30+ Senior Software Development Engineer Interview Questions and Answers

Level order traversal of a binary search tree from leaf to root.

• Perform a level order traversal of the binary search tree

• Start from the leaf nodes and move towards the root

• Print the nodes in a single line or print a new line for every level

Answers to common technical questions related to Spring Boot, microservices, programming concepts, and sample program implementation.

• Spring Boot annotations include @RestController, @Service, @Component, @Autowired, @RequestMapping, etc.

• Microservice architecture is a design approach where an application is composed of small, independent services that communicate over HTTP/REST or messaging protocols.

• Call by value passes a copy of the variable's value to a function, while call...read more

You can reset the identity column using DBCC Checkident command.

• Use DBCC Checkident command with RESEED option to reset the identity column.

• Specify the table name and the new identity value as parameters.

• For example, to insert a new identity of 100 in a table named 'MyTable', use: DBCC Checkident('MyTable', RESEED, 100);

To remove the nth node from the end of a linked list, we can use a two-pointer approach.

• Use two pointers, one moving n steps ahead of the other

• When the first pointer reaches the end, the second pointer will be at the nth node from the end

• Adjust the pointers to remove the nth node

CLR stands for Common Language Runtime. Delegates are type-safe function pointers. SOLID principles are design principles for software development. OOP pillars are Abstraction, Encapsulation, Inheritance, Polymorphism.

• CLR is the runtime environment in which .NET applications run.

• Delegates are type-safe function pointers that allow methods to be passed as parameters.

• SOLID principles are Single Responsibility, Open/Closed, Liskov Substitution, Interface Segregation, Dependency ...read more

Use parallel processing and efficient data structures to dump large data efficiently.

• Utilize parallel processing to divide the data into smaller chunks and process them simultaneously.

• Implement efficient data structures like arrays, hashmaps, or trees to store and retrieve the data quickly.

• Optimize the code for memory usage and processing speed to handle large amounts of data efficiently.

Java 8 introduced several new features such as lambda expressions, streams, and functional interfaces.

• Lambda expressions allow for more concise code by enabling functional programming.

• Streams provide a way to work with collections in a more functional style, allowing for parallel processing and lazy evaluation.

• Functional interfaces are interfaces with a single abstract method, which can be implemented using lambda expressions.

• Other features include default methods in interfac...read more

Dependency injection is used to decouple components and improve testability, maintainability, and flexibility.

• Enables loose coupling between components

• Improves testability by allowing easy mocking and stubbing of dependencies

• Enhances maintainability by separating concerns and reducing code duplication

• Increases flexibility by enabling runtime configuration of dependencies

• Promotes modular and reusable code

• Facilitates easier unit testing and integration testing

Find duplicate elements from array

• Iterate through the array and use a hash set to keep track of seen elements

• If an element is already in the set, it is a duplicate

• Return the set of duplicate elements

DPDK core queue threads work by directly accessing NIC hardware queues for packet processing, bypassing the kernel for improved performance.

• DPDK core queue threads are used to handle packet processing in a multi-core environment.

• These threads directly access NIC hardware queues to receive and transmit packets.

• By bypassing the kernel, DPDK achieves lower latency and higher throughput for network applications.

• DPDK provides APIs for managing core queue threads and interacting wi...read more

Design a validator and write a running code within 30 mins

• Define the validation rules and criteria

• Implement the validation logic using a programming language of choice

• Test the validator with different input data to ensure accuracy

Sort an arraylist with java stream and functional interfaces

• Use the sorted() method of Stream to sort the arraylist

• Pass a Comparator to the sorted() method to define the sorting order

• Use lambda expressions or method references to define the Comparator

• Collect the sorted stream back into an ArrayList using the collect() method

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

• Encapsulation: Bundling data and methods that operate on the data within one unit (e.g., a class).

• Inheritance: Mechanism to create a new class using properties and methods of an existing class (e.g., a 'Dog' class inheriting from an 'Animal' class).

• Polymorphism: Ability to present the same interface for different underlying data types (e.g., a functi...read more

Convert an array of strings to a LinkedList

• Create a new LinkedList

• Iterate through the array and add each element to the LinkedList

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

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

• Interface can only have abstract methods and constants.

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

• Abstract classes are used to provide a common base for multiple classes, while interfaces define a contract that implementing classes must follow.

Design a transaction system Bank Wallet.

• Implement user authentication and authorization for secure transactions

• Allow users to deposit, withdraw, and transfer funds

• Provide transaction history and balance updates

• Implement security measures such as encryption and two-factor authentication

SQL is a programming language used for managing and manipulating relational databases.

• SQL stands for Structured Query Language.

• It is used to communicate with databases to retrieve, insert, update, and delete data.

• Common SQL commands include SELECT, INSERT, UPDATE, DELETE.

• SQL can be used to create and modify database schemas.

• Examples of popular database management systems that use SQL include MySQL, PostgreSQL, and Oracle.

I will explain my code and suggest improvements for better performance and readability.

• Start by providing an overview of the code structure and functionality.

• Explain the key algorithms and data structures used in the code.

• Discuss any potential bottlenecks or areas for optimization.

• Suggest improvements such as refactoring for better readability, optimizing algorithms, or implementing best practices.

• Provide examples of before and after code snippets to illustrate improvements.

chop and chomp are string manipulation functions in programming languages.

• chop removes the last character from a string

• chomp removes the newline character from the end of a string

• Both functions are commonly used in languages like Perl and Ruby

A cloud storage service like Google Drive for storing and sharing files

• Allow users to upload, store, and organize files in folders

• Provide sharing options for files and folders with permissions

• Include collaboration features like real-time editing and commenting

• Offer integration with other services like Google Docs, Sheets, and Slides

Designing a workflow engine involves creating a system to manage and execute a series of tasks in a specific order.

• Identify the different steps or tasks in the workflow

• Define the dependencies between tasks

• Implement logic for task execution and error handling

• Consider scalability and performance requirements

• Use a state machine or graph-based approach for modeling workflows

New syntaxes in SAP S4 HANA include CDS views, AMDP, and SQLScript enhancements.

• Core Data Services (CDS) views allow for defining data models and database views in a single language.

• ABAP Managed Database Procedures (AMDP) enable the execution of database procedures within ABAP code.

• SQLScript enhancements provide improved performance and flexibility for database operations.

A trigger write with logic explanation in software development.

• Triggers are database objects that are automatically executed or fired when certain events occur in a database.

• Triggers can be used to enforce business rules, validate input data, or maintain referential integrity.

• Example: A trigger can be set up to automatically update a 'last_modified' timestamp whenever a record is updated in a table.

Four OOP principles are encapsulation, inheritance, polymorphism, and abstraction.

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

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

• Polymorphism: Ability of different classes to be treated as instances of a common superclass.

• Abstraction: Hides the complex implementation details and only shows the necessary features of an object.

Web APIs are interfaces that allow different software applications to communicate with each other over the internet.

• Web APIs are used to define the methods for accessing specific functionality or data from a web server.

• They typically use HTTP requests to send and receive data.

• Examples of Web APIs include RESTful APIs, SOAP APIs, and GraphQL APIs.

• Web APIs are commonly used in web development to enable integration between different systems or services.

A bug is an error, flaw, failure, or fault in a computer program or system that causes it to produce incorrect or unexpected results.

• A bug can manifest as a software crash, incorrect output, or unexpected behavior.

• Bugs can be caused by coding errors, design flaws, or unexpected interactions between different components.

• Examples of bugs include logic errors, syntax errors, and memory leaks.

A dataset is a collection of data that is organized in a structured format for easy access and analysis.

• A dataset can consist of a single table or multiple tables of data.

• Each row in a dataset represents a unique record, while each column represents a specific attribute or variable.

• Datasets can be used for various purposes such as statistical analysis, machine learning, and data visualization.

Reflection is the ability of a program to inspect and modify its own structure and behavior at runtime.

• Allows inspection of classes, methods, and fields at runtime.

• Enables dynamic method invocation, e.g., calling a method by name.

• Facilitates the creation of frameworks and libraries, like dependency injection.

• Example in Java: Class.forName('ClassName') retrieves class metadata.

• Example in C#: typeof(ClassName) provides type information.

Microservices are a software development approach where applications are broken down into smaller, independent services that communicate with each other through APIs.

• Microservices allow for greater flexibility and scalability in software development.

• Each microservice is responsible for a specific function or feature of the application.

• Microservices can be developed, deployed, and scaled independently of each other.

• Examples of companies using microservices include Netflix, Ama...read more

To find the middle of a linked list, use the slow and fast pointer technique.

• Initialize two pointers, slow and fast, both pointing to the head of the linked list.

• Move the slow pointer by one step and the fast pointer by two steps until the fast pointer reaches the end of the list.

• The position of the slow pointer will be the middle of the linked list.

Java 8 introduced new features like lambda expressions, streams, and functional interfaces.

• Lambda expressions allow for more concise code and easier parallel programming.

• Streams provide a way to work with collections in a functional style.

• Functional interfaces can have only one abstract method and are used for lambda expressions.

• Optional class helps to avoid NullPointerExceptions.

• Default methods allow interfaces to have method implementations.

• Method references provide a way t...read more

Spring is a powerful and lightweight framework for building Java applications.

• Spring provides comprehensive infrastructure support for developing Java applications.

• It promotes good design practices such as dependency injection and aspect-oriented programming.

• Spring Boot simplifies the setup and configuration of Spring applications.

• Spring MVC is a popular module for building web applications.

• Spring Data JPA simplifies data access with JPA.

• Spring Security provides authenticatio...read more