Kotlin Help

CLI

If for some reason you cannot use Gradle or Maven build tools, Dokka has a command line (CLI) runner for generating documentation.

In comparison, it has the same, if not more, capabilities as the Gradle plugin for Dokka. Although it is considerably more difficult to set up as there is no autoconfiguration, especially in multiplatform and multi-module environments.

Get started

The CLI runner is published to Maven Central as a separate runnable artifact.

You can find it on mvnrepository or by browsing maven central repository directories directly.

With the dokka-cli-1.7.20.jar file saved on your computer, run it with the -help option to see all available configuration options and their description:

java -jar dokka-cli-1.7.20.jar -help

It also works for some nested options, such as -sourceSet:

java -jar dokka-cli-1.7.20.jar -sourceSet -help

Generate documentation

Prerequisites

Since there is no build tool to manage dependencies, you have to provide dependency .jar files yourself.

Listed below are the dependencies that you need for any output format:

Group

Artifact

Version

Link

org.jetbrains.dokka

dokka-base

1.7.20

mvnrepository

org.jetbrains.dokka

dokka-analysis

1.7.20

mvnrepository

org.jetbrains.dokka

kotlin-analysis-compiler

1.7.20

mvnrepository

org.jetbrains.dokka

kotlin-analysis-intellij

1.7.20

mvnrepository

Below are the additional dependencies that you need for HTML output format:

Group

Artifact

Version

Link

org.jetbrains.kotlinx

kotlinx-html-jvm

0.8.0

mvnrepository

org.freemarker

freemarker

2.3.31

mvnrepository

Run with command line options

You can pass command line options to configure the CLI runner.

At the very least you need to provide the following options:

  • -pluginsClasspath - a list of absolute/relative paths to downloaded dependencies, separated by semi-colons ;

  • -sourceSet - an absolute path to code sources to generate documentation for

  • -outputDir - an absolute/relative path of the documentation output directory

java -jar dokka-cli-1.7.20.jar \ -pluginsClasspath "./dokka-base-1.7.20.jar;./dokka-analysis-1.7.20.jar;./kotlin-analysis-intellij-1.7.20.jar;./kotlin-analysis-compiler-1.7.20.jar;./kotlinx-html-jvm-0.8.0.jar;./freemarker-2.3.31.jar" \ -sourceSet "-src /home/myCoolProject/src/main/kotlin" \ -outputDir "./dokka/html"

Executing the given example generates documentation in HTML output format.

See Command line options for more configuration details.

Run with JSON configuration

It's possible to configure the CLI runner with JSON. In this case, you need to provide an absolute/relative path to the JSON configuration file as the first and only argument. All other configuration options are parsed from it.

java -jar dokka-cli-1.7.20.jar dokka-configuration.json

At the very least, you need the following JSON configuration file:

{ "outputDir": "./dokka/html", "sourceSets": [ { "sourceSetID": { "scopeId": "moduleName", "sourceSetName": "main" }, "sourceRoots": [ "/home/myCoolProject/src/main/kotlin" ] } ], "pluginsClasspath": [ "./dokka-base-1.7.20.jar", "./kotlinx-html-jvm-0.8.0.jar", "./dokka-analysis-1.7.20.jar", "./kotlin-analysis-intellij-1.7.20.jar", "./kotlin-analysis-compiler-1.7.20.jar", "./freemarker-2.3.31.jar" ] }

See JSON configuration options for more details.

Other output formats

By default, the dokka-base artifact contains the HTML output format only.

All other output formats are implemented as Dokka plugins. In order to use them, you have to put them on the plugins classpath.

For example, if you want to generate documentation in the experimental GFM output format, you need to download and pass gfm-plugin's JAR into the pluginsClasspath configuration option.

Via command line options:

java -jar dokka-cli-1.7.20.jar \ -pluginsClasspath "./dokka-base-1.7.20.jar;...;./gfm-plugin-1.7.20.jar" \ ...

Via JSON configuration:

{ ... "pluginsClasspath": [ "./dokka-base-1.7.20.jar", "...", "./gfm-plugin-1.7.20.jar" ], ... }

With the GFM plugin passed to pluginsClasspath, the CLI runner generates documentation in the GFM output format.

For more information, see Markdown and Javadoc pages.

Command line options

To see the list of all possible command line options and their detailed description, run:

java -jar dokka-cli-1.7.20.jar -help

Short summary:

Option

Description

moduleName

Name of the project/module.

moduleVersion

Documented version.

outputDir

Output directory path, ./dokka by default.

sourceSet

Configuration for a Dokka source set. Contains nested configuration options.

pluginsConfiguration

Configuration for Dokka plugins.

pluginsClasspath

List of jars with Dokka plugins and their dependencies. Accepts multiple paths separated by semicolons.

offlineMode

Whether to resolve remote files/links over network.

failOnWarning

Whether to fail documentation generation if Dokka has emitted a warning or an error.

delayTemplateSubstitution

Whether to delay substitution of some elements. Used in incremental builds of multi-module projects.

noSuppressObviousFunctions

Whether to suppress obvious functions such as those inherited from kotlin.Any and java.lang.Object.

includes

Markdown files that contain module and package documentation. Accepts multiple values separated by semicolons.

suppressInheritedMembers

Whether to suppress inherited members that aren't explicitly overridden in a given class.

globalPackageOptions

Global list of package configuration options in format "matchingRegex,-deprecated,-privateApi,+warnUndocumented,+suppress;+visibility:PUBLIC;...". Accepts multiple values separated by semicolons.

globalLinks

Global external documentation links in format {url}^{packageListUrl}. Accepts multiple values separated by ^^.

globalSrcLink

Global mapping between a source directory and a Web service for browsing the code. Accepts multiple paths separated by semicolons.

helpSourceSet

Prints help for the nested -sourceSet configuration.

loggingLevel

Logging level, possible values: DEBUG, PROGRESS, INFO, WARN, ERROR.

help, h

Usage info.

Source set options

To see the list of command line options for the nested -sourceSet configuration, run:

java -jar dokka-cli-1.7.20.jar -sourceSet -help

Short summary:

Option

Description

sourceSetName

Name of the source set.

displayName

Display name of the source set, used both internally and externally.

classpath

Classpath for analysis and interactive samples. Accepts multiple paths separated by semicolons.

src

Source code roots to be analyzed and documented. Accepts multiple paths separated by semicolons.

dependentSourceSets

Names of the dependent source sets in format moduleName/sourceSetName. Accepts multiple paths separated by semicolons.

samples

List of directories or files that contain sample functions. Accepts multiple paths separated by semicolons.

includes

Markdown files that contain module and package documentation. Accepts multiple paths separated by semicolons.

documentedVisibilities

Visibilities to be documented. Accepts multiple values separated by semicolons. Possible values: PUBLIC, PRIVATE, PROTECTED, INTERNAL, PACKAGE.

reportUndocumented

Whether to report undocumented declarations.

noSkipEmptyPackages

Whether to create pages for empty packages.

skipDeprecated

Whether to skip deprecated declarations.

jdkVersion

Version of JDK to use for linking to JDK Javadocs.

languageVersion

Language version used for setting up analysis and samples.

apiVersion

Kotlin API version used for setting up analysis and samples.

noStdlibLink

Whether to generate links to the Kotlin standard library.

noJdkLink

Whether to generate links to JDK Javadocs.

suppressedFiles

Paths to files to be suppressed. Accepts multiple paths separated by semicolons.

analysisPlatform

Platform used for setting up analysis.

perPackageOptions

List of package source set configurations in format matchingRegexp,-deprecated,-privateApi,+warnUndocumented,+suppress;.... Accepts multiple values separated by semicolons.

externalDocumentationLinks

External documentation links in format {url}^{packageListUrl}. Accepts multiple values separated by ^^.

srcLink

Mapping between a source directory and a Web service for browsing the code. Accepts multiple paths separated by semicolons.

JSON configuration

Below are some examples and detailed descriptions for each configuration section. You can also find an example with all configuration options applied at the bottom of the page.

General configuration

{ "moduleName": "Dokka Example", "moduleVersion": null, "outputDir": "./build/dokka/html", "failOnWarning": false, "suppressObviousFunctions": true, "suppressInheritedMembers": false, "offlineMode": false, "includes": [ "module.md" ], "sourceLinks": [ { "_comment": "Options are described in a separate section" } ], "perPackageOptions": [ { "_comment": "Options are described in a separate section" } ], "externalDocumentationLinks": [ { "_comment": "Options are described in a separate section" } ], "sourceSets": [ { "_comment": "Options are described in a separate section" } ], "pluginsClasspath": [ "./dokka-base-1.7.20.jar", "./kotlinx-html-jvm-0.8.0.jar", "./dokka-analysis-1.7.20.jar", "./kotlin-analysis-intellij-1.7.20.jar", "./kotlin-analysis-compiler-1.7.20.jar", "./freemarker-2.3.31.jar" ] }
moduleName

The display name used to refer to the module. It is used for the table of contents, navigation, logging, etc.

Default: root

moduleVersion

The module version.

Default: empty

outputDirectory

The directory to where documentation is generated, regardless of output format.

Default: ./dokka

failOnWarning

Whether to fail documentation generation if Dokka has emitted a warning or an error. The process waits until all errors and warnings have been emitted first.

This setting works well with reportUndocumented

Default: false

suppressObviousFunctions

Whether to suppress obvious functions.

A function is considered to be obvious if it is:

  • Inherited from kotlin.Any, Kotlin.Enum, java.lang.Object or java.lang.Enum, such as equals, hashCode, toString.

  • Synthetic (generated by the compiler) and does not have any documentation, such as dataClass.componentN or dataClass.copy.

Default: true

suppressInheritedMembers

Whether to suppress inherited members that aren't explicitly overridden in a given class.

Note: This can suppress functions such as equals/hashCode/toString, but cannot suppress synthetic functions such as dataClass.componentN and dataClass.copy. Use suppressObviousFunctions for that.

Default: false

offlineMode

Whether to resolve remote files/links over your network.

This includes package-lists used for generating external documentation links. For example, to make classes from the standard library clickable.

Setting this to true can significantly speed up build times in certain cases, but can also worsen documentation quality and user experience. For example, by not resolving class/member links from your dependencies, including the standard library.

Note: You can cache fetched files locally and provide them to Dokka as local paths. See externalDocumentationLinks section.

Default: false

includes

A list of Markdown files that contain module and package documentation.

The contents of specified files are parsed and embedded into documentation as module and package descriptions.

This can be configured on per-package basis.

sourceSets

Individual and additional configuration of Kotlin source sets.

For a list of possible options, see source set configuration.

sourceLinks

The global configuration of source links that is applied for all source sets.

For a list of possible options, see source link configuration.

perPackageOptions

The global configuration of matched packages, regardless of the source set they are in.

For a list of possible options, see per-package configuration.

externalDocumentationLinks

The global configuration of external documentation links, regardless of the source set they are used in.

For a list of possible options, see external documentation configuration.

pluginsClasspath

A list of JAR files with Dokka plugins and their dependencies.

Source set configuration

How to configure Kotlin source sets:

{ "sourceSets": [ { "displayName": "jvm", "sourceSetID": { "scopeId": "moduleName", "sourceSetName": "main" }, "dependentSourceSets": [ { "scopeId": "dependentSourceSetScopeId", "sourceSetName": "dependentSourceSetName" } ], "documentedVisibilities": ["PUBLIC", "PRIVATE", "PROTECTED", "INTERNAL", "PACKAGE"], "reportUndocumented": false, "skipEmptyPackages": true, "skipDeprecated": false, "jdkVersion": 8, "languageVersion": "1.7", "apiVersion": "1.7", "noStdlibLink": false, "noJdkLink": false, "includes": [ "module.md" ], "analysisPlatform": "jvm", "sourceRoots": [ "/home/ignat/IdeaProjects/dokka-debug-mvn/src/main/kotlin" ], "classpath": [ "libs/kotlin-stdlib-1.8.0.jar", "libs/kotlin-stdlib-common-1.8.0.jar" ], "samples": [ "samples/basic.kt" ], "suppressedFiles": [ "src/main/kotlin/org/jetbrains/dokka/Suppressed.kt" ], "sourceLinks": [ { "_comment": "Options are described in a separate section" } ], "perPackageOptions": [ { "_comment": "Options are described in a separate section" } ], "externalDocumentationLinks": [ { "_comment": "Options are described in a separate section" } ] } ] }
displayName

The display name used to refer to this source set.

The name is used both externally (for example, the source set name is visible to documentation readers) and internally (for example, for logging messages of reportUndocumented).

The platform name can be used if you don't have a better alternative.

sourceSetID

The technical ID of the source set

documentedVisibilities

The set of visibility modifiers that should be documented.

This can be used if you want to document protected/internal/private declarations, as well as if you want to exclude public declarations and only document internal API.

This can be configured on per-package basis.

Possible values:

  • PUBLIC

  • PRIVATE

  • PROTECTED

  • INTERNAL

  • PACKAGE

Default: PUBLIC

reportUndocumented

Whether to emit warnings about visible undocumented declarations, that is declarations without KDocs after they have been filtered by documentedVisibilities and other filters.

This setting works well with failOnWarning.

This can be configured on per-package basis.

Default: false

skipEmptyPackages

Whether to skip packages that contain no visible declarations after various filters have been applied.

For example, if skipDeprecated is set to true and your package contains only deprecated declarations, it is considered to be empty.

Default for CLI runner is false.

skipDeprecated

Whether to document declarations annotated with @Deprecated.

This can be configured on per-package basis.

Default: false

jdkVersion

The JDK version to use when generating external documentation links for Java types.

For example, if you use java.util.UUID in some public declaration signature, and this option is set to 8, Dokka generates an external documentation link to JDK 8 Javadocs for it.

languageVersion

The Kotlin language version used for setting up analysis and @sample environment.

apiVersion

The Kotlin API version used for setting up analysis and @sample environment.

noStdlibLink

Whether to generate external documentation links that lead to the API reference documentation of Kotlin's standard library.

Note: Links are generated when noStdLibLink is set to false.

Default: false

noJdkLink

Whether to generate external documentation links to JDK's Javadocs.

The version of JDK Javadocs is determined by the jdkVersion option.

Note: Links are generated when noJdkLink is set to false.

Default: false

includes

A list of Markdown files that contain module and package documentation.

The contents of the specified files are parsed and embedded into documentation as module and package descriptions.

analysisPlatform

Platform to be used for setting up code analysis and @sample environment.

Possible values:

  • jvm

  • common

  • js

  • native

sourceRoots

The source code roots to be analyzed and documented. Acceptable inputs are directories and individual .kt/.java files.

classpath

The classpath for analysis and interactive samples.

This is useful if some types that come from dependencies are not resolved/picked up automatically.

This option accepts both .jar and .klib files.

samples

A list of directories or files that contain sample functions which are referenced via the @sample KDoc tag.

suppressedFiles

The files to be suppressed when generating documentation.

sourceLinks

A set of parameters for source links that is applied only for this source set.

For a list of possible options, see source link configuration.

perPackageOptions

A set of parameters specific to matched packages within this source set.

For a list of possible options, see per-package configuration.

externalDocumentationLinks

A set of parameters for external documentation links that is applied only for this source set.

For a list of possible options, see external documentation configuration.

The sourceLinks configuration block allows you to add a source link to each signature that leads to the remoteUrl with a specific line number. (The line number is configurable by setting remoteLineSuffix).

This helps readers to find the source code for each declaration.

For an example, see the documentation for the count() function in kotlinx.coroutines.

You can configure source links for all source sets together at the same time, or individually:

{ "sourceLinks": [ { "localDirectory": "src/main/kotlin", "remoteUrl": "https://github.com/Kotlin/dokka/tree/master/src/main/kotlin", "remoteLineSuffix": "#L" } ] }
localDirectory

The path to the local source directory.

remoteUrl

The URL of the source code hosting service that can be accessed by documentation readers, like GitHub, GitLab, Bitbucket, etc. This URL is used to generate source code links of declarations.

remoteLineSuffix

The suffix used to append the source code line number to the URL. This helps readers navigate not only to the file, but to the specific line number of the declaration.

The number itself is appended to the specified suffix. For example, if this option is set to #L and the line number is 10, the resulting URL suffix is #L10.

Suffixes used by popular services:

  • GitHub: #L

  • GitLab: #L

  • Bitbucket: #lines-

Default: empty (no suffix)

Per-package configuration

The perPackageOptions configuration block allows setting some options for specific packages matched by matchingRegex.

You can add package configurations for all source sets together at the same time, or individually:

{ "perPackageOptions": [ { "matchingRegex": ".*internal.*", "suppress": false, "skipDeprecated": false, "reportUndocumented": false, "documentedVisibilities": ["PUBLIC", "PRIVATE", "PROTECTED", "INTERNAL", "PACKAGE"] } ] }
matchingRegex

The regular expression that is used to match the package.

suppress

Whether this package should be skipped when generating documentation.

Default: false

skipDeprecated

Whether to document declarations annotated with @Deprecated.

This can be set on project/module level.

Default: false

reportUndocumented

Whether to emit warnings about visible undocumented declarations, that is declarations without KDocs after they have been filtered by documentedVisibilities and other filters.

This setting works well with failOnWarning.

This can be configured on source set level.

Default: false

documentedVisibilities

The set of visibility modifiers that should be documented.

This can be used if you want to document protected/internal/private declarations within this package, as well as if you want to exclude public declarations and only document internal API.

Can be configured on source set level.

Default: PUBLIC

External documentation configuration

The externalDocumentationLink block allows the creation of links that lead to the externally hosted documentation of your dependencies.

For example, if you are using types from kotlinx.serialization, by default they are unclickable in your documentation, as if they are unresolved. However, since the API reference documentation for kotlinx.serialization is built by Dokka and is published on kotlinlang.org, you can configure external documentation links for it. Thus allowing Dokka to generate links for types from the library, making them resolve successfully and clickable.

You can configure external documentation links for all source sets together at the same time, or individually:

{ "externalDocumentationLinks": [ { "url": "https://kotlinlang.org/api/kotlinx.serialization/", "packageListUrl": "https://kotlinlang.org/api/kotlinx.serialization/package-list" } ] }
url

The root URL of documentation to link to. It must contain a trailing slash.

Dokka does its best to automatically find package-list for the given URL, and link declarations together.

If automatic resolution fails or if you want to use locally cached files instead, consider setting the packageListUrl option.

packageListUrl

The exact location of a package-list. This is an alternative to relying on Dokka automatically resolving it.

Package lists contain information about the documentation and the project itself, such as module and package names.

This can also be a locally cached file to avoid network calls.

Complete configuration

Below you can see all possible configuration options applied at the same time.

{ "moduleName": "Dokka Example", "moduleVersion": null, "outputDir": "./build/dokka/html", "failOnWarning": false, "suppressObviousFunctions": true, "suppressInheritedMembers": false, "offlineMode": false, "sourceLinks": [ { "localDirectory": "src/main/kotlin", "remoteUrl": "https://github.com/Kotlin/dokka/tree/master/src/main/kotlin", "remoteLineSuffix": "#L" } ], "externalDocumentationLinks": [ { "url": "https://docs.oracle.com/javase/8/docs/api/", "packageListUrl": "https://docs.oracle.com/javase/8/docs/api/package-list" }, { "url": "https://kotlinlang.org/api/latest/jvm/stdlib/", "packageListUrl": "https://kotlinlang.org/api/latest/jvm/stdlib/package-list" } ], "perPackageOptions": [ { "matchingRegex": ".*internal.*", "suppress": false, "reportUndocumented": false, "skipDeprecated": false, "documentedVisibilities": ["PUBLIC", "PRIVATE", "PROTECTED", "INTERNAL", "PACKAGE"] } ], "sourceSets": [ { "displayName": "jvm", "sourceSetID": { "scopeId": "moduleName", "sourceSetName": "main" }, "dependentSourceSets": [ { "scopeId": "dependentSourceSetScopeId", "sourceSetName": "dependentSourceSetName" } ], "documentedVisibilities": ["PUBLIC", "PRIVATE", "PROTECTED", "INTERNAL", "PACKAGE"], "reportUndocumented": false, "skipEmptyPackages": true, "skipDeprecated": false, "jdkVersion": 8, "languageVersion": "1.7", "apiVersion": "1.7", "noStdlibLink": false, "noJdkLink": false, "includes": [ "module.md" ], "analysisPlatform": "jvm", "sourceRoots": [ "/home/ignat/IdeaProjects/dokka-debug-mvn/src/main/kotlin" ], "classpath": [ "libs/kotlin-stdlib-1.8.0.jar", "libs/kotlin-stdlib-common-1.8.0.jar" ], "samples": [ "samples/basic.kt" ], "suppressedFiles": [ "src/main/kotlin/org/jetbrains/dokka/Suppressed.kt" ], "sourceLinks": [ { "localDirectory": "src/main/kotlin", "remoteUrl": "https://github.com/Kotlin/dokka/tree/master/src/main/kotlin", "remoteLineSuffix": "#L" } ], "externalDocumentationLinks": [ { "url": "https://docs.oracle.com/javase/8/docs/api/", "packageListUrl": "https://docs.oracle.com/javase/8/docs/api/package-list" }, { "url": "https://kotlinlang.org/api/latest/jvm/stdlib/", "packageListUrl": "https://kotlinlang.org/api/latest/jvm/stdlib/package-list" } ], "perPackageOptions": [ { "matchingRegex": ".*internal.*", "suppress": false, "reportUndocumented": false, "skipDeprecated": false, "documentedVisibilities": ["PUBLIC", "PRIVATE", "PROTECTED", "INTERNAL", "PACKAGE"] } ] } ], "pluginsClasspath": [ "./dokka-base-1.7.20.jar", "./kotlinx-html-jvm-0.8.0.jar", "./dokka-analysis-1.7.20.jar", "./kotlin-analysis-intellij-1.7.20.jar", "./kotlin-analysis-compiler-1.7.20.jar", "./freemarker-2.3.31.jar" ], "pluginsConfiguration": [ { "fqPluginName": "org.jetbrains.dokka.base.DokkaBase", "serializationFormat": "JSON", "values": "{\"separateInheritedMembers\":false,\"footerMessage\":\"© 2021 pretty good Copyright\"}" } ], "includes": [ "module.md" ] }

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Last modified: 27 January 2023