Scala Reflection Library2.13.7 < Back
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# 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 `Annotation`s, see the Reflection Guide: Annotations, Names, Scopes, and More

  Definition Classes
    api
- Annotation
- AnnotationApi
- AnnotationExtractor
- JavaArgument
- JavaArgumentApi

c

scala.reflect.api.Annotations

# AnnotationExtractor

###

#### abstract class AnnotationExtractor extends AnyRef

An extractor class to create and pattern match with syntax `Annotation(tpe, scalaArgs, javaArgs)`. Here, `tpe` is the annotation type, `scalaArgs` the payload of Scala annotations, and `javaArgs` the payload of Java annotations.

Source
  Annotations.scala

Linear Supertypes
AnyRef, Any
Type Hierarchy
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Ordering

1. Alphabetic
2. By Inheritance

Inherited

1. AnnotationExtractor
2. AnyRef
3. Any

Implicitly

1. by any2stringadd
2. by StringFormat
3. by Ensuring
4. by ArrowAssoc

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Visibility

1. Public
2. Protected

### Instance Constructors

1.  new AnnotationExtractor()

### Abstract Value Members

1.  abstract def apply(tpe: Universe.Type, scalaArgs: List[Universe.Tree], javaArgs: ListMap[Universe.Name, Universe.JavaArgument]): Universe.Annotation
   Annotations
     @deprecated
   Deprecated

     (Since version 2.11.0) use `apply(tree: Tree): Annotation` instead

2.  abstract def unapply(ann: Universe.Annotation): Option[(Universe.Type, List[Universe.Tree], ListMap[Universe.Name, Universe.JavaArgument])]
   Annotations
     @deprecated
   Deprecated

     (Since version 2.11.0) use `Annotation.tree` to inspect annotation arguments

### Concrete Value Members

1.  final def !=(arg0: Any): Boolean
   Definition Classes
     AnyRef → Any
2.  final def ##: Int
   Definition Classes
     AnyRef → Any
3.  def +(other: String): String
   Implicit
     This member is added by an implicit conversion from Universe.AnnotationExtractor toany2stringadd[Universe.AnnotationExtractor] performed by method any2stringadd in scala.Predef.
   Definition Classes
     any2stringadd
4.  def ->[B](y: B): (Universe.AnnotationExtractor, B)
   Implicit
     This member is added by an implicit conversion from Universe.AnnotationExtractor toArrowAssoc[Universe.AnnotationExtractor] performed by method ArrowAssoc in scala.Predef.
   Definition Classes
     ArrowAssoc
   Annotations
     @inline()
5.  final def ==(arg0: Any): Boolean
   Definition Classes
     AnyRef → Any
6.  def apply(tree: Universe.Tree): Universe.Annotation
7.  final def asInstanceOf[T0]: T0
   Definition Classes
     Any
8.  def clone(): AnyRef
   Attributes
     protected[lang]
   Definition Classes
     AnyRef
   Annotations
     @throws(classOf[java.lang.CloneNotSupportedException]) @native()
9.  def ensuring(cond: (Universe.AnnotationExtractor) => Boolean, msg: => Any): Universe.AnnotationExtractor
   Implicit
     This member is added by an implicit conversion from Universe.AnnotationExtractor toEnsuring[Universe.AnnotationExtractor] performed by method Ensuring in scala.Predef.
   Definition Classes
     Ensuring
10.  def ensuring(cond: (Universe.AnnotationExtractor) => Boolean): Universe.AnnotationExtractor
    Implicit
      This member is added by an implicit conversion from Universe.AnnotationExtractor toEnsuring[Universe.AnnotationExtractor] performed by method Ensuring in scala.Predef.
    Definition Classes
      Ensuring
11.  def ensuring(cond: Boolean, msg: => Any): Universe.AnnotationExtractor
    Implicit
      This member is added by an implicit conversion from Universe.AnnotationExtractor toEnsuring[Universe.AnnotationExtractor] performed by method Ensuring in scala.Predef.
    Definition Classes
      Ensuring
12.  def ensuring(cond: Boolean): Universe.AnnotationExtractor
    Implicit
      This member is added by an implicit conversion from Universe.AnnotationExtractor toEnsuring[Universe.AnnotationExtractor] performed by method Ensuring in scala.Predef.
    Definition Classes
      Ensuring
13.  final def eq(arg0: AnyRef): Boolean
    Definition Classes
      AnyRef
14.  def equals(arg0: AnyRef): Boolean
    Definition Classes
      AnyRef → Any
15.  def finalize(): Unit
    Attributes
      protected[lang]
    Definition Classes
      AnyRef
    Annotations
      @throws(classOf[java.lang.Throwable])
16.  final def getClass(): Class[_ <: AnyRef]
    Definition Classes
      AnyRef → Any
    Annotations
      @native()
17.  def hashCode(): Int
    Definition Classes
      AnyRef → Any
    Annotations
      @native()
18.  final def isInstanceOf[T0]: Boolean
    Definition Classes
      Any
19.  final def ne(arg0: AnyRef): Boolean
    Definition Classes
      AnyRef
20.  final def notify(): Unit
    Definition Classes
      AnyRef
    Annotations
      @native()
21.  final def notifyAll(): Unit
    Definition Classes
      AnyRef
    Annotations
      @native()
22.  final def synchronized[T0](arg0: => T0): T0
    Definition Classes
      AnyRef
23.  def toString(): String
    Definition Classes
      AnyRef → Any
24.  final def wait(): Unit
    Definition Classes
      AnyRef
    Annotations
      @throws(classOf[java.lang.InterruptedException])
25.  final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
      AnyRef
    Annotations
      @throws(classOf[java.lang.InterruptedException])
26.  final def wait(arg0: Long): Unit
    Definition Classes
      AnyRef
    Annotations
      @throws(classOf[java.lang.InterruptedException]) @native()

### Deprecated Value Members

1.  def formatted(fmtstr: String): String
   Implicit
     This member is added by an implicit conversion from Universe.AnnotationExtractor toStringFormat[Universe.AnnotationExtractor] performed by method StringFormat in scala.Predef.
   Definition Classes
     StringFormat
   Annotations
     @deprecated @inline()
   Deprecated

     (Since version 2.12.16) Use `formatString.format(value)` instead of `value.formatted(formatString)`, or use the `f""` string interpolator. In Java 15 and later, `formatted` resolves to the new method in String which has reversed parameters.

2.  def →[B](y: B): (Universe.AnnotationExtractor, B)
   Implicit
     This member is added by an implicit conversion from Universe.AnnotationExtractor toArrowAssoc[Universe.AnnotationExtractor] performed by method ArrowAssoc in scala.Predef.
   Definition Classes
     ArrowAssoc
   Annotations
     @deprecated
   Deprecated

     (Since version 2.13.0) Use `->` instead. If you still wish to display it as one character, consider using a font with programming ligatures such as Fira Code.

### Inherited from AnyRef

### Inherited from Any

### Inherited by implicit conversion any2stringadd fromUniverse.AnnotationExtractor to any2stringadd[Universe.AnnotationExtractor]

### Inherited by implicit conversion StringFormat fromUniverse.AnnotationExtractor to StringFormat[Universe.AnnotationExtractor]

### Inherited by implicit conversion Ensuring fromUniverse.AnnotationExtractor to Ensuring[Universe.AnnotationExtractor]

### Inherited by implicit conversion ArrowAssoc fromUniverse.AnnotationExtractor to ArrowAssoc[Universe.AnnotationExtractor]

### Ungrouped