Welcome to Kotlin! Some handy links:
- Kotlin Site
- Getting Started Guide
- Try Kotlin
- Kotlin Standard Library
- Issue Tracker
- Forum
- Kotlin Blog
- Follow Kotlin on Twitter
- Public Slack channel
- TeamCity CI build
In order to build Kotlin distribution you need to have:
-
Apache Ant 1.9.4 and higher
-
JDK 1.6, 1.7 and 1.8
-
Setup environment variables as following:
JAVA_HOME="path to JDK 1.8" JDK_16="path to JDK 1.6" JDK_17="path to JDK 1.7" JDK_18="path to JDK 1.8"
For local development, if you're not working on bytecode generation or the standard library, it's OK to have only JDK 8 installed, and to point all of the environment variables mentioned above to your JDK 8 installation.
Note: The JDK 6 for MacOS is not available on Oracle's site. You can download it here.
To build this project, first time you try to build you need to run this:
ant -f update_dependencies.xml
which will setup the dependencies on
intellij-core
is a part of command line compiler and contains only necessary APIs.idea-full
is a full blown IntelliJ IDEA Community Edition to be used in the plugin module.
Then, you may run Gradle to build the project and run tests, using:
./gradlew <tasks-and-options>
command on Unix/macOS, or
gradlew <tasks-and-options>
on Windows.
clean
- clean build resultsdist
- assembles the compiler distribution intodist/kotlinc/
folderideaPlugin
- assembles the Kotlin IDEA plugin distribution intodist/artifacts/Kotlin
folderinstall
- build and install all public artifacts into local maven repositoryrunIde
- build IDEA plugin and run IDEA with itcoreLibsTest
- build and run stdlib, reflect and kotlin-test testsgradlePluginsTest
- build and run gradle plugin testscompilerTest
- build and run all compiler testsideaPluginTest
- build and run all IDEA plugin tests
OPTIONAL: Some artifacts, mainly Maven plugin ones, are built separately by Maven: go into libraries
directory after building the compiler and run:
mvn install
Refer to libraries/ReadMe.md for details.
Working with the Kotlin project requires IntelliJ IDEA 2017.3. You can download an Early Access Preview version of IntelliJ IDEA 2017.3 here.
The root Kotlin project should be imported into IDEA as gradle project.
To import the project in Intellij choose project directory in Open project dialog. Then, after project opened, Select
File
-> New...
-> Module from Existing Sources
in the menu, and select build.gradle.kts
file in the project's root folder.
In the import dialog, select use default gradle wrapper
.
To be able to run tests from IntelliJ easily, check Delegate IDE build/run actions to Gradle
in the Gradle runner settings.
At this time, you can use the latest released 1.1.x version of the Kotlin plugin for working with the code. To make sure you have the latest version installed, use Tools | Kotlin | Configure Kotlin Plugin Updates and press "Check for updates now".
From this root project there are Run/Debug Configurations for running IDEA or the Compiler Tests for example; so if you want to try out the latest and greatest IDEA plugin
- VCS -> Git -> Pull
- Run the "IDEA" run configuration in the project
- a child IntelliJ IDEA with the Kotlin plugin will then startup
We love contributions! There's lots to do on Kotlin and on the standard library so why not chat with us about what you're interested in doing? Please join the #kontributors channel in our Slack chat and let us know about your plans.
If you want to find some issues to start off with, try this query which should find all Kotlin issues that marked as "up-for-grabs".
Currently only committers can assign issues to themselves so just add a comment if you're starting work on it.
A nice gentle way to contribute would be to review the standard library docs and find classes or functions which are not documented very well and submit a patch.
In particular it'd be great if all functions included a nice example of how to use it such as for the
hashMapOf()
function.
This is implemented using the @sample
macro to include code from a test function. The benefits of this approach are twofold; First, the API's documentation is improved via beneficial examples that help new users and second, the code coverage is increased.
Also the JavaScript translation could really use your help. See the JavaScript contribution section for more details.
Some of the code in the standard library is created by generating code from templates. See the README in the stdlib section for how run the code generator. The existing templates can be used as examples for creating new ones.
If you need to debug a specific generated test, ensure that you have the Working directory
in your IntelliJ run configuration set
to the root directory of this project. If you don't, every test you try to run will fail with a No such file or directory
exception.
The best way to submit a patch is to fork the project on github then send us a pull request via github.
If you create your own fork, it might help to enable rebase by default when you pull by executing
git config --global pull.rebase true
This will avoid your local repo having too many merge commits which will help keep your pull request simple and easy to apply.