Key interfaces

These interfaces define the most important extension points in Mateu’s public DSL.

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Component

The base interface for fluent UI components.

public interface Component {

  default Map<String, String> attributes() { ... }

  default Map<String, Object> properties() { ... }

  default String style() { ... }

  default String cssClasses() { ... }
}

Any type implementing io.mateu.uidl.fluent.Component can be embedded in fluent UIs and also inside declarative pages.

This is one of the key bridges between declarative and fluent Mateu.

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ComponentTreeSupplier

Use this when a class should return its UI explicitly instead of being inferred declaratively.

Use it for:

• custom pages
• advanced composition
• full fluent UIs

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ContentSupplier

Marks a type that exposes child components through content().

Used in layout-like and container-like components.

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ActionSupplier

Marks a type that exposes executable actions through actions().

Useful in page-like components such as the fluent Page.

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TriggersSupplier

Marks a type that provides a list of triggers dynamically from the request context.

Use it when triggers should not be static.

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AppSupplier

Specialized extension point for classes that return a fluent App.

App getApp(HttpRequest httpRequest);

Use it when the whole application shell is produced fluently.

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UISupplier

Provides fluent UI metadata.

UI getUI(HttpRequest httpRequest);

Useful when page metadata should be generated programmatically.

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CrudRepository

This is one of the central interfaces for CRUD-oriented Mateu applications.

Use it when Mateu should read, save, list, and delete entities through a repository abstraction.

Typical responsibilities:

• findById
• save
• findAll
• deleteAllById

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LookupOptionsSupplier

Defines how a lookup field searches available options.

Use it with @Lookup.

In real applications, this is usually a Spring bean so it can inject repositories, services, or API clients.

Typical use cases:

• remote relationships
• searchable dropdowns
• large datasets
• pageable option lists

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LabelSupplier

Defines how Mateu resolves the display label for a selected id/value.

Use it with @Lookup when the raw value is not enough for UI rendering.

In real applications, this is usually a Spring bean.

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BeanProvider

Abstraction for dependency lookup.

public interface BeanProvider {
  <T> T getBean(Class<T> clazz);
  <T> Collection<T> getBeans(Class<T> clazz);
}

This is more infrastructure-oriented, but still part of the public surface of the DSL.

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Mental model

Mateu interfaces mostly define extension points in four categories:

• fluent UI composition
• CRUD integration
• dynamic option/label resolution
• dependency and runtime integration