Packages

•  package root

  Definition Classes

  root

•  package scala

  Definition Classes

  root

•  package reflect

  Definition Classes

  scala

•  package api

  EXPERIMENTAL

  EXPERIMENTAL

  The Scala Reflection API (located in scala-reflect.jar).

  In Scala 2.10.0, the Scala Reflection API and its implementation have an "experimental" status. This means that the API and the docs are not complete and can be changed in binary- and source-incompatible manner in 2.10.1. This also means that the implementation has some known issues.

  The following types are the backbone of the Scala Reflection API, and serve as a good starting point for information about Scala Reflection:

  • scala.reflect.api.Symbols
  • scala.reflect.api.Types
  • scala.reflect.api.Mirrors
  • scala.reflect.api.Universe

  For more information about Scala Reflection, see the Reflection Guide

  Definition Classes

  reflect

•  trait Annotations extends AnyRef

  EXPERIMENTAL

  EXPERIMENTAL

  This trait provides annotation support for the reflection API.

  In Scala, annotations belong to one of the two categories:

  • Java annotations: annotations on definitions produced by the Java compiler, i.e., subtypes of java.lang.annotation.Annotation attached to program definitions.
  • Scala annotations: annotations on definitions or types produced by the Scala compiler.

  When a Scala annotation that inherits from scala.annotation.StaticAnnotation is compiled, it is stored as special attributes in the corresponding classfile, and not as a Java annotation. Note that subclassing just scala.annotation.Annotation is not enough to have the corresponding metadata persisted for runtime reflection.

  Both Java and Scala annotations are represented as typed trees carrying constructor invocations corresponding to the annotation. For instance, the annotation in @ann(1, 2) class C is represented as q"@new ann(1, 2)".

  Unlike Java reflection, Scala reflection does not support evaluation of constructor invocations stored in annotations into underlying objects. For instance it's impossible to go from @ann(1, 2) class C to ann(1, 2), so one has to analyze trees representing annotation arguments to manually extract corresponding values. Towards that end, arguments of an annotation can be obtained via annotation.tree.children.tail.

  For more information about Annotations, see the Reflection Guide: Annotations, Names, Scopes, and More

  Definition Classes

  api

• Annotation
• AnnotationApi
• AnnotationExtractor
• JavaArgument
• JavaArgumentApi

scala.reflect.api.Annotations

Annotation

Companion class AnnotationExtractor