Infosys Senior Software Engineer Interview Questions and Answers

Polymorphism is the ability of a single function or method to operate on different types of data.

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

• There are two types of polymorphism: compile-time (method overloading) and runtime (method overriding).

• Example: Inheritance in object-oriented programming languages like Java allows for polymorphism.

Abstract class can have both abstract and non-abstract methods, while interface can only have abstract methods.

• Abstract class can have constructors, fields, and methods, while interface cannot have any implementation.

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

• Abstract classes are used to define a common behavior for subclasses, while interfaces are used to define a contr...read more

Middleware in .NET Core is software components that are assembled into the pipeline to handle requests and responses.

• Middleware components are executed in the order they are added to the pipeline.

• They can perform tasks such as authentication, logging, error handling, etc.

• Examples of middleware in .NET Core include UseAuthentication, UseMvc, UseStaticFiles, etc.

Query to find 2nd highest salary in a table

• Use a subquery to select distinct salaries

• Order the salaries in descending order

• Use LIMIT to get the second highest salary

final, finally, and finalize are related to Java programming language.

• final is a keyword used to restrict the user from changing the value of a variable.

• finally is a block of code that is always executed, whether an exception is thrown or not.

• finalize is a method used for cleanup operations before an object is garbage collected.

Annotation used to mark a class as a Spring Boot application.

• Used to indicate the main class of a Spring Boot application

• Enables auto-configuration and component scanning

• Can be used with additional annotations like @SpringBootApplication

JVM is the Java Virtual Machine that executes Java bytecode. JRE is the Java Runtime Environment that includes JVM and libraries. JDK is the Java Development Kit that includes JRE and development tools.

• JVM is responsible for running Java programs by interpreting bytecode.

• JRE includes JVM along with libraries and other components needed to run Java applications.

• JDK is a full-featured development kit that includes J...read more

Object-oriented programming paradigm focusing on objects and classes for code organization and reusability.

• Encapsulation: Bundling data and methods that operate on the data into a single unit (class).

• Inheritance: Ability of a class to inherit properties and behavior from another class.

• Polymorphism: Ability to present the same interface for different data types.

• Abstraction: Hiding the complex implementation details...read more