Annotation
Base interface implicitly implemented by all annotation interfaces. See Kotlin language documentation for more information on annotations.
Extension Properties
annotationClass
Returns a KClass instance corresponding to the annotation type of this annotation.
val <T : Annotation> T.annotationClass: KClass<out T>
Inheritors
AssociatedObjectKey
Makes the annotated annotation class an associated object key.
annotation class AssociatedObjectKey
BetaInteropApi
Marks Objective-C and Swift interoperability API as Beta.
annotation class BetaInteropApi
BuilderInference
Allows to infer generic type arguments of a function from the calls in the annotated function parameter of that function.
annotation class BuilderInference
CCall
annotation class CCall
CEnumEntryAlias
Denotes property that is an alias to some enum entry.
annotation class CEnumEntryAlias
CEnumVarTypeSize
Stores instance size of the type T: CEnumVar.
annotation class CEnumVarTypeSize
CName
Makes top level function available from C/C++ code with the given name.
annotation class CName
ConsistentCopyVisibility
In previous versions of Kotlin, the generated 'copy' method of a data class always had public visibility, even if the primary constructor was non-public. That exposed the non-public constructor of the data class.
annotation class ConsistentCopyVisibility
ContextFunctionTypeParams
Signifies that the annotated functional type has the prefix of size count
for context receivers.
Thus, @ContextFunctionTypeParams(2) @ExtensionFunctionType Function4<String, Int, Double, Byte, Unit>
is a normalized representation of
context(String, Int) Double.(Byte) -> Unit
.
annotation class ContextFunctionTypeParams
CStruct
annotation class CStruct
Deprecated
Marks the annotated declaration as deprecated.
annotation class Deprecated
DeprecatedSinceKotlin
Marks the annotated declaration as deprecated. In contrast to Deprecated, severity of the reported diagnostic is not a constant value,
but differs depending on the API version of the usage (the value of the -api-version
argument when compiling the module where
the usage is located). If the API version is greater or equal than hiddenSince, the declaration will not be accessible from the code
(as if it was deprecated with level DeprecationLevel.HIDDEN), otherwise if the API version is greater or equal than errorSince,
the usage will be marked as an error (as with DeprecationLevel.ERROR), otherwise if the API version is greater or equal
than warningSince, the usage will be marked as a warning (as with DeprecationLevel.WARNING), otherwise the annotation is ignored.
annotation class DeprecatedSinceKotlin
DslMarker
When applied to annotation class X specifies that X defines a DSL language
annotation class DslMarker
EagerInitialization
Forces a top-level property to be initialized eagerly, opposed to lazily on the first access to file and/or property.
annotation class EagerInitialization
EagerInitialization
Forces a top-level property to be initialized eagerly, opposed to lazily on the first access to file and/or property. This annotation can be used as temporal migration assistance during the transition from the previous Kotlin/Native initialization scheme "eager by default" to the new one, "lazy by default".
annotation class EagerInitialization
ExperimentalAssociatedObjects
The experimental marker for associated objects API.
annotation class ExperimentalAssociatedObjects
ExperimentalContracts
This marker distinguishes the experimental contract declaration API and is used to opt-in for that feature when declaring contracts of user functions.
annotation class ExperimentalContracts
ExperimentalEncodingApi
This annotation marks the experimental API for encoding and decoding between binary data and printable ASCII character sequences.
annotation class ExperimentalEncodingApi
ExperimentalForeignApi
Marks foreign-language-related API as experimental.
annotation class ExperimentalForeignApi
ExperimentalJsCollectionsApi
This annotation marks the experimental JS-collections API that allows to manipulate with native JS-collections The API can be removed completely in any further release.
annotation class ExperimentalJsCollectionsApi
ExperimentalJsExport
Marks experimental JS export annotations.
annotation class ExperimentalJsExport
ExperimentalJsFileName
Marks experimental JsFileName annotation.
annotation class ExperimentalJsFileName
ExperimentalJsReflectionCreateInstance
This annotation marks the experimental Kotlin/JS reflection API that allows to create an instance of provided KClass The API can be removed completely in any further release.
annotation class ExperimentalJsReflectionCreateInstance
ExperimentalJsStatic
Marks the experimental JsStatic annotation.
annotation class ExperimentalJsStatic
ExperimentalMultiplatform
The experimental multiplatform support API marker.
annotation class ExperimentalMultiplatform
ExperimentalNativeApi
This annotation marks the Kotlin/Native-only standard library API that is considered experimental and is not subject to the general compatibility guarantees given for the standard library: the behavior of such API may be changed or the API may be removed completely in any further release.
annotation class ExperimentalNativeApi
ExperimentalObjCName
This annotation marks the experimental ObjCName annotation.
annotation class ExperimentalObjCName
ExperimentalObjCRefinement
This annotation marks the experimental Objective-C export refinement annotations.
annotation class ExperimentalObjCRefinement
ExperimentalPathApi
This annotation marks the extensions and top-level functions for working with java.nio.file.Path considered experimental.
annotation class ExperimentalPathApi
ExperimentalReflectionOnLambdas
This annotation marks the experimental kotlin-reflect API that allows to approximate a Kotlin lambda or a function expression instance to a KFunction instance. The behavior of this API may be changed or the API may be removed completely in any further release.
annotation class ExperimentalReflectionOnLambdas
ExperimentalStdlibApi
This annotation marks the standard library API that is considered experimental and is not subject to the general compatibility guarantees given for the standard library: the behavior of such API may be changed or the API may be removed completely in any further release.
annotation class ExperimentalStdlibApi
ExperimentalSubclassOptIn
This annotation marks the experimental preview of the language feature SubclassOptInRequired.
annotation class ExperimentalSubclassOptIn
ExperimentalTime
This annotation marks the experimental preview of the standard library API for measuring time and working with durations.
annotation class ExperimentalTime
ExperimentalTypeInference
The experimental marker for type inference augmenting annotations.
annotation class ExperimentalTypeInference
ExperimentalUnsignedTypes
Marks the API that is dependent on the experimental unsigned types, including those types themselves.
annotation class ExperimentalUnsignedTypes
ExperimentalUuidApi
This annotation marks the experimental Kotlin Uuid API.
annotation class ExperimentalUuidApi
ExportObjCClass
Makes Kotlin subclass of Objective-C class visible for runtime lookup
after Kotlin main
function gets invoked.
annotation class ExportObjCClass
ExposedCopyVisibility
In previous versions of Kotlin, the generated 'copy' method of a data class always had public visibility, even if the primary constructor was non-public. That exposed the non-public constructor of the data class.
annotation class ExposedCopyVisibility
ExtensionFunctionType
Signifies that the annotated functional type represents an extension function.
annotation class ExtensionFunctionType
ExternalObjCClass
annotation class ExternalObjCClass
FreezingIsDeprecated
Freezing API is deprecated since 1.7.20.
annotation class FreezingIsDeprecated
HiddenFromObjC
Instructs the Kotlin compiler to remove this class, function or property from the public Objective-C API.
annotation class HiddenFromObjC
HidesFromObjC
Meta-annotation that instructs the Kotlin compiler to remove the annotated class, function or property from the public Objective-C API.
annotation class HidesFromObjC
Ignore
annotation class Ignore
ImplicitlyActualizedByJvmDeclaration
This annotation marks Kotlin expect
declarations that are implicitly actualized by Java.
annotation class ImplicitlyActualizedByJvmDeclaration
InteropStubs
annotation class InteropStubs
JsExport
Exports top-level declaration on JS platform.
annotation class JsExport
JsExternalArgument
When placed on a function parameter, requires the type of the passed argument to be external.
annotation class JsExternalArgument
JsExternalInheritorsOnly
When placed on an external interface or class, requires all its child interfaces, classes, and objects to be external as well.
annotation class JsExternalInheritorsOnly
JsFileName
Specifies the name of the compiled file produced from the annotated source file instead of the default one.
annotation class JsFileName
JsModule
Denotes an external
declaration that must be imported from native JavaScript library.
annotation class JsModule
JsName
Gives a declaration (a function, a property or a class) specific name in JavaScript.
annotation class JsName
JsNonModule
Denotes an external
declaration that can be used without module system.
annotation class JsNonModule
JsQualifier
Adds prefix to external
declarations in a source file.
annotation class JsQualifier
JsStatic
Specifies that an additional static method is generated from the annotated companion object member if it's a function. If the member is a property, additional static getter/setter methods are generated.
annotation class JsStatic
JvmDefault
Specifies that a JVM default method should be generated for non-abstract Kotlin interface member.
annotation class JvmDefault
JvmDefaultWithCompatibility
Forces the compiler to generate compatibility accessors for the annotated interface in the DefaultImpls
class.
Please note that if an interface is annotated with this annotation for binary compatibility, public derived Kotlin interfaces should also be annotated with it,
because their DefaultImpls
methods will be used to access implementations from the DefaultImpls
class of the original interface.
annotation class JvmDefaultWithCompatibility
JvmDefaultWithoutCompatibility
Prevents the compiler from generating compatibility accessors for the annotated class or interface, and suppresses
any related compatibility warnings. In other words, this annotation makes the compiler generate the annotated class
or interface in the -Xjvm-default=all
mode, where only JVM default methods are generated, without DefaultImpls
.
annotation class JvmDefaultWithoutCompatibility
JvmField
Instructs the Kotlin compiler not to generate getters/setters for this property and expose it as a field.
annotation class JvmField
JvmInline
Specifies that given value class is inline class.
annotation class JvmInline
JvmMultifileClass
Instructs the Kotlin compiler to generate a multifile class with top-level functions and properties declared in this file as one of its parts. Name of the corresponding multifile class is provided by the JvmName annotation.
annotation class JvmMultifileClass
JvmName
Specifies the name for the Java class or method which is generated from this element.
annotation class JvmName
JvmOverloads
Instructs the Kotlin compiler to generate overloads for this function that substitute default parameter values.
annotation class JvmOverloads
JvmRecord
Instructs compiler to mark the class as a record and generate relevant toString/equals/hashCode methods
annotation class JvmRecord
JvmSerializableLambda
Makes the annotated lambda function implement java.io.Serializable
,
generates a pretty toString
implementation and adds reflection metadata.
annotation class JvmSerializableLambda
JvmStatic
Specifies that an additional static method needs to be generated from this element if it's a function. If this element is a property, additional static getter/setter methods should be generated.
annotation class JvmStatic
JvmSuppressWildcards
Instructs compiler to generate or omit wildcards for type arguments corresponding to parameters with
declaration-site variance, for example such as Collection<out T>
has.
annotation class JvmSuppressWildcards
JvmSynthetic
Sets ACC_SYNTHETIC
flag on the annotated target in the Java bytecode.
annotation class JvmSynthetic
JvmWildcard
Instructs compiler to generate wildcard for annotated type arguments corresponding to parameters with declaration-site variance.
annotation class JvmWildcard
Metadata
This annotation is present on any class file produced by the Kotlin compiler and is read by the compiler and reflection. Parameters have very short JVM names on purpose: these names appear in all generated class files, and we'd like to reduce their size.
annotation class Metadata
MustBeDocumented
This meta-annotation determines that an annotation is a part of public API and therefore should be included in the generated documentation for the element to which the annotation is applied.
annotation class MustBeDocumented
nativeGetter
annotation class nativeGetter
nativeInvoke
annotation class nativeInvoke
NativeRuntimeApi
This annotation marks the Kotlin/Native standard library API that tweaks or otherwise accesses the Kotlin runtime behavior.
annotation class NativeRuntimeApi
nativeSetter
annotation class nativeSetter
ObjCAction
Makes Kotlin method in Objective-C class accessible through Objective-C dispatch to be used as action sent by control in UIKit or AppKit.
annotation class ObjCAction
ObjCConstructor
annotation class ObjCConstructor
ObjCDirect
annotation class ObjCDirect
ObjCFactory
annotation class ObjCFactory
ObjCMethod
annotation class ObjCMethod
ObjCName
Instructs the Kotlin compiler to use a custom Objective-C and/or Swift name for this class, property, parameter or function.
annotation class ObjCName
ObjCOutlet
Makes Kotlin property in Objective-C class settable through Objective-C dispatch to be used as IB outlet.
annotation class ObjCOutlet
ObjCSignatureOverride
Marks functions for which Objective-C rules should be used for determinating whether two functions are conflicting.
annotation class ObjCSignatureOverride
ObsoleteNativeApi
This annotation marks the Kotlin/Native standard library API that is considered obsolete and is being phased out.
annotation class ObsoleteNativeApi
ObsoleteWorkersApi
Marks all Worker
-related API as obsolete.
annotation class ObsoleteWorkersApi
OptIn
Allows to use the API denoted by the given markers in the annotated file, declaration, or expression. If a declaration is annotated with OptIn, its usages are not required to opt in to that API.
annotation class OptIn
OptionalExpectation
Marks an expected annotation class that it isn't required to have actual counterparts in all platforms.
annotation class OptionalExpectation
OverloadResolutionByLambdaReturnType
Enables overload selection based on the type of the value returned from lambda argument.
annotation class OverloadResolutionByLambdaReturnType
ParameterName
Annotates type arguments of functional type and holds corresponding parameter name specified by the user in type declaration (if any).
annotation class ParameterName
PublishedApi
When applied to a class or a member with internal visibility allows to use it from public inline functions and makes it effectively public.
annotation class PublishedApi
PurelyImplements
Instructs the Kotlin compiler to treat annotated Java class as pure implementation of given Kotlin interface. "Pure" means here that each type parameter of class becomes non-platform type argument of that interface.
annotation class PurelyImplements
RefinesInSwift
Meta-annotation that instructs the Kotlin compiler to mark the annotated function or property as
swift_private
in the generated Objective-C API.
annotation class RefinesInSwift
Repeatable
This meta-annotation determines that an annotation is applicable twice or more on a single code element
annotation class Repeatable
ReplaceWith
Specifies a code fragment that can be used to replace a deprecated function, property or class. Tools such as IDEs can automatically apply the replacements specified through this annotation.
annotation class ReplaceWith
RequiresOptIn
Signals that the annotated annotation class is a marker of an API that requires an explicit opt-in.
annotation class RequiresOptIn
RestrictsSuspension
Classes and interfaces marked with this annotation are restricted when used as receivers for extension
suspend
functions. These suspend
extensions can only invoke other member or extension suspend
functions on this particular
receiver and are restricted from calling arbitrary suspension functions.
annotation class RestrictsSuspension
Retention
This meta-annotation determines whether an annotation is stored in binary output and visible for reflection. By default, both are true.
annotation class Retention
SharedImmutable
Note: this annotation has effect only in Kotlin/Native with legacy memory manager.
annotation class SharedImmutable
ShouldRefineInSwift
Instructs the Kotlin compiler to mark this function or property as swift_private
in the generated Objective-C API.
annotation class ShouldRefineInSwift
SinceKotlin
Specifies the first version of Kotlin where a declaration has appeared.
Using the declaration and specifying an older API version (via the -api-version
command line option) will result in an error.
annotation class SinceKotlin
Strictfp
Marks the JVM method generated from the annotated function as strictfp
, meaning that the precision
of floating point operations performed inside the method needs to be restricted in order to
achieve better portability.
annotation class Strictfp
SubclassOptInRequired
Annotation that marks open for subclassing classes and interfaces, and makes implementation and extension of such declarations as requiring an explicit opt-in.
annotation class SubclassOptInRequired
Suppress
Suppresses the given compilation warnings in the annotated element.
annotation class Suppress
SymbolName
This is a dangerous deprecated and internal annotation. Please avoid using it.
annotation class SymbolName
Synchronized
Marks the JVM method generated from the annotated function as synchronized
, meaning that the method
will be protected from concurrent execution by multiple threads by the monitor of the instance (or,
for static methods, the class) on which the method is defined.
annotation class Synchronized
annotation class Synchronized
Target
This meta-annotation indicates the kinds of code elements which are possible targets of an annotation.
annotation class Target
ThreadLocal
Marks a top level property with a backing field or an object as thread local. The object remains mutable and it is possible to change its state, but every thread will have a distinct copy of this object, so changes in one thread are not reflected in another.
annotation class ThreadLocal
Throws
This annotation indicates what exceptions should be declared by a function when compiled to a platform method in Kotlin/JVM and Kotlin/Native.
annotation class Throws
typealias Throws = Throws
Throws
This annotation indicates what exceptions should be declared by a function when compiled to a JVM method.
annotation class Throws
Transient
Marks the JVM backing field of the annotated property as transient
, meaning that it is not
part of the default serialized form of the object.
annotation class Transient
UnsafeNumber
Marker for declarations that depend on numeric types of different bit width on at least two platforms.
annotation class UnsafeNumber
UnsafeVariance
Suppresses errors about variance conflict
annotation class UnsafeVariance
Volatile
Marks the JVM backing field of the annotated var
property as volatile
, meaning that reads and writes to this field
are atomic and writes are always made visible to other threads. If another thread reads the value of this field (e.g. through its accessor),
it sees not only that value, but all side effects that led to writing that value.
annotation class Volatile
annotation class Volatile
Volatile
Marks the backing field of the annotated var
property as volatile
, meaning that reads and writes to this field
are atomic and writes are always made visible to other threads. If another thread reads the value of this field (e.g. through its accessor),
it sees not only that value, but all side effects that led to writing that value.
annotation class Volatile
typealias Volatile = Volatile