty and its length becomes 0.

• Assigning null to an array makes it empty.

• The length of an empty array is 0.

• Trying to access length property of null will result in an error.

Manual testing is the process of manually testing software for defects, functionality, and usability.

• Manual testing involves testers executing test cases without the use of automation tools.

• It is a time-consuming process but allows for thorough testing of software.

• Testers document their findings and report any issues to the development team for resolution.

Answers to SQL-related questions for Senior Software Engineer position

• To see SQL sessions, use the sp_who2 stored procedure or the Activity Monitor in SQL Server Management Studio

• To store temporary data inside a stored procedure, use table variables or temporary tables

• Use temp tables when you need to store large amounts of data or when you need to perform complex joins or aggregations

• Index seek is a type of index access method that uses a seek operation to find the data, whil...read more

Reverse a given string and sort an array of strings.

• To reverse a string, iterate through the characters in reverse order and append them to a new string.

• To sort an array of strings, use Arrays.sort() method in Java.

• Example: String str = "hello"; String reversed = ""; for(int i=str.length()-1; i>=0; i--) { reversed += str.charAt(i); }

• Example: String[] arr = {"banana", "apple", "orange"}; Arrays.sort(arr);

Authentication in .NET involves using various authentication mechanisms such as Forms Authentication, Windows Authentication, and OAuth.

• Use Forms Authentication for web applications

• Use Windows Authentication for intranet applications

• Use OAuth for third-party authentication

• Implement authentication using ASP.NET Identity

• Use secure password storage mechanisms such as hashing and salting

A pipe is a feature in Angular that allows you to transform data before displaying it.

• Pipes are used in Angular templates with the '|' symbol.

• There are built-in pipes like 'uppercase' and 'date'.

• Custom pipes can be created using the 'Pipe' decorator and implementing the 'PipeTransform' interface.

• Custom pipes can take arguments to modify their behavior.

• Pipes can be chained together to perform multiple transformations on data.

SOLID principles are a set of five design principles in object-oriented programming to make software designs more understandable, flexible, and maintainable.

• Single Responsibility Principle (SRP) - A class should have only one reason to change.

• Open/Closed Principle (OCP) - Software entities should be open for extension but closed for modification.

• Liskov Substitution Principle (LSP) - Objects of a superclass should be replaceable with objects of its subclasses without affecting...read more

Null value in JavaScript represents absence of any object value.

• Null is a primitive value in JavaScript.

• It is assigned to a variable to indicate that it has no value.

• It is different from undefined, which means a variable has been declared but not assigned a value.

• Null is falsy in JavaScript, meaning it is considered false in a boolean context.

• Null can be used to clear the value of an object property.

A hashmap is a data structure that stores key-value pairs and uses a hash function to map keys to their corresponding values.

• Hashmap uses a hash function to determine the index of the key-value pair in the underlying array.

• Collisions can occur when two keys hash to the same index, which is resolved using techniques like chaining or open addressing.

• Hashmap typically has an underlying array where each element is a linked list of key-value pairs with the same hash value.

• Retrievi...read more

I have worked with design patterns such as Singleton, Factory, Observer, and Strategy.

• Singleton pattern ensures a class has only one instance and provides a global point of access to it.

• Factory pattern creates objects without specifying the exact class of object that will be created.

• Observer pattern defines a one-to-many dependency between objects so that when one object changes state, all its dependents are notified and updated automatically.

• Strategy pattern defines a family...read more

messageID is a unique identifier assigned to each HL7 message.

• messageID is typically found in the MSH segment of an HL7 message.

• It is used to uniquely identify each message within a system or network.

• messageID can be alphanumeric and is often generated by the sending system.

• It helps in tracking and managing messages in a healthcare environment.

I have worked on various message types including JSON, XML, SOAP, and REST.

• JSON - Used for data interchange between systems.

• XML - Used for defining document structures.

• SOAP - Used for communication between applications.

• REST - Used for building APIs and web services.

Junit test cases should always be re-run to ensure code quality and prevent regression.

• Junit test cases should be run after every code change.

• Test cases should cover all possible scenarios and edge cases.

• Test cases should be automated to save time and ensure consistency.

• Test cases should be reviewed and updated regularly.

• Regression testing should be performed to ensure new changes do not break existing functionality.

Dependency injection is a design pattern where an object's dependencies are provided externally rather than created internally.

• Dependency injection helps to decouple components and make them more modular.

• It allows for easier testing and maintenance of code.

• There are three types of dependency injection: constructor injection, setter injection, and interface injection.

• Example: Instead of creating a database connection object within a class, the object is passed in as a paramete...read more

LRU cache is a data structure that stores the most recently used items and removes the least recently used items when full.

• Use a doubly linked list to keep track of the order of items based on their usage.

• Use a hashmap to quickly access items in the cache.

• When an item is accessed, move it to the front of the linked list to mark it as the most recently used.

let, var and const are used to declare variables in JavaScript with different scoping rules and mutability.

• let and var are used to declare variables that can be reassigned later, but var has function scope while let has block scope.

• const is used to declare variables that cannot be reassigned and have block scope.

• Using const does not mean the value is immutable, only the variable reference is.

• let and const were introduced in ES6 while var has been around since the beginning of...read more

Design patterns are reusable solutions to common problems in software design.

• Design patterns help in creating maintainable and scalable code.

• Examples include Singleton, Factory, Observer, and Strategy patterns.

• Singleton pattern ensures a class has only one instance.

• Factory pattern creates objects without specifying the exact class.

• Observer pattern defines a one-to-many dependency between objects.

• Strategy pattern defines a family of algorithms and encapsulates each one.

• Underst...read more

Middleware is software that acts as a bridge between different applications, allowing them to communicate and exchange data.

• Middleware is a layer of software that sits between applications and operating systems

• It provides services such as message routing, authentication, and data transformation

• Examples include Apache Tomcat, Microsoft IIS, and IBM WebSphere

Radiology workflow involves the process of imaging, interpreting, and reporting on medical images.

• Patient arrives for imaging appointment

• Technologist performs imaging procedure (X-ray, MRI, CT scan, etc.)

• Images are sent to radiologist for interpretation

• Radiologist analyzes images and generates report

• Report is sent to referring physician for further action

Event loop is a mechanism that allows non-blocking I/O operations in a single-threaded environment.

• Event loop is used in programming languages like JavaScript and Python.

• It manages the execution of multiple tasks by prioritizing them based on their priority level.

• It continuously checks for new events and executes them in a loop.

• It allows for efficient handling of I/O operations without blocking the main thread.

• It is commonly used in web development for handling client-server ...read more

Use a subquery to find the second highest salary in a table.

• Use a subquery to select the maximum salary from the table.

• Then use another subquery to select the maximum salary that is less than the maximum salary found in the first subquery.

React Native is a framework for building mobile applications using JavaScript and React.

• Allows developers to write code once and deploy it on both iOS and Android platforms

• Utilizes native components for better performance and user experience

• Supports hot reloading for faster development iterations

useEffect is a hook in React that allows functional components to perform side effects.

• useEffect is used to perform side effects in functional components

• It runs after every render by default

• It can be used to fetch data, subscribe to events, update the DOM, etc.

• It can take a second argument which is an array of dependencies to control when the effect runs

Abstract classes can have both abstract and non-abstract methods, while interfaces can only have abstract methods.

• Abstract classes can have constructors, fields, and non-abstract methods.

• Interfaces can only have abstract methods and constants.

• A class can implement multiple interfaces but can only inherit from one abstract class.