kotlin.jvm.JvmDefault.kt Maven / Gradle / Ivy
/*
* Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
* Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
*/
package kotlin.jvm
import kotlin.internal.RequireKotlin
import kotlin.internal.RequireKotlinVersionKind
/**
*
* Specifies that a JVM default method should be generated for non-abstract Kotlin interface member.
*
* Usages of this annotation require an explicit compilation argument to be specified:
* either `-Xjvm-default=enable` or `-Xjvm-default=compatibility`.
*
* * with `-Xjvm-default=enable`, only default method in interface is generated for each @[JvmDefault] method.
* In this mode, annotating an existing method with @[JvmDefault] can break binary compatibility, because it will effectively
* remove the method from the `DefaultImpls` class.
* * with `-Xjvm-default=compatibility`, in addition to the default interface method, a compatibility accessor is generated
* in the `DefaultImpls` class, that calls the default interface method via a synthetic accessor.
* In this mode, annotating an existing method with @[JvmDefault] is binary compatible, but results in more methods in bytecode.
*
* Removing this annotation from an interface member is a binary incompatible change in both modes.
*
* Generation of default methods is only possible with JVM target bytecode version 1.8 (`-jvm-target 1.8`) or higher.
*
* @[JvmDefault] methods are excluded from interface delegation.
*/
@SinceKotlin("1.2")
@RequireKotlin("1.2.40", versionKind = RequireKotlinVersionKind.COMPILER_VERSION)
@Target(AnnotationTarget.FUNCTION, AnnotationTarget.PROPERTY)
@Deprecated("Switch to new -Xjvm-default modes: `all` or `all-compatibility`")
annotation class JvmDefault
/**
* 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`.
*
* Annotating an existing class with this annotation is a binary incompatible change. Therefore this annotation makes
* the most sense for _new_ classes in libraries which opted into the compatibility mode.
*
* Used only with `-Xjvm-default=compatibility|all-compatibility`.
*/
@SinceKotlin("1.4")
@RequireKotlin("1.4", versionKind = RequireKotlinVersionKind.COMPILER_VERSION)
@Target(AnnotationTarget.CLASS)
annotation class JvmDefaultWithoutCompatibility