Conditional class final

An annotation that conditionally enables or disables JetLeaf-managed constructs such as Component, Pod, or configuration classes based on one or more declarative Condition evaluators.

The Conditional annotation is a reflective directive that instructs the JetLeaf framework to include the annotated type or method only if all specified conditions evaluate to true during pod resolution.

Purpose

In a modular JetLeaf application, certain Components or configuration classes may only be applicable under specific runtime contexts, such as environment, platform, or other application state. Conditional provides a declarative and compile-time safe mechanism to express these contextual dependencies.

Behavior

  • Each class in conditions must implement Condition.
  • Each condition class must have a const constructor so that Conditional can be used as a compile-time constant.
  • JetLeaf evaluates all conditions in the order they are declared. The annotated construct is processed only if every condition returns true via Condition.matches.

Example

class OnProductionEnvironmentCondition implements Condition {
  const OnProductionEnvironmentCondition();

  @override
  bool matches(Environment env) => env.isProduction();
}

@Conditional([OnProductionEnvironmentCondition()])
class ProductionDataSourceConfig {}

Declaring conditions as const ensures deterministic evaluation and eliminates runtime instantiation overhead.

  • Condition: Interface that defines the logical predicate for conditional activation.
  • ConditionalContext: JetLeaf context responsible for evaluating conditions and initializing pods.
Annotations
  • @Target.new({TargetKind.classType, TargetKind.method})

Constructors

Conditional(List<Condition> conditions)
An annotation that conditionally enables or disables JetLeaf-managed constructs such as Component, Pod, or configuration classes based on one or more declarative Condition evaluators.
const

Properties

annotationType → Type
Returns the annotation _type of this annotation.
no setter
conditions → List<Condition>
Condition classes that must match for the annotated type or method to be processed.
final
hashCode → int
The hash code for this object.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

equalizedProperties() → List<Object?>
Mixin-style contract for value-based equality, hashCode, and toString.
equals(Object other) → bool
Checks whether the given object is logically equivalent to this annotation.
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
Returns a string representation of this annotation.

Operators

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

Constants

FIELD_KEY → const String
The key used to store or reference condition information for a Conditional annotation. It matches conditions in Conditional