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Vaadin interview questions and Answers

What Is Vaadin?
The Vaadin is a web application framework, open source platform and built on Google Web Toolkit (GWT) written in Java.

The Vaadin Framework is created and supported by Vaadin Ltd, a Finnish company founded 11 years ago and Vaadin licensed under the Apache 2.0 license.
The Vaadin platform includes a big set of web components, application starters, performance, accessibility and tools for building great looking apps faster in Java.

The Vaadin allows the implementation of HTML5 web user interfaces using the Java.

The components are built as standard HTML elements that can be used in any framework.

The Vaadin is 100% Java. No JavaScript or any other languages required. You don't need to know any languages other than Java to build great web applications.

What are the Vaadin goals?
The main goal of Vaadin is creating user interfaces for business applications.

We have followed the following rules i.e.
1.      Right tool for the right purpose
2.      Choice between declarative and dynamic UIs
3.      Simplicity and maintainability
4.      Tools should not limit your work
5.      And so on

How to install the Vaadin components?
The Vaadin components are typically installed with npm or Bower.

Prerequisites -
1.      JDK installed
2.      Eclipse Mars installed and working
3.      Vaadin plug-in installed
4.      Tomcat 8 installed and running
Steps in Vaadin Installation -
1.      Java installation
2.      IDE installation
3.      Application Server Requirements

How to use Vaadin?
I believe Vaadin is super easy to use. You just need Maven and a Java compiler. Make it easy on yourself though, and bring an IDE to the party.

Though you don’t really need an IDE, it does make your life easier, since there is a probably a Vaadin plugin for your IDE.

IDE plugin - The easiest way to get started is by using an IDE like Eclipse or NetBeans, and there are free plugins for both. If you have IntelliJ Ultimate, then Vaadin has a plugin for that too.

What are the features of Vaadin?
The following features of the Vaadin -
1.      You don't need to know any languages other than Java to build great web applications.
2.      You'll get your first Vaadin app running in minutes and you can continue until you have a simple UI built for a customer database.
3.      Vaadin Flow allows defining the HTML templates with automated client-server communication and data binding in case of using Polymer-based templates.
4.      Vaadin Flow includes Spring Frameworks.
5.      Router is an essential and core concept in Vaadin Flow and enables navigation via URLs
6.      Data binding is done via the Binder class and it allows synchronizing the values in input fields with server-side data models.

What Is Architecture Diagram of Vaadin?

What are the add-ons?
The Add-ons are the ways to share your own components between projects. Some add-ons are free and some are commercial or dual licensed.

The Vaadin web components, themes, layouts, and data sources inbuilt into the core library, many others are available as add-ons.

The add-ons are divided to the following categories -
1.      Themes
2.      UI components
3.      Data components
4.      Miscellaneous

What are Vaadin components?
The components are building blocks for modern web applications.

The Vaadin components is an evolving set of high quality user interface web components commonly needed in modern mobile and desktop business web applications.

The Vaadin has a comprehensive set of beautifully crafted, performing, and adaptable UI components for modern mobile first Web applications.

The Web Components looks like -
1.      vaadin-grid
2.      vaadin-board
3.      vaadin-list-box
4.      vaadin-button
5.      vaadin-dialog
6.      vaadin-charts
7.      vaadin-checkbox
8.      vaadin-combo-box
9.      vaadin-confirm-dialog
10. vaadin-tabs
11. and so on
By Anil Singh | Rating of this article (*****)

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