Introspected class

Marks a class whose properties, constructor and methods the generator describes, so the framework can read and fill its objects without reflection.

Dart has no runtime reflection in Flutter or compiled programs, so anything that must list or set the fields of an object it did not write needs a description generated at build time. Put @Introspected() on the classes that are bound from requests or configuration, validated, turned into JSON or used in SpEL expressions. Micronaut's @Introspected works the same way.

// A form that is validated and bound from request data.
@Introspected()
class Address {
  @NotBlank()
  String city = '';
  String? zip;
}

// The generated BeanIntrospection is registered by the module, so:
BeanWrapper(Address()).setPropertyValue('city', 'Lyon');

Spring (Java): no annotation is needed; Spring discovers properties at runtime with java.beans.Introspector (getters and setters) and reflection. Micronaut's @Introspected is the closest match.

class Address {
  private String city;
  public String getCity() { return city; }
  public void setCity(String city) { this.city = city; }
}

Classes of other packages (a shared DTO package, ...) are introspected by listing them: @Introspected(classes: [ExternalDto]) on any class of the scanned package. Classes of the same package used by an introspected class (property and constructor types) are introspected automatically.

@Introspected() describes everything about a class. A class the build finds in use without it (a controller's return type, a request body, a client's answer) is described only for that use, see IntrospectionPart; the annotation is the way to ask for all of it.

Constructors

Properties

Methods

Operators

spring_core_dart library