Unify Technologies Interview Questions and Answers

To reverse a string and find the occurrence of a character in Java.

• Use StringBuilder to reverse the string.

• Use a loop to iterate through the string and count the occurrences of the character.

• Use the charAt() method to access individual characters in the string.

To take a screenshot in Selenium, use the getScreenshotAs method

• Create a WebDriver instance

• Use the getScreenshotAs method to capture the screenshot

• Save the screenshot to a file using File class

Getter and setter methods are used to access and modify the values of private variables in a class.

• Create a method with the prefix 'get' followed by the variable name to retrieve its value.

• Create a method with the prefix 'set' followed by the variable name to set its value.

• Ensure the getter method returns the value of the variable and the setter method updates the variable with the passed value.

Object-oriented programming paradigm and its four pillars: Inheritance, Encapsulation, Abstraction, Polymorphism

• Inheritance: Allows a class to inherit properties and behavior from another class

• Encapsulation: Bundling data and methods that operate on the data into a single unit

• Abstraction: Hiding the complex implementation details and showing only the necessary features

• Polymorphism: Ability to present the same interface...read more

A simple Todo list application using Reactjs

• Create a new React project using create-react-app

• Implement a component for adding new tasks

• Implement a component for displaying the list of tasks

• Add functionality to mark tasks as completed

• Style the Todo list using CSS or a UI library like Material-UI

To add buttons for delete, create a button component with a delete function.

• Create a Button component with a delete function

• Pass a unique identifier for each item to be deleted

• Use onClick event to trigger the delete function

Frontend refers to the client-side part of a web application, focusing on user interface and user experience.

• Includes technologies like HTML, CSS, and JavaScript.

• Frameworks such as React, Angular, and Vue.js are commonly used.

• Responsible for layout, design, and interactivity of web pages.

• Ensures responsiveness and accessibility across devices.

• Communicates with backend services via APIs to fetch and display data.

The backend is the server-side part of a web application, handling data processing, storage, and business logic.

• Handles server-side logic and database interactions.

• Examples include Node.js, Java, Python, and Ruby on Rails.

• Communicates with the frontend via APIs (e.g., RESTful services).

• Manages user authentication and authorization.

• Processes data and performs calculations before sending results to the frontend.

Converting a JavaScript object to an array of objects allows for easier manipulation and iteration over the data structure.

• Use Object.entries(): This method returns an array of a given object's own enumerable string-keyed property [key, value] pairs.

• Example: const obj = { a: 1, b: 2 }; const arr = Object.entries(obj).map(([key, value]) => ({ key, value })); // [{ key: 'a', value: 1 }, { key: 'b', value: 2 }]

• Use Obje...read more

Redux is a predictable state container for JavaScript apps, often used with React for managing application state.

• Centralized State Management: Redux maintains the application state in a single store, making it easier to manage and debug.

• Actions and Reducers: State changes are made through actions (plain objects) and reducers (functions that specify how the state changes).

• Middleware Support: Redux allows middleware like...read more