Modernize your legacy Java apps to modern web

Migrate your Swing, SWT, or JavaFX app to the modern web — with code you still recognize. Automate up to 85% of the modernization while keeping your logic, structure, and comments intact.

Start with the free Analyzer to analyze your code and get detailed estimates.
swing-to-vaadin
85%
or more of the code can be
automatically converted
60%
lower cost of modernizing
a legacy Java app
80%
lower effort of developers
and testers over rewrite
Modernization with Vaadin

Clean, familiar, and maintainable code after migration

The Modernization Toolkit generates readable, production-ready Vaadin code that mirrors your original project structure. Naming conventions, comments, and formatting are preserved, so your team stays productive with code they instantly recognize.

The transpiler transforms UI components line-by-line whenever possible,keeping the migration
transparent and easy to review.

See the Swing-to-Vaadin migration code example below.

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Swing

Vaadin Modernization Toolkit Swing Code Example

Vaadin

Vaadin Modernization toolkit code example
Migration analysis in minutes, not months

Find out exactly what can be automated before you migrate

The free Analyzer scans your legacy Java app to detect legacy dependencies and shows how much of your UI can be automatically migrated. Get a shareable report with automation percentage, effort estimate, and flagged manual tasks.

Run the free Analyzer and get a migration roadmap for your stakeholders.

Analyzer for Eclipse Analyzer for Maven

Ready to kill the tail on legacy dependencies and bring your Java Swing application to the future?

Download our white paper, ‘Modernizing Java Swing Applications: A Five-Step Blueprint for Decision-Makers,’ to learn how to automate your Swing-to-Web migration with the Vaadin Modernization Toolkit.
Vaadin Framework - Built on modern web standards

Give your application’s features
a new life on the latest
web standards

By migrating with the Vaadin Modernization Toolkit, your applications instantly benefit from modern Java features, W3C standards, and enterprise-ready UI components. Vaadin ensures your apps are not only modern, but also compliant out of the box with WCAG 2.1, EAA (European Accessibility Act) and have responsive layouts for desktop, tablet, and mobile.

This means your modernized app will meet compliance requirements, improve usability for all users, and stay aligned with evolving regulations - without extra work.
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Get the job done with automation

Many conventional Java modernization projects adopting a phased approach can take years to complete, and developers often lack the motivation to finish. The automation provided by the Vaadin Modernization Toolkit can refactor the bulk of your Java code so you can quickly kill the tail of legacy dependencies and move forward with an architecturally coherent new application.
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Fully customizable transformations

The Vaadin Modernization Toolkit includes a default set of transformation capabilities, enabling the most common features found in legacy frameworks. These can be extended with the APIs used in your application or customized if your application has tailored the legacy technology with non-standard behavior.
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Trusted by award-winning companies to create award-winning software

From the list of the most influential FinTechs to the Best SaaS from the Cloud Awards, companies rely on Vaadin to create cutting-edge applications that make a big impact. The Vaadin Modernization Toolkit gives you a boost to accelerate your Java migration to modern web apps.
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Java migration, not emulation

The Vaadin Modernization Toolkit helps migrate Java applications to Vaadin Flow, Vaadin’s open-source framework for building web applications with Java. After the migration, there will be no remaining dependencies on old frameworks such as Swing, SWT, or JavaFX. The Toolkit supplies useful features familiar to developers from old frameworks in a Feature Pack, but it does not emulate technologies like Swing.

Code readability built-in

We built the Modernization Toolkit to produce code that humans can read and maintain. Your transformed application sources retain the original structure, naming conventions, comments, and whitespace. Changes made by the transpiler are almost always applied within the same line of code, meaning your developers can confidently take ownership.

Fine-tuning: Reach your target automation with a fixed-price guarantee

The engineers at Vaadin offer a fixed-price Fine-tuning service to improve the Standard Rules, Custom Rules, and Feature Pack to reach a higher degree of automation for your application. The transpiler can also be iteratively improved to automate a higher percentage of the work.
Customer case

Procountor made a UX-first accounting software with Vaadin

When Apple dropped support for their own JVM, we had to start supporting a Swing version of our app as well. The abstraction layer made it a natural choice for us to do the same with Vaadin, knowing that the API was so similar to both Swing and AWT. And that's what we did. Quite successfully I might add.

Lauri Lehtonen
CTO, procountor
lufthansa
rockwell
primerica
hsbc
tsystems
jnj
Talk to our Team

Modernization, not just migration

Book a free consultation with our expert to learn more how the Modernization Toolkit turns your old apps into modern web apps.

Make the app usable with modern
devices on web browser
A cost-effective transition
Improved look and feel
Faster performance
Moving the app to run in the cloud