10+ Amazon Interview Questions and Answers

Redux is a predictable state container for JavaScript apps. It helps manage application state in a single immutable store.

• Redux is a state management library for JavaScript applications.

• It follows a unidirectional data flow architecture.

• Redux architecture consists of actions, reducers, store, and middleware.

• Actions are payloads of information that send data from the application to the store.

• Reducers specify how the application's state changes in response to actions.

• Store hold...read more

Callback functions are functions passed as arguments to other functions to be executed later.

• Used in event handling, asynchronous operations, and to achieve higher order functions

• Disadvantages include callback hell, difficult to read and maintain code, and potential for memory leaks

• Example: setTimeout function in JavaScript takes a callback function as an argument

Improving website performance involves optimizing code, reducing server requests, and utilizing caching techniques.

• Optimize code by removing unnecessary code, minifying and compressing files, and using efficient algorithms.

• Reduce server requests by combining files, using asynchronous loading, and implementing lazy loading for images and videos.

• Utilize caching techniques such as browser caching, server-side caching, and content delivery networks (CDNs) to store and deliver con...read more

An Android app is a software application designed to run on Android devices. Android versions are named after desserts, with the latest being Android 12.

• Android apps are developed using Java or Kotlin programming languages.

• Android versions are named after desserts, such as KitKat, Oreo, and Pie.

• SDK (Software Development Kit) is a set of tools used to develop apps for Android.

• ADK (Accessory Development Kit) is used to create hardware accessories that work with Android devices.

Shadow DOM is a way to encapsulate the styling and structure of a web component, preventing styles from leaking out or clashing with the rest of the page.

• Shadow DOM allows for creating self-contained components with their own DOM tree and styling.

• It helps in preventing styles from the main document affecting the component and vice versa.

• Shadow DOM can be created using the 'attachShadow' method in JavaScript.

• Example:

  const shadowRoot = document.getElementById('myComponent').a...read more

CORS stands for Cross-Origin Resource Sharing, a security feature that allows servers to specify who can access their resources.

• CORS is a security feature implemented by browsers to prevent unauthorized access to resources on a different origin.

• It allows servers to specify which origins are allowed to access their resources using HTTP headers like Access-Control-Allow-Origin.

• CORS is important for protecting sensitive data and preventing cross-site request forgery (CSRF) attac...read more

There are various apps in Android to develop, such as Android Studio, IntelliJ IDEA, Eclipse, etc.

• Android Studio is the official IDE for Android app development

• IntelliJ IDEA is a popular IDE for Android development

• Eclipse with ADT plugin can also be used for Android development

Implementing data security in Apex to prevent unauthorized DML operations on fields and objects.

• Use field-level security to restrict access to sensitive fields

• Implement object-level security using profiles and permission sets

• Utilize Apex sharing rules to control record-level access

• Consider using custom validation rules to enforce data integrity

• Implement triggers to enforce additional business logic and security measures

A .dk file in Android is a Dex file, which is a compiled file format used by the Dalvik Virtual Machine.

• Dex files contain compiled code and resources for an Android application.

• They are generated by the Android build tools during the build process.

• Dex files are executed by the Dalvik Virtual Machine on Android devices.

Pillars of OOPs concepts are Abstraction, Encapsulation, Inheritance, and Polymorphism. Types of inheritance include Single, Multiple, Multilevel, and Hierarchical.

• Abstraction focuses on hiding the implementation details and showing only the necessary features.

• Encapsulation bundles the data and methods that operate on the data into a single unit.

• Inheritance allows a class to inherit properties and behavior from another class.

• Types of inheritance include Single (one class inhe...read more

Grunt in Android is a build automation tool that helps in automating repetitive tasks like compiling code, running tests, and deploying apps.

• Grunt is a JavaScript task runner that can be used to automate various tasks in Android development.

• It can be used to compile code, run tests, minify files, and deploy apps.

• Grunt uses a configuration file called 'Gruntfile.js' to define tasks and their configurations.

• Plugins can be added to Grunt to extend its functionality and perform s...read more

Python code to reverse a string using slicing

• Use string slicing with a step of -1 to reverse the string

• Example: 'hello'[::-1] will return 'olleh'

A jar file is a Java archive file that contains compiled Java classes and resources.

• A jar file is created using the jar command in Java.

• It is used for packaging Java classes and resources into a single file for distribution.

• Jar files can be executed using the Java Runtime Environment (JRE).

Integration practices involve connecting different systems to share data and functionality.

• Use APIs to connect systems and exchange data

• Implement middleware like MuleSoft or Dell Boomi for seamless integration

• Leverage Salesforce Connect to access external data sources within Salesforce

• Consider batch processing for large data transfers

• Implement error handling and monitoring for robust integrations

VMware is a virtualization software company that provides cloud computing and platform virtualization software and services.

• VMware is a company specializing in virtualization software.

• It allows multiple operating systems to run on a single physical machine.

• VMware products include VMware Workstation, VMware Fusion, and VMware vSphere.

• VMware helps in reducing hardware costs and increasing efficiency in IT environments.