Yesterday I updated Android Studio Version and Kotlin plugin version.
Android Studio Version: 3.1.2
Kotlin Version: 1.2.41
When I create an Android project using this configuration, I get Kotlin Compiler warning saying
w: /home/ganeshtikone/.gradle/caches/modules-2/files-2.1/org.jetbrains.kotlin/kotlin-stdlib-jre7/1.2.41/9e7a6f582de73d9cdc6c56ef4e23604a0ee55768/kotlin-stdlib-jre7-1.2.41.jar: kotlin-stdlib-jre7 is deprecated. Please use kotlin-stdlib-jdk7 instead
Changed as per suggestion, then I am getting following error
Unexpected inputs: ImmutableJarInput{name=org.jetbrains.kotlin:kotlin-stdlib-jre7:1.2.41, file=/home/ganeshtikone/Workspace/May-2018/fhs/app/build/intermediates/transforms/desugar/stage/debug/45.jar, contentTypes=CLASSES, scopes=EXTERNAL_LIBRARIES, status=REMOVED}
Go to Tools > Kotlin > Configure Kotlin Plugin Updates and check for updates
then in your app gradle file replace jre with jdk
implementation"org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
Important Update
Must check JDK version before setting config
Kotlin gradle config page has detailed information about this.
First of all check your kotlin version in gradle file.
if (kotlin_version == '1.2.x'
) (Use jdk
NOT jre
)
First check your jdk version in File > Project Structure.
Or check in build.gradle
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
if (jdk_version == 1.8)
implementation"org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
if (jdk_version == 1.7)
implementation"org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
if (jdk_version is < 1.7)
implementation"org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
else if(NO jdk version is set in Project Structure)
if(Android_Studio_Version < 2.2.1){
your_jdk_version = 1.7;
}
else {
your_jdk_version = 1.8;
}
Because Android Studio is bundled with jdk 1.8 since 2.2.1 version.
2. else if ( kotlin_version == '1.1.x'
) (Use jre NOT jdk)
implementation"org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version" // or jre8
Update Kotlin Version?
You can update Kotlin version from Tools > Kotlin > Configure Kotlin Updates
Something is transitively importing those libraries. Run Gradle task dependencies
to figure out what.
In my case, it was io.vertx:vertx-lang-kotlin-coroutines:3.5.1
.
If there is no update for the dependency, there is not much you can do about it
After reading Kotlin Gradle Script Topic
I find out that some ponits
If you're targeting JDK 7 or JDK 8, you can use extended versions of the Kotlin standard library which contain additional extension functions for APIs added in new JDK versions. Instead of kotlin-stdlib, use one of the following dependencies:
compile "org.jetbrains.kotlin:kotlin-stdlib-jdk7"
compile "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
I used implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8" in my project. I think it's because of compileOptions set in build.graddle
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
You must swap the codes below:
implementation"org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"
Not jre > jdk
implementation"org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"