DependencyKind enum

The form of an injection point that a Dependency describes: one bean, all beans of a type, a provider, a @Value, and so on.

The generator picks the kind from the parameter or field it reads, and validateBeanGraph checks each kind in its own way (a provider is never required, a @Lazy point never closes a cycle). You choose one yourself only through the Dependency constructors of a hand-written definition. The forms, as the generator sees them:

@Service()
class Checkout {
  Checkout(
    this.payments,          // single
    this.validators,        // collection (List<Validator>)
    this.byName,            // map (Map<String, Exporter>)
    this.audit,             // provider (ObjectProvider<Audit>)
    @Value(r'${shop.currency:EUR}') this.currency, // value
  );
  final Payments payments;
  final List<Validator> validators;
  final Map<String, Exporter> byName;
  final ObjectProvider<Audit> audit;
  final String currency;
}

Spring (Java): no public equivalent; Spring discovers the same kinds of injection points by reflection (DependencyDescriptor):

Checkout(Payments payments, List<Validator> validators,
    Map<String, Exporter> byName, ObjectProvider<Audit> audit,
    @Value("${shop.currency:EUR}") String currency) { ... }

Inheritance

Object
Enum
DependencyKind

Available extensions

EnumName

Values

single → const DependencyKind: One bean (T, or T? when it may be missing).
collection → const DependencyKind: All beans of a type (List<T> or Set<T>).
map → const DependencyKind: All beans of a type by bean name (Map<String, T>).
provider → const DependencyKind: A lazy ObjectProvider<T> (or ObjectFactory<T>, jakarta Provider<T>): nothing is resolved before it is used, so it is never required and never part of a cycle.
lazy → const DependencyKind: A @Lazy single bean: checked like single (present, unambiguous) but resolved on first use, so never part of a cycle.
value → const DependencyKind: A @Value expression; a required one must have a value at startup.
resource → const DependencyKind: A @Resource field or setter: the bean named Dependency.name, or with Dependency.fallbackToType a bean of the type when no bean has that name.

Properties

hashCode → int: The hash code for this object.
no setterinherited
index → int: A numeric identifier for the enumerated value.
no setterinherited
name → String: Available on Enum, provided by the EnumName extension
The name of the enum value.
no setter
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited

Methods

noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
toString() → String: A string representation of this object.
inherited

Operators

operator ==(Object other) → bool: The equality operator.
inherited

Constants

values → const List<DependencyKind>: A constant List of the values in this enum, in order of their declaration.