Amazon Transportation Services Software Developer Interview Questions and Answers

A closure is a function that has access to its own scope, the scope in which it was defined, and the global scope.

• A closure is created when a function is defined inside another function.

• The inner function has access to the variables and parameters of the outer function, even after the outer function has finished executing.

• Closures are useful for creating private variables and functions in JavaScript.

• They can also be us...read more

Encapsulation is the process of hiding internal details and providing a public interface for accessing and manipulating data.

• Encapsulation bundles data and methods together into a single unit.

• It helps in achieving data abstraction and data hiding.

• By encapsulating data, we can control access to it and prevent unauthorized modifications.

• Encapsulation promotes code reusability and maintainability.

• Example: A class in objec...read more

Inheritance is a concept in object-oriented programming where a class inherits properties and behaviors from another class.

• Inheritance allows for code reuse and promotes the concept of hierarchy.

• The class that is being inherited from is called the superclass or base class.

• The class that inherits from the superclass is called the subclass or derived class.

• The subclass can access the public and protected members of the s...read more

Abstraction is the process of simplifying complex systems by focusing on essential details.

• Abstraction involves hiding unnecessary details and exposing only relevant information.

• It allows developers to create models or representations that capture the essential aspects of a system.

• Abstraction helps in managing complexity, improving code reusability, and enhancing maintainability.

• For example, in object-oriented programm...read more

Polymorphism is the ability of an object to take on many forms. It allows objects of different classes to be treated as the same type.

• Polymorphism is a fundamental concept in object-oriented programming.

• It enables code reusability and flexibility.

• Polymorphism can be achieved through method overriding and method overloading.

• Example: A parent class Animal can have multiple child classes like Dog, Cat, and Bird. They can ...read more