10+ Capacit'e Infraprojects Interview Questions and Answers

React Native, GraphQL, Docker

• Learned React Native for cross-platform mobile app development

• Explored GraphQL for efficient data fetching and manipulation

• Gained knowledge in Docker for containerization and deployment

Implement a code scenario using design patterns

• Identify the problem statement and requirements

• Choose appropriate design patterns like Singleton, Factory, Observer, etc.

• Implement the code following the selected design patterns

• Test the code for functionality and efficiency

Default and static methods in interface allow for method implementation and utility methods in Java interfaces.

• Default methods provide a default implementation for a method in an interface.

• Static methods in interfaces can be called directly on the interface itself.

• Default and static methods were introduced in Java 8.

• Default methods can be overridden by implementing classes.

• Static methods cannot be overridden and are not inherited by implementing classes.

There are multiple types of authentication that can be implemented, including password-based, token-based, biometric, and multi-factor authentication.

• Password-based authentication: Users authenticate themselves using a password.

• Token-based authentication: Users authenticate themselves using a token, such as a one-time password or a security key.

• Biometric authentication: Users authenticate themselves using their unique biological characteristics, such as fingerprints or facial...read more

Design a database scheme for Amazon website

• Create tables for users, products, orders, reviews, and payments

• Use primary and foreign keys to establish relationships between tables

• Include attributes such as user_id, product_id, order_id, review_id, and payment_id

• Implement indexes for faster data retrieval

• Consider denormalization for performance optimization

The question asks to find the number of consecutive alphabets in a string.

• Iterate through the string and check if each character is consecutive to the previous one.

• Keep track of the count of consecutive alphabets encountered.

• Return the count at the end.

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

• Use lazy initialization to create the instance only when needed.

• Use synchronized keyword to make the getInstance() method thread-safe.

• Consider using double-checked locking for better performance.

• Use enum to implement singleton pattern as it is inherently thread-safe.

API endpoint to update employee salary

• Create a PUT request endpoint with employee ID and new salary as parameters

• Verify user authentication and authorization before updating the salary

• Update the salary in the database and return success message

Develop a Spring Boot API for a given table

• Create a Spring Boot project with necessary dependencies

• Define entity class representing the table

• Create a repository interface extending JpaRepository

• Implement service layer with business logic

• Create REST controller with CRUD operations

Linked list is a data structure where each element points to the next element in the sequence.

• Nodes contain data and a reference to the next node

• Insertion and deletion can be done efficiently in a linked list

• Traversal starts from the head node and follows the next pointers

Height of a binary tree is the maximum number of edges on the longest path from the root node to a leaf node.

• The height of an empty tree is -1.

• The height of a tree with only one node is 0.

• The height of a binary tree can be calculated recursively by finding the height of the left and right subtrees and adding 1 to the maximum of the two heights.

Caching in Hibernate improves performance by storing frequently accessed data in memory.

• Hibernate supports first-level cache at session level

• Second-level cache can be configured at session factory level

• Caching strategies include read-only, read-write, and transactional

• Cache providers like Ehcache, Infinispan, and Hazelcast can be used

Sort an array of 0s and 1s in linear time complexity.

• Use two pointers approach - one from the start and one from the end of the array.

• Swap 0s to the left side and 1s to the right side until the pointers meet.

• Time complexity: O(n), Space complexity: O(1)

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

• Use a combination of a doubly linked list and a hashmap to efficiently implement LRU cache.

• Keep track of the most recently used item at the head of the linked list and the least recently used item at the tail.

• When a new item is accessed, move it to the head of the linked list and update the hashmap accordingly.

• If the cache is full, remove the item at the ...read more