Kotlin plugin

There are currently two Kotlin plugins.

JetBrains Kotlin plugin

Donated by JetBreains.

Original URL: https://github.com/JetBrains/kotlin-netbeans

It can be found inside contrib folder of Apache NetBeans source code:

https://github.com/JetBrains/kotlin-netbeans/issues/137

https://github.com/apache/netbeans/pull/1398

Steps to build it:

1. The pom.xml requires some dependencies that are not in the central maven repository. These are: asm-all.jar, idea-formatter.jar, intellij-core.jar, kotlin-converter.jar, kotlin-formatter.jar, kotlin-ide-common.jar, openapi-formatter.jar.  intellij-core.jar artifact could be directly taken from: https://www.jetbrains.com/intellij-repository/releases. The other artifacts can be found at https://github.com/JetBrains/kotlin-eclipse project inside the kotlin-bundled-compiler folder. Once you have collected all these libraries, create a lib folder inside kotlin-netbeans project and paste them inside there.
2. In NetBeans, click on Tools → Plugins → Settings tab and add a new plugin Portal: Name: NetBeans 8.2 Plugin Portal, URL: http://updates.netbeans.org/netbeans/updates/8.2/uc/final/distribution/catalog.xml.gz. Make it active.

However, the plugin contains Kotlin code that needs to be built/migrated to the latest Kotlin compiler version. Anyone fluent in Kotlin is welcome to work with Ioannis to do that.

However, NetBeans 12.x already provides some basic support via java/kotlin.editor module. One can open a .kt file via the Windows→Favourites tab.

It uses Kotlin.tmLanguage.json. This JavaDoc explains how to integrate a TextMate lexer with NetBeans.

There are also contrib/groovy.grails and contrib/groovy.grailsproject.