200+ Senior Software Engineer 2 Interview Questions and Answers

Use compensating transactions and distributed tracing for managing transaction and logging in case of service B failure.

• Implement compensating transactions to rollback changes made by service B in case of failure.

• Use distributed tracing to track the flow of requests and identify where the failure occurred.

• Implement retry mechanisms to handle transient failures in service B.

• Use circuit breakers to prevent cascading failures in the system.

• Implement centralized logging to captur...read more

Design a system diagram for a scalable e-commerce platform with user management and payment processing.

• Use microservices architecture for scalability and maintainability.

• Implement a user management service for authentication and authorization.

• Integrate a payment gateway service for secure transactions (e.g., Stripe, PayPal).

• Utilize a database service for storing user data and transaction history.

• Incorporate a caching layer (e.g., Redis) to improve performance.

• Deploy services ...read more

System diagram for e-commerce order placement and history retrieval

• Frontend: Customer interface for browsing products, adding to cart, and placing orders

• Backend: Order processing system to handle order placement, payment processing, and order fulfillment

• Database: Store customer information, order details, and order history for retrieval

• APIs: Communication between frontend, backend, and database for seamless order processing

• Analytics: Track order history and customer behavior ...read more

Java 8 features like lambda expressions and functional interfaces make coding with streams easier and more efficient.

• Lambda expressions allow for concise and readable code when working with streams.

• Functional interfaces like Predicate, Function, and Consumer can be used with streams to perform operations on elements.

• Stream API provides methods like map, filter, and reduce for processing collections of data in a declarative way.

• Parallel streams enable concurrent processing of ...read more

HashMap internally uses an array of linked lists to store key-value pairs. To store duplicate keys, we can use a custom implementation of HashMap.

• HashMap internally uses an array of linked lists to handle collisions.

• To store duplicate keys, we can create a custom HashMap implementation that allows multiple values for the same key.

• One approach is to use a HashMap with values as lists, where each key can have multiple values associated with it.

Isolation levels in transactions determine the degree to which transactions are isolated from each other. Propagation types define how transactions are propagated between different components.

• Isolation levels include READ UNCOMMITTED, READ COMMITTED, REPEATABLE READ, and SERIALIZABLE.

• Propagation types include REQUIRED, REQUIRES_NEW, SUPPORTS, MANDATORY, and NEVER.

• Isolation levels control the visibility of changes made by other transactions before the current transaction is co...read more

The @Service annotation is used in Spring framework to indicate that a class is a service component.

• Used to mark a class as a service component in Spring framework

• Helps in auto-detection and auto-configuration of Spring beans

• Facilitates dependency injection and inversion of control

Program to convert integer to Excel column name, find first non-repeating character in a string, and create a map of last names with count of names.

• For converting integer to Excel column name, you can use a recursive function to map the remainder of the division by 26 to the corresponding letter.

• To find the first non-repeating character in a string, you can iterate through the string and use a HashMap to store the count of each character.

• For creating a map of last names with ...read more

As a full stack developer with MSBI, I leverage data integration and analytics to build robust applications across the stack.

• Data Integration: I utilize SQL Server Integration Services (SSIS) for ETL processes, ensuring seamless data flow between systems.

• Data Analysis: Using SQL Server Analysis Services (SSAS), I create multidimensional models for complex data analysis, enhancing decision-making.

• Reporting: I implement SQL Server Reporting Services (SSRS) to generate interacti...read more

Pseudo code to sort a random list of numbers in ascending order

• Loop through the list and compare adjacent elements

• If the left element is greater than the right element, swap them

• Repeat until no swaps are needed

Implement LRU cache with expiration, priority, and recentness based eviction policy.

• Use a doubly linked list to keep track of the order of elements based on recentness.

• Use a hashmap to store key-value pairs for quick access.

• Implement a priority queue to handle eviction based on priority.

• Set expiration time for each element and remove expired elements during access or eviction.

Python's GIL limits true parallelism in multi-threading, causing threads to execute sequentially rather than concurrently.

• The Global Interpreter Lock (GIL) allows only one thread to execute Python bytecode at a time.

• This means that CPU-bound threads cannot run in parallel, leading to performance bottlenecks.

• I/O-bound threads can benefit from multi-threading, as they can release the GIL while waiting for I/O operations.

• Example: In a web scraping application, multiple threads c...read more

Design a parking lot system with features like ticketing, payment, and space availability tracking.

• Create a class for ParkingLot with attributes like total number of spaces, available spaces, and ticketing system.

• Implement methods for issuing tickets, calculating parking fees, and updating space availability.

• Consider implementing a payment system for customers to pay for parking.

• Include features like tracking available spaces, handling multiple levels or sections in the parki...read more

Find the number of days until a warmer temperature for each day in a list of daily temperatures.

• Use a stack to keep track of indices of temperatures.

• Iterate through the temperature array from left to right.

• For each temperature, pop from the stack until the current temperature is warmer.

• The difference in indices gives the number of days until a warmer temperature.

• Example: For temperatures [73, 74, 75, 71, 69, 72, 76, 73], the output is [1, 1, 4, 2, 1, 1, 0, 0].

Multiple inheritance is a feature in object-oriented programming where a class can inherit attributes and methods from more than one parent class.

• Allows a class to inherit from multiple parent classes, combining their attributes and methods

• Can lead to the diamond problem where ambiguity arises if two parent classes have a method with the same name

• Achieved in languages like C++ using virtual inheritance or interfaces in languages like Java

Response status codes indicate the outcome of an HTTP request, customizable to meet specific business needs.

• 200 OK: Standard response for successful requests.

• 201 Created: Used when a new resource is created, e.g., after a POST request.

• 400 Bad Request: Indicates that the server cannot process the request due to client error.

• 401 Unauthorized: Indicates that authentication is required and has failed or not been provided.

• 404 Not Found: Used when the requested resource could not b...read more

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

• Singleton pattern can be implemented by making the constructor private and providing a static method to access the instance.

• The pattern can be broken by using reflection to access the private constructor and create multiple instances.

• Another way to break the Singleton pattern is by using multiple class loaders in Java.

• Thread synchronization issues can also lead to breaking the ...read more

Led a successful migration of a legacy system to a cloud-based architecture, enhancing performance and scalability.

• Conducted a thorough assessment of the existing legacy system to identify dependencies and potential challenges.

• Developed a detailed migration plan, including timelines, resource allocation, and risk management strategies.

• Utilized AWS services to migrate databases, ensuring data integrity and minimal downtime during the transition.

• Implemented automated testing to...read more

Create a Shell script to add 100 users on 5 different servers.

• Use a loop to create 100 users on each server.

• Utilize the 'useradd' command to add users.

• Ensure unique usernames for each user on each server.

• Consider using SSH for remote server access.

• Test the script on a single server before running on all servers.

I possess strong skills in advanced database queries and performance optimization, ensuring efficient data retrieval and management.

• Proficient in writing complex SQL queries, including JOINs, subqueries, and CTEs for data aggregation.

• Experience with indexing strategies to improve query performance, such as creating composite indexes for multi-column searches.

• Utilized query optimization techniques like EXPLAIN plans to analyze and refine slow-running queries.

• Implemented cachin...read more

I utilized various technologies to solve complex problems in software development, enhancing performance and user experience.

• Microservices Architecture: Implemented a microservices architecture using Spring Boot, which improved scalability and allowed independent deployment of services.

• Database Optimization: Resolved performance issues by optimizing SQL queries and implementing indexing strategies in PostgreSQL, reducing query time by 40%.

• API Development: Developed RESTful AP...read more

Inter-service communication in microservices involves using protocols like HTTP, gRPC, or messaging queues.

• Microservices communicate with each other through APIs using protocols like HTTP or gRPC.

• Message queues like RabbitMQ or Kafka can be used for asynchronous communication between services.

• Service discovery tools like Consul or Eureka help services locate each other dynamically.

• API gateways can be used to manage and secure communication between services.

• Event-driven archit...read more

Design patterns in microservice architecture help in solving common design problems and improving scalability, maintainability, and flexibility.

• Service Registry pattern - used for service discovery and registration

• Circuit Breaker pattern - used for fault tolerance and resilience

• API Gateway pattern - used for routing and load balancing

• Saga pattern - used for managing distributed transactions

• Event Sourcing pattern - used for capturing all changes to an application state as a se...read more

Types of dependency injection include constructor injection, setter injection, and interface injection.

• Constructor injection: Dependencies are provided through a class's constructor.

• Setter injection: Dependencies are provided through setter methods.

• Interface injection: Dependencies are provided through an interface method.

RestTemplate is a synchronous client for making HTTP requests, while Feign Client is a declarative HTTP client that simplifies making API calls.

• RestTemplate is part of the Spring framework and requires manual configuration for each request.

• Feign Client is a declarative client that uses annotations to define API endpoints and parameters.

• RestTemplate is synchronous, blocking the calling thread until the response is received.

• Feign Client is asynchronous by default, allowing for ...read more

Transaction management in Spring Boot ensures data integrity by managing database transactions.

• Spring Boot uses @Transactional annotation to manage transactions

• It ensures that all operations within a transaction are completed successfully or rolled back if an error occurs

• Transactions can be managed programmatically using TransactionTemplate

• Supports different transaction isolation levels like READ_COMMITTED, REPEATABLE_READ, etc.

Design a system to handle 10 lacs transactions per second.

• Use distributed systems and load balancing to handle the high volume of transactions.

• Implement caching mechanisms to reduce database load.

• Use high-performance hardware and optimize code for speed.

• Consider using a NoSQL database for faster read/write operations.

• Implement fault-tolerant mechanisms to ensure system reliability.

• Use asynchronous processing to handle requests quickly.

• Consider using a message queue to handle ...read more