Coforge Tableau Developer Interview Questions and Answers

Program to print unique elements in an array in Java

• Create a HashSet to store unique elements

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

• Print the HashSet to get the unique elements

Data structures are ways of organizing and storing data in a computer so that it can be accessed and used efficiently.

• Arrays - a collection of elements of the same type

• Linked Lists - a sequence of nodes where each node contains a reference to the next node

• Stacks - a collection of elements with two main operations: push (add) and pop (remove)

• Queues - a collection of elements with two main operations: enqueue (add) and d...read more

OOPs stands for Object-Oriented Programming. It is a programming paradigm based on the concept of objects.

• OOPs focuses on creating objects that contain both data and functions.

• It emphasizes on encapsulation, inheritance, and polymorphism.

• Examples of OOPs languages are Java, C++, Python, etc.

OOPs is used for creating modular, reusable and maintainable code.

• Encapsulation: Hiding implementation details and exposing only necessary information.

• Inheritance: Reusing code and creating a hierarchy of classes.

• Polymorphism: Using a single interface to represent multiple entities.

• Abstraction: Reducing complexity by hiding unnecessary details.

• Examples: Java, C++, Python, Ruby, etc.

Inheritance is a mechanism in object-oriented programming where a new class is created by inheriting properties of an existing class.

• Inheritance allows code reuse and promotes code organization.

• The existing class is called the parent or superclass, and the new class is called the child or subclass.

• The child class inherits all the properties and methods of the parent class and can also add its own unique properties and ...read more

Polymorphism is the ability of an object to take on many forms.

• It allows objects of different classes to be treated as if they were objects of the same class.

• It is achieved through method overriding and method overloading.

• Example: A parent class Animal can have child classes like Dog, Cat, and Bird, each with their own unique implementation of the method 'makeSound'.

• Polymorphism makes code more flexible and reusable.

Abstraction is the process of hiding complex implementation details and exposing only the necessary information.

• Abstraction helps in reducing complexity and increasing efficiency.

• It allows us to focus on the essential features of an object or system.

• For example, a car can be abstracted as a vehicle with certain properties like speed, fuel efficiency, and seating capacity.

• Abstraction can be achieved through interfaces,

Encapsulation is the process of hiding implementation details and providing a public interface for accessing the functionality.

• Encapsulation helps in achieving data abstraction and information hiding

• It prevents unauthorized access to the internal details of an object

• It allows for easy modification of implementation without affecting the external code

• Example: A class with private variables and public methods

• Example: A b...read more

Remove duplicate objects from an array of multiple objects.

• Create a new array to store unique objects

• Loop through the original array and check if the object already exists in the new array

• If not, add it to the new array

• Return the new array

Maintain state by using a global variable or a state management system.

• Use a global variable to store the state and access it whenever needed.

• Use a state management system like Redux or MobX to manage the state.

• Avoid using local variables or closures to store state as they will be lost when the code is repeated.

• Consider using object-oriented programming principles to encapsulate state within objects.

• Use functional prog...read more

Design patterns are reusable solutions to common software problems. Android system uses various design patterns.

• MVC (Model-View-Controller) pattern is used in Android to separate UI logic from business logic.

• Singleton pattern is used to ensure only one instance of a class is created.

• Observer pattern is used to notify changes in data to multiple components.

• Builder pattern is used to simplify complex object creation.

• Adap...read more

C# is a programming language, ASP.NET is a web framework, and MVC is a design pattern for building web applications.

• C# is used to write code for various applications, including web applications.

• ASP.NET is a web framework that provides tools and libraries for building web applications.

• MVC is a design pattern that separates an application into three components: Model, View, and Controller.

• ASP.NET MVC is a web framework t...read more