Vaadin Blog
Java Bean Validation: A Comprehensive Introduction and Best Practices
Jakarta Bean Validation (previously known as Java Bean Validation) allows you to define data validations using annotations in your Java Beans. Its motto is "constrain once, validate everywhere". Available implementations Jakarta Bean Validation is an API defined by the JSR 380. Currently, there are ...
Become a web app development expert with free training videos
To help developers accelerate their adoption of the latest Vaadin technology, we have decided to make a part of our training videos available to all community members for free. The free offering contains all beginner level courses for both Vaadin 8 and 10+ and is available in training videos. After ...
Building a dynamic web form with validation
When building business web apps, one of the most common tasks is data entry, that is, lots of webforms bound to domain objects or POJOs, validated against sometimes complex logic and finally persisted in a database or perhaps over REST to a remote server. In this tutorial, we walk through the ...
5 tips to get your issue solved quicker in open source projects
Asking for help is one of the easiest and most efficient ways to contribute to OSS projects - if you do it right. Last week I discussed code contributions, which is not easy and often takes a lot of time for beginners. With these tips, you can get your own problem solved and also help the project, ...
How to Measure Migration Effort with Migration Assessment
Desktop or Web applications based on deprecated technologies tend to become more expensive to maintain, are no longer supported, or simply have a drop in performance that pushes users away. Most often, the solution is to migrate to a modern platform that can ensure that your business Web ...
How to become an open source contributor?
We are utilizing a lot of Open Source products in our life daily. Sometimes we pay some money for them, in one way or another, but quite often we are just their users. To keep these awesome projects alive, we should at least sometimes try to contribute, give something back to the project. There are ...
Uploads and downloads, inputs and outputs
Vaadin Upload asks the developer to provide an OutputStream where the framework can stream the file content. Vaadin StreamResource (~ download) asks the developer to provide an InputStream the framework can read and stream to a user. Intuitive? Not really, unless you have accustomed to this ...
Integrate JQuery into Vaadin Flow
JQuery used to be one of the top JavaScript libraries and it is still really popular today. This tutorial demonstrates three alternative ways to integrate jQuery in your Vaadin project and check that it’s loaded. Note This tutorial requires Vaadin 14 in npm mode (this is the default mode). Option ...
Year in Review from a Fresh Vaadiner’s Perspective
As another year of fighting for simplicity nears its end, we’re taking a look back at what we have done in 2018 and what the future holds in store for us. Even though I’ve joined the Vaadin team quite recently, I had the chance to witness some of the following developments first-hand. Read on to ...