Mateu lets you define your UI in plain Java.

Instead of building and maintaining a separate frontend, you describe the UI using backend code and Mateu renders it automatically.

The core idea

A Mateu UI is usually expressed with:

• Java classes
• fields for state
• methods or callables for actions
• annotations for UI behavior

For example:

@UI("")
public class Counter {

  @ReadOnly
  int count = 0;

  @Button
  Runnable increment = () -> count++;

}

Mateu turns that definition into a working UI.

What Mateu generates

From your Java definition, Mateu can render things like:

• forms
• tables
• layouts
• buttons and actions
• navigation structures

Two ways to define UIs

Mateu supports two main styles:

Declarative

You describe the UI directly with classes, fields, methods, and annotations.

This is the simplest and most direct approach.

Imperative / fluent

You build the UI using fluent Java APIs and component records when you want more control.

Why this matters

This approach reduces:

• duplicated models
• frontend/backend synchronization
• manual API glue
• accidental complexity

The result is a simpler way to build business applications.