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Hey im having some trouble configuring the kotlin compile java version using the kotlin dsl for grad...
# gradle
v
Hey im having some trouble configuring the kotlin compile java version using the kotlin dsl for gradle. I cant seem to find 
kotlinOptions
. Im using gradle version 6.5
s
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tasks.withType<KotlinCompile> {
    kotlinOptions.jvmTarget = "1.8"
}
v
I tried this but get 
unresolved reference KotlinCompile
any idea what would cause that?
I tried
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import org.jetbrains.kotlin.gradle.tasks.KotlinCompile
but had the same issue
o
do you have the kotlin plugin applied?
☝️ 1
v
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plugins {
    `kotlin-dsl`
}
do you mean this or do you mean the android studio plugin?
o
I mean like 
kotlin("jvm")
you might need to specify a version, 
kotlin("jvm") version "1.3.72"
v
oh... did not have that. Didnt realize I needed that haha
been compiling fine without it. My bad!
wait I already have 
kotlin("android")
do I need 
kotlin("jvm")
with it?
o
I don't think so
v
ok then im not sure what my issue is... 🤔
o
they all use the same underlying JAR, which has mutliple declared plugins in it
s
Kotlin for Android doesn't allow setting the java version afaik. You're stuck with 1.6
That, or it is possible, just through a different method
v
uh im not sure thats true. Android supports java 1.8
I think you are capped at 1.8 afaik
o
looks like it routes differently
v
hmm what do you mean?
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kotlinOptions {
    jvmTarget = "1.8"
  }
this is what im trying to accomplish
o
it's nested in the 
android
block, not configured via tasks
v
yes I tried in that block also 🤔
s
Give me a minute
👍 1
v
it cant find 
kotlinOptions
I see this issue but they said its fixed in gradle 5.6... Im on gradle 6.5 and its not working
but even the workaround is not working
ok so I think I just needed
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implementation(kotlin("gradle-plugin", version = "1.3.72"))
I still cant use 
kotlinOptions
but at least I can configure the 
KotlinCompile
task
o
that's pretty weird, considering that the source of 
kotlin("android")
is that plugin I think
v
really? wtf...
let me post my exact code
o
v
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class AndroidLibraryCommon : Plugin<Project> {

    override fun apply(target: Project) {
        target.plugins.apply("com.android.library")
        target.plugins.apply("kotlin-android")
        target.plugins.apply("kotlin-android-extensions")

        target.extensions.getByType<LibraryExtension>().configure()
    }

    private fun LibraryExtension.configure() {
        compileSdkVersion(...
ok sorry for the weird formatting
s
v
could it be because its a custom plugin?
o
if it's a custom plugin, you need to add the gradle-plugin to the classpath of the plugin too
v
how do I do that?
o
which means yes, 
implementation(kotlin("gradle-plugin", version = "1.3.72"))
but in your 
dependencies
block, not nested in 
buildscript
v
ok weird. why can I still not reference 
kotlinCompile
though?
o
generated accessors don't work in plugins
v
oh wait ya my bad
o
also, if you have 
kotlin("android")
in your plugin's buildscript, I don't think that's very useful
considering the plugin itself is not an android project
v
ok second somewhat unrelated question. I have a setup where I have a 
Dependencies.kt
file with a 
KOTLIN_VERSION
constant. Do you know if theres a way to reference that from within the 
buildSrc/build.gradle.kts
? I seem to only be able to reference it from other build files
kotlin("android")
is being applied to the plugins 
AndroidLibrary
extension
o
no, I'm pretty sure 
buildSrc/build.gradle.kts
(and settings too) cannot access any declared files that need to be compiled, since you need the 
build.gradle.kts
to define how to build them
you might be able to get away with applying a common 
Dependencies.kts
though? I'm not sure how that works out
v
hmm ok. do you know of a way to share the kotlin version between those gradle files then?
o
well, the 
buildSrc
stuff is usually compiled against 
embeddedKotlinVersion
(defined by Gradle) since it is used by the Gradle build, not your project
so in practice I don't find that I need to declare the same kotlin version, because that is technically incorrect
v
oh I see
man this gets confusing lol
o
yes, a little bit
v
do I have to specify version for that dependency then?
for the 
gradle-plugin
dependency
o
I don't think so
v
ok cool. thanks so much for the help
o
hmm, let me dig up one of my projects to double check
it's a weird balance you need to do 🙂
v
been trying to make a custom plugin so I can share build files between modules
tooons of boiler plate if you have a lot of modules (in android)
o
so my plugin declares 
compileOnly(kotlin("gradle-plugin"))
-- that is, it uses the embedded version for compiling against, but does not enforce it on the end build, and does not provide a specific version there
then the actual build is free to use e.g. 1.4-M3 instead
v
Ohhh I see. That's a good idea. I'll change it to that
hey stupid question but if I put this under the 
buildscript { dependencies {
block as suggested here: https://kotlinlang.org/docs/reference/using-gradle.html then it doesnt work
I have to put it under the normal dependency block as 
implementation
otherwise 
KotlinCompile
cant be found. Any ideas as to why the difference from what the gradle docs show?
o
that's because you're making a plugin, not writing it in the 
build.gradle.kts
buildscript
is for the `build.gradle.kts`'s classpath
v
oh I see. man this gradle stuff is hard to keep track of lol. thanks for the help
does that get included in the actual apk as as dependency then? or just for the 
buildSrc
module?
o
your plugin resides on your project's 
build.gradle.kts
classpath, not on the compile classpath
so it won't get included anywhere
v
isnt anything included using 
implementation
the compile classpath?
o
it's in the 
buildSrc
compile classpath for sure, but not your main project
assuming you're writing it in 
buildSrc/build.gradle.kts
v
ya ok that makes sense... I guess im just still slightly confused when to use 
implementation
vs 
classpath
o
classpath
is always for when you need a class in the 
build.gradle.kts
you're currently in, it's only valid inside of 
buildscript { dependenices {} }
implementation
is for when you need to compile against a class, regardless of if that is for a plugin or for an application
v
I have 
classpath(kotlin("gradle-plugin"))
in my projects 
build.gradle.kts
(not buildSrc) If I have it in the buildSrc as well, is it redundant to have it both places?
ok I think that makes sense, im just not totally sure what is shared between BuildSrc and the rest of the modules
o
anything in buildSrc's runtime classpath is added to the classpath of the buildscripts in other modules
I think that declaring 
kotlin("gradle-plugin")
in both places as a dependency is redundant
v
ok wow this makes way more sense now. Thanks you so much for the help
o
however I'm not 100% sure if you might also need to declare the one in 
buildSrc
as 
api
instead, so that it appears on the compile classpath of the main 
build.gradle.kts
try it and see 😛
v
ill try it out!
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