10+ Consolidated Coin Company Interview Questions and Answers

Design a layered architecture for saving user data to db with appropriate annotations.

• Create a data access layer (DAO) to interact with the database using annotations like @Repository

• Implement a service layer to handle business logic with annotations like @Service

• Use @Entity annotation on model classes to map them to database tables

• Add @Id annotation on primary key fields in model classes

• Utilize @Transactional annotation on service methods for transaction management

SQL query to find nth highest salary using LIMIT and OFFSET.

• Use ORDER BY salary DESC to sort salaries in descending order.

• Use LIMIT 1 OFFSET n-1 to get the nth highest salary.

• For example, SELECT salary FROM employees ORDER BY salary DESC LIMIT 1 OFFSET 2 will give the 3rd highest salary.

LinkedHashSet is the data structure to use for storing data in order of insertion and uniqueness.

• LinkedHashSet maintains insertion order and ensures uniqueness of elements.

• It uses a combination of LinkedList and HashSet to achieve this.

• Example: LinkedHashSet set = new LinkedHashSet<>();

It depends on the specific use case and requirements of the project.

• SQL is better for structured data and complex queries

• NoSQL is better for unstructured data and scalability

• Consider the need for ACID compliance and data consistency

• Choose based on the project's requirements and scalability needs

It depends on the specific project requirements and team expertise.

• Consider the project requirements - Node.js is great for real-time applications, while Java is better for large-scale enterprise applications.

• Evaluate team expertise - If your team is more familiar with JavaScript, Node.js may be the better choice.

• Performance - Java is generally faster and more efficient than Node.js.

• Scalability - Java is known for its scalability, making it a good choice for growing applicati...read more

Using RestControllerAdvice to handle exceptions at controller level in Java

• Create a class annotated with @RestControllerAdvice to handle exceptions globally

• Use @ExceptionHandler annotation in the class to define methods to handle specific exceptions

• Return ResponseEntity with appropriate status code and error message in the exception handling methods

Closures in JavaScript are functions that have access to variables from their outer scope even after the outer function has finished executing.

• Closures allow functions to access variables from their parent function's scope

• They are created whenever a function is defined within another function

• Closures can be used to create private variables and functions

Implement a small error handling thread executor service project in Spring Boot.

• Create a Spring Boot project

• Implement a custom thread executor service

• Handle errors and exceptions in the executor service

• Use Spring Boot's error handling mechanisms

• Test the error handling functionality

Prototypal Inheritance in JavaScript is a way of creating objects based on existing objects.

• In JavaScript, each object has a prototype property which allows one object to inherit properties and methods from another object.

• When a property or method is accessed on an object, JavaScript will first look for it on the object itself, then on its prototype, and so on up the prototype chain.

• Prototypal Inheritance allows for code reusability and helps in creating a hierarchy of object...read more

Angular lifecycle hooks are methods that allow you to tap into specific points in a component's lifecycle.

• ngOnChanges: Called when an input property changes

• ngOnInit: Called once the component is initialized

• ngDoCheck: Called during every change detection run

• ngAfterContentInit: Called after content (ng-content) has been projected into the component

• ngAfterContentChecked: Called after every check of the projected content

• ngAfterViewInit: Called after the component's view has been ...read more

OOPs is a programming paradigm based on the concept of objects. Abstraction is the process of hiding implementation details from the user.

• OOPs stands for Object-Oriented Programming.

• Abstraction is achieved through encapsulation and inheritance.

• IOC container is a framework for implementing Inversion of Control.

• Application context is a container for holding beans in Spring Framework.