AnnotatedMethodArgumentResolver class final

Resolves parameters of handler methods annotated with request parameter annotations in JetLeaf's web request handling system.

An AnnotatedMethodArgumentResolver is responsible for:

• Inspecting method parameters at runtime.
• Detecting annotations that are either RequestParameter or annotated with RequestParameter.
• Locating a corresponding Resolver (via ResolvedBy) to extract values from the ServerHttpRequest.

This resolver allows developers to define custom parameter resolution strategies using annotations on method parameters, enabling a clean separation between controller logic and request parsing.

Resolution Workflow

1. Annotation Discovery: Collects all direct annotations on a parameter.
2. Type Matching: Checks if an annotation is a RequestParameter or is meta-annotated with RequestParameter.
3. Resolver Extraction: Looks for a ResolvedBy annotation on the annotation class to retrieve the resolver instance.
4. Value Resolution: Uses the resolver to extract the argument value from the incoming request.
5. Returns null if no suitable resolver is found.

Example

class UserController {
  void getUser(
    @RequestParam('id') String id,
    @RequestParam('verbose') bool verbose
  ) {}
}

final resolver = AnnotatedMethodArgumentResolver();
final param = HandlerMethod(UserController.getUser).getParameter('id');
final value = await resolver.resolveArgument(param, request, response, handler);

Design Notes

• This class is stateless and can be reused across multiple requests.
• Supports annotation-driven parameter resolution via RequestParameter and ResolvedBy.
• Reflection failures while inspecting annotation metadata are silently ignored, ensuring robust request handling.
• Designed for internal use in the JetLeaf request dispatch pipeline.

Implemented types

• MethodArgumentResolver

Constructors

AnnotatedMethodArgumentResolver(ResolverContext _context)

Resolves parameters of handler methods annotated with request parameter annotations in JetLeaf's web request handling system.

const

Properties

hashCode → int

The hash code for this object.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

canResolve(Parameter param) → bool

Returns true if this resolver supports the given param.

override

getResolver(Source source) → Resolver?

Retrieves the Resolver associated with a given source (parameter).

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

resolveArgument(Parameter param, ServerHttpRequest req, ServerHttpResponse res, HandlerMethod handler, [Object? ex, StackTrace? st]) → Future<Object?>

Resolves the argument value for the given param.

override

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited