# Dokka [![official JetBrains project](https://jb.gg/badges/official.svg)](https://confluence.jetbrains.com/display/ALL/JetBrains+on+GitHub) [![TeamCity (build status)](https://teamcity.jetbrains.com/app/rest/builds/buildType:(id:Kotlin_Dokka_DokkaAntMavenGradle)/statusIcon)](https://teamcity.jetbrains.com/viewType.html?buildTypeId=Kotlin_Dokka_DokkaAntMavenGradle&branch_KotlinTools_Dokka=%3Cdefault%3E&tab=buildTypeStatusDiv)
Dokka is a documentation engine for Kotlin, performing the same function as javadoc for Java.
Just like Kotlin itself, Dokka fully supports mixed-language Java/Kotlin projects. It understands
standard Javadoc comments in Java files and [KDoc comments](https://kotlinlang.org/docs/reference/kotlin-doc.html) in Kotlin files,
and can generate documentation in multiple formats including standard Javadoc, HTML and Markdown.
## Using Dokka
**Full documentation is available at [https://kotlin.github.io/dokka/1.6.10/](https://kotlin.github.io/dokka/1.6.10/)**
### Using the Gradle plugin
_Note: If you are upgrading from 0.10.x to a current release of Dokka, please have a look at our
[migration guide](runners/gradle-plugin/MIGRATION.md)_
The preferred way is to use `plugins` block.
build.gradle.kts:
```kotlin
plugins {
id("org.jetbrains.dokka") version "1.6.10"
}
repositories {
mavenCentral()
}
```
The plugin adds `dokkaHtml`, `dokkaJavadoc`, `dokkaGfm` and `dokkaJekyll` tasks to the project.
#### Applying plugins
Dokka plugin creates Gradle configuration for each output format in the form of `dokka${format}Plugin`:
```kotlin
dependencies {
dokkaHtmlPlugin("org.jetbrains.dokka:kotlin-as-java-plugin:1.6.10")
}
```
You can also create a custom Dokka task and add plugins directly inside:
```kotlin
val customDokkaTask by creating(DokkaTask::class) {
dependencies {
plugins("org.jetbrains.dokka:kotlin-as-java-plugin:1.6.10")
}
}
```
Please note that `dokkaJavadoc` task will properly document only single `jvm` source set
To generate the documentation, use the appropriate `dokka${format}` Gradle task:
```bash
./gradlew dokkaHtml
```
Please see the [Dokka Gradle example project](https://github.com/Kotlin/dokka/tree/master/examples/gradle/dokka-gradle-example) for an example.
We encourage users to create their own plugins and share them with the community on [official plugins list](docs/src/doc/docs/community/plugins-list.md).
#### Android
Make sure you apply Dokka after `com.android.library` and `kotlin-android`.
```kotlin
buildscript {
dependencies {
classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:${kotlin_version}")
classpath("org.jetbrains.dokka:dokka-gradle-plugin:${dokka_version}")
}
}
repositories {
mavenCentral()
}
apply(plugin= "com.android.library")
apply(plugin= "kotlin-android")
apply(plugin= "org.jetbrains.dokka")
```
```kotlin
dokkaHtml.configure {
dokkaSourceSets {
named("main") {
noAndroidSdkLink.set(false)
}
}
}
```
#### Multi-module projects
For documenting Gradle multi-module projects, you can use `dokka${format}Multimodule` tasks.
```kotlin
tasks.dokkaHtmlMultiModule.configure {
outputDirectory.set(buildDir.resolve("dokkaCustomMultiModuleOutput"))
}
```
`DokkaMultiModule` depends on all Dokka tasks in the subprojects, runs them, and creates a toplevel page
with links to all generated (sub)documentations
### Using the Maven plugin
The Maven plugin does not support multi-platform projects.
Documentation is by default generated in `target/dokka`.
The following goals are provided by the plugin:
* `dokka:dokka` - generate HTML documentation in Dokka format (showing declarations in Kotlin syntax)
* `dokka:javadoc` - generate HTML documentation in Javadoc format (showing declarations in Java syntax)
* `dokka:javadocJar` - generate a .jar file with Javadoc format documentation
#### Applying plugins
You can add plugins inside the `dokkaPlugins` block:
```xml
org.jetbrains.dokka
dokka-maven-plugin
${dokka.version}
pre-site
dokka
org.jetbrains.dokka
kotlin-as-java-plugin
${dokka.version}
```
Please see the [Dokka Maven example project](https://github.com/Kotlin/dokka/tree/master/examples/maven) for an example.
### Using the Command Line
To run Dokka from the command line, download the [Dokka CLI runner](https://mvnrepository.com/artifact/org.jetbrains.dokka/dokka-cli).
To generate documentation, run the following command:
```
java -jar dokka-cli.jar
```
You can also use a JSON file with dokka configuration:
```
java -jar
```
### Output formats
Dokka documents Java classes as seen in Kotlin by default, with javadoc format being the only exception.
* `html` - HTML format used by default
* `javadoc` - looks like JDK's Javadoc, Kotlin classes are translated to Java
* `gfm` - GitHub flavored markdown
* `jekyll` - Jekyll compatible markdown
If you want to generate the documentation as seen from Java perspective, you can add the `kotlin-as-java` plugin
to the Dokka plugins classpath, eg. in Gradle:
```kotlin
dependencies{
implementation("...")
dokkaGfmPlugin("org.jetbrains.dokka:kotlin-as-java-plugin:${dokka-version}")
}
```
#### FAQ
If you encounter any problems, please see the [FAQ](https://github.com/Kotlin/dokka/wiki/faq).