# How can I publish a javadoc.jar file with my Kotlin multiplatform project?

**URL:** <https://discuss.kotlinlang.org/t/how-can-i-publish-a-javadoc-jar-file-with-my-kotlin-multiplatform-project/21119>\
**Category:** Multiplatform\
**Created:** [March 7, 2021, 5:10pm UTC](https://discuss.kotlinlang.org/t/how-can-i-publish-a-javadoc-jar-file-with-my-kotlin-multiplatform-project/21119 "2021-03-07T17:10:50Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![marcoeckstein](https://avatars.discourse-cdn.com/v4/letter/m/87869e/32.png) [@marcoeckstein](https://discuss.kotlinlang.org/u/marcoeckstein)\
**Post date:** [March 7, 2021, 5:10pm UTC](https://discuss.kotlinlang.org/t/how-can-i-publish-a-javadoc-jar-file-with-my-kotlin-multiplatform-project/21119/1 "2021-03-07T17:10:50Z")

</div>

_ **Note:** I have posted [this question at Stack Overflow](https://stackoverflow.com/questions/66512540/) already, but I want to increase my chances of getting a reply for this niche topic by posting here. If you want credit, please reply over there._

_ **Related topics/issues:** _  
_- [How to configure Dokka for kotlin-multiplatform](https://discuss.kotlinlang.org/t/how-to-configure-dokka-for-kotlin-multiplatform/9834)_  
_- [Dokka Javadoc plugin currently does not support generating documentation for multiplatform project](https://github.com/Kotlin/dokka/issues/1753)_

I am trying to publish [my Kotlin multiplatform library](https://github.com/marco-eckstein/kotlin-lib) to [Maven Central via Sonatype](https://oss.sonatype.org/). This repository requires me to include a `javadoc.jar` file with my artifacts. Unfortunately, the IntelliJ IDEA project wizard and the [Kotlin multiplatform docs](https://kotlinlang.org/docs/multiplatform.html) do not help me do that. When running the Gradle task `dokkaJavadoc` (for the official Kotlin documentation tool Dokka), I get the error “Dokka Javadoc plugin currently does not support generating documentation for multiplatform project.”

I actually do not need genuine JavaDocs for publishing - an empty `javadoc.jar` or one with other docs generated by Dokka would suffice. Since I have been a longtime Maven user and these are my first steps with Gradle, I have no idea how to do that.

`build.gradle.kts`:

```kotlin
plugins {
    kotlin("multiplatform") version "1.4.31"
    id("org.jlleitschuh.gradle.ktlint") version "10.0.0"
    id("io.gitlab.arturbosch.detekt") version "1.15.0"
    id("org.jetbrains.dokka") version "1.4.20"
    id("maven-publish")
    signing
}

group = "com.marcoeckstein"
version = "0.0.3-SNAPSHOT"

publishing {
    publications {
        create<MavenPublication>("maven") {
            pom {
                val projectGitUrl = "https://github.com/marco-eckstein/kotlin-lib"
                name.set(rootProject.name)
                description.set(
                    "A general-purpose multiplatform library. " +
                        "Implemented in Kotlin, usable also from Java, JavaScript and more."
                )
                url.set(projectGitUrl)
                inceptionYear.set("2021")
                licenses {
                    license {
                        name.set("MIT")
                        url.set("https://opensource.org/licenses/MIT")
                    }
                }
                developers {
                    developer {
                        id.set("marcoeckstein.com")
                        name.set("Marco Eckstein")
                        email.set("marco.eckstein@gmx.de")
                        url.set("https://www.marcoeckstein.com")
                    }
                }
                issueManagement {
                    system.set("GitHub")
                    url.set("$projectGitUrl/issues")
                }
                scm {
                    connection.set("scm:git:$projectGitUrl")
                    developerConnection.set("scm:git:$projectGitUrl")
                    url.set(projectGitUrl)
                }
            }
        }
    }
    repositories {
        maven {
            name = "sonatypeStaging"
            url = uri("https://oss.sonatype.org/service/local/staging/deploy/maven2")
            credentials(PasswordCredentials::class)
        }
    }
}

signing {
    useGpgCmd()
    sign(publishing.publications["maven"])
}

repositories {
    mavenCentral()
    jcenter()
}

kotlin {
    targets.all {
        compilations.all {
            kotlinOptions {
                allWarningsAsErrors = true
            }
        }
    }
    jvm {
        compilations.all {
            kotlinOptions.jvmTarget = "11"
        }
        testRuns["test"].executionTask.configure {
            useJUnitPlatform()
        }
    }
    js(BOTH) {
        browser {
            testTask {
                useKarma {
                    useChromeHeadless()
                    webpackConfig.cssSupport.enabled = true
                }
            }
        }
    }
    val hostOs = System.getProperty("os.name")
    val isMingwX64 = hostOs.startsWith("Windows")
    val nativeTarget = when {
        hostOs == "Mac OS X" -> macosX64("native")
        hostOs == "Linux" -> linuxX64("native")
        isMingwX64 -> mingwX64("native")
        else -> throw GradleException("Host OS is not supported in Kotlin/Native.")
    }

    sourceSets {
        val commonMain by getting
        val commonTest by getting {
            dependencies {
                implementation(kotlin("test-common"))
                implementation(kotlin("test-annotations-common"))
                implementation("io.kotest:kotest-assertions-core:4.4.1")
            }
        }
        val jvmMain by getting
        val jvmTest by getting {
            dependencies {
                implementation(kotlin("test-junit5"))
                implementation("org.junit.jupiter:junit-jupiter-api:5.6.0")
                runtimeOnly("org.junit.jupiter:junit-jupiter-engine:5.6.0")
            }
        }
        val jsMain by getting
        val jsTest by getting {
            dependencies {
                implementation(kotlin("test-js"))
            }
        }
        val nativeMain by getting
        val nativeTest by getting
    }
}

configure<org.jlleitschuh.gradle.ktlint.KtlintExtension> {
    enableExperimentalRules.set(true)
    verbose.set(true)
    // ktlint.disabled_rules:
    // filename:
    // Caught more precisely (with desired exceptions) with detekt.
    // import-ordering:
    // ktlint's order is not supported (yet) by IntelliJ.
    // See:
    // - https://github.com/pinterest/ktlint/issues/527
    // - https://youtrack.jetbrains.com/issue/KT-10974
    // no-wildcard-imports:
    // Not desired. We want them for Java statics and Enum members.
    // experimental:annotation:
    // Not desired.
    // experimental:multiline-if-else:
    // Not desired.
    disabledRules.set(
        setOf(
            "filename",
            "import-ordering",
            "no-wildcard-imports",
            "experimental:annotation",
            "experimental:multiline-if-else"
        )
    )
    additionalEditorconfigFile.set(file("$projectDir/.editorconfig"))
}

detekt {
    input = files("$projectDir/src/")
    config = files("$projectDir/detekt-config.yml")
    buildUponDefaultConfig = true
}

tasks {
    withType<io.gitlab.arturbosch.detekt.Detekt> {
        // Target version of the generated JVM bytecode. It is used for type resolution.
        jvmTarget = "11"
    }
}

```

---

<div class="post-metadata">

**Author:** ![kyay10](https://avatars.discourse-cdn.com/v4/letter/k/c57346/32.png) [@kyay10](https://discuss.kotlinlang.org/u/kyay10)\
**Post date:** [March 7, 2021, 5:24pm UTC](https://discuss.kotlinlang.org/t/how-can-i-publish-a-javadoc-jar-file-with-my-kotlin-multiplatform-project/21119/2 "2021-03-07T17:24:41Z")

</div>

might something as simple as:

```auto
java {
    withJavadocJar()
}

```

suffice?

---

<div class="post-metadata">

**Author:** ![Lamba92\_v2](https://sea1.discourse-cdn.com/flex019/user_avatar/discuss.kotlinlang.org/lamba92_v2/32/8387_2.png) [@Lamba92\_v2](https://discuss.kotlinlang.org/u/Lamba92_v2)\
**Post date:** [March 7, 2021, 9:23pm UTC](https://discuss.kotlinlang.org/t/how-can-i-publish-a-javadoc-jar-file-with-my-kotlin-multiplatform-project/21119/3 "2021-03-07T21:23:06Z")

</div>

Yeah I was facing this issue few days ago for [kotlingram](https://github.com/lamba92/kotlingram/) and in the end I literally put the same Dokka HTML in each publication and it works!

Have a look [here](https://github.com/lamba92/kotlingram/blob/master/buildSrc/src/main/kotlin/com/github/lamba92/kotlingram/gradle/KotlingramPlugin.kt) how I’ve done it!

---

<div class="post-metadata">

**Author:** ![marcoeckstein](https://avatars.discourse-cdn.com/v4/letter/m/87869e/32.png) [@marcoeckstein](https://discuss.kotlinlang.org/u/marcoeckstein)\
**Post date:** [March 19, 2021, 5:55pm UTC](https://discuss.kotlinlang.org/t/how-can-i-publish-a-javadoc-jar-file-with-my-kotlin-multiplatform-project/21119/4 "2021-03-19T17:55:48Z")

</div>

No. I get the error “SourceSet with name ‘main’ not found.”

---

<div class="post-metadata">

**Author:** ![marcoeckstein](https://avatars.discourse-cdn.com/v4/letter/m/87869e/32.png) [@marcoeckstein](https://discuss.kotlinlang.org/u/marcoeckstein)\
**Post date:** [March 19, 2021, 8:01pm UTC](https://discuss.kotlinlang.org/t/how-can-i-publish-a-javadoc-jar-file-with-my-kotlin-multiplatform-project/21119/5 "2021-03-19T20:01:39Z")

</div>

Thanks a lot! I noticed I had another issue related to publishing, but given your code I could resolve all publishing-related issues:

```kotlin
plugins {
    kotlin("multiplatform") version "1.4.31"
    id("org.jlleitschuh.gradle.ktlint") version "10.0.0"
    id("io.gitlab.arturbosch.detekt") version "1.15.0"
    id("org.jetbrains.dokka") version "1.4.20"
    id("maven-publish")
    signing
}

group = "com.marcoeckstein"
version = "0.0.3"

val dokkaHtml by tasks.getting(org.jetbrains.dokka.gradle.DokkaTask::class)

val javadocJar: TaskProvider<Jar> by tasks.registering(Jar::class) {
    dependsOn(dokkaHtml)
    archiveClassifier.set("javadoc")
    from(dokkaHtml.outputDirectory)
}

publishing {
    publications.withType<MavenPublication> {
        artifact(javadocJar)
        pom {
            val projectGitUrl = "https://github.com/marco-eckstein/kotlin-lib"
            name.set(rootProject.name)
            description.set(
                "A general-purpose multiplatform library. " +
                    "Implemented in Kotlin, usable also from Java, JavaScript and more."
            )
            url.set(projectGitUrl)
            inceptionYear.set("2021")
            licenses {
                license {
                    name.set("MIT")
                    url.set("https://opensource.org/licenses/MIT")
                }
            }
            developers {
                developer {
                    id.set("marcoeckstein.com")
                    name.set("Marco Eckstein")
                    email.set("marco.eckstein@gmx.de")
                    url.set("https://www.marcoeckstein.com")
                }
            }
            issueManagement {
                system.set("GitHub")
                url.set("$projectGitUrl/issues")
            }
            scm {
                connection.set("scm:git:$projectGitUrl")
                developerConnection.set("scm:git:$projectGitUrl")
                url.set(projectGitUrl)
            }
        }
        the<SigningExtension>().sign(this)
    }
    repositories {
        maven {
            name = "sonatypeStaging"
            url = uri("https://oss.sonatype.org/service/local/staging/deploy/maven2")
            credentials(PasswordCredentials::class)
        }
    }
}

signing {
    useGpgCmd()
}

repositories {
    mavenCentral()
    jcenter()
}

kotlin {
    targets.all {
        compilations.all {
            kotlinOptions {
                allWarningsAsErrors = true
            }
        }
    }
    jvm {
        compilations.all {
            kotlinOptions.jvmTarget = "11"
        }
        testRuns["test"].executionTask.configure {
            useJUnitPlatform()
        }
    }
    js(BOTH) {
        browser {
            testTask {
                useKarma {
                    useChromeHeadless()
                    webpackConfig.cssSupport.enabled = true
                }
            }
        }
    }
    val hostOs = System.getProperty("os.name")
    val isMingwX64 = hostOs.startsWith("Windows")
    val nativeTarget = when {
        hostOs == "Mac OS X" -> macosX64("native")
        hostOs == "Linux" -> linuxX64("native")
        isMingwX64 -> mingwX64("native")
        else -> throw GradleException("Host OS is not supported in Kotlin/Native.")
    }

    sourceSets {
        val commonMain by getting
        val commonTest by getting {
            dependencies {
                implementation(kotlin("test-common"))
                implementation(kotlin("test-annotations-common"))
                implementation("io.kotest:kotest-assertions-core:4.4.1")
            }
        }
        val jvmMain by getting
        val jvmTest by getting {
            dependencies {
                implementation(kotlin("test-junit5"))
                implementation("org.junit.jupiter:junit-jupiter-api:5.6.0")
                runtimeOnly("org.junit.jupiter:junit-jupiter-engine:5.6.0")
            }
        }
        val jsMain by getting
        val jsTest by getting {
            dependencies {
                implementation(kotlin("test-js"))
            }
        }
        val nativeMain by getting
        val nativeTest by getting
    }
}

configure<org.jlleitschuh.gradle.ktlint.KtlintExtension> {
    enableExperimentalRules.set(true)
    verbose.set(true)
    // ktlint.disabled_rules:
    // filename:
    // Caught more precisely (with desired exceptions) with detekt.
    // import-ordering:
    // ktlint's order is not supported (yet) by IntelliJ.
    // See:
    // - https://github.com/pinterest/ktlint/issues/527
    // - https://youtrack.jetbrains.com/issue/KT-10974
    // no-wildcard-imports:
    // Not desired. We want them for Java statics and Enum members.
    // experimental:annotation:
    // Not desired.
    // experimental:multiline-if-else:
    // Not desired.
    disabledRules.set(
        setOf(
            "filename",
            "import-ordering",
            "no-wildcard-imports",
            "experimental:annotation",
            "experimental:multiline-if-else"
        )
    )
    additionalEditorconfigFile.set(file("$projectDir/.editorconfig"))
}

detekt {
    input = files("$projectDir/src/")
    config = files("$projectDir/detekt-config.yml")
    buildUponDefaultConfig = true
}

tasks {
    withType<io.gitlab.arturbosch.detekt.Detekt> {
        // Target version of the generated JVM bytecode. It is used for type resolution.
        jvmTarget = "11"
    }
}

```