libraries/scripting/src/docs/scripting.txt

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[[scripting, Scripting Library]]
= Scripting =

[devstatus]
--------------
source=libraries/scripting/dev-status.xml
--------------

The Scripting Library allows Mixin methods to be implemented in any JSR-223 scripting language, loaded dynamically on
first use and allowing reloading of the script in runtime.

include::../../build/docs/buildinfo/artifact.txt[]

The Scripting Library is a Generic mixin class that implements
Composite interfaces by delegating to script functions using Java Scripting API. All Java Scripting API (JSR-223)
implementations that support

[source,java]
----
    ((javax.script.Invocable) scriptEngine).invokeFunction( functionName, arguments );
----

should be supported. On Java.Net there is a https://java.net/projects/scripting/sources/svn/show/trunk/engines[list of Java Scripting API languages].


It is important to understand that the ScriptEngines must be present on the classpath, or they will not be available,
with the exception of JavaScript which uses the built-in Nashorn engine.

We welcome additional information and samples of languages that has been tried and tested.

.Language Support
[options="header"]
|=======
|Language | Supported | Tested | License | Implementation
|JavaScript | Yes | Yes | ? |Nashorn, built-in Java 8 and later
|Groovy | Yes | Yes |Apache |Apache Groovy
|Ruby | Yes | No |(EPL\|GPL\|LGPL) + Ruby |JRuby
|Python | Yes | No |https://opensource.org/licenses/Python-2.0[Python] |Jython, must use jython-standalone
|Kotlin | Yes | No |Apache |Jetbrains
|Lua | Yes | No |MIT |luaj.org,
|Clojure | Yes | No |CPL |https://github.com/pmf/clojure-jsr223
|=======

The following languages may or may not be supported, and was found at https://java.net/projects/scripting/sources/svn/show/trunk/engines[Java.Net Scripting project]

.Potential Languages
[options="header"]
|=======
| Language | Location | License
|beanshell | |
|ejs | |
|freemarker |https://freemarker.apache.org | Apache
|jacl | |
|jaskell |https://github.com/MarchLiu/jaskell | MIT
|jawk | |
|jelly | |Apache
|jep | |
|jexl |https://commons.apache.org/jexl/ | Apache
|jst | |
|judo | |
|juel | |
|ognl |https://commons.apache.org/ognl/ | Apache
|pnuts | |
|scheme |http://sisc-scheme.org/ | (MPLv1.1|GPLv2)
|velocity |https://velocity.apache.org | Apache
|xpath | |
|xslt | |
|=======

.Not Compatible Languages
[options="header"]
|=======
| Language | Comment
| Java | Implementation exists at https://github.com/nickman/javax-scripting/ which is forked from https://java.net/projects/scripting. It doesn't support Invocable, and additional work on ScriptMixin is required to support this. Alternatively, fork the ScriptEngine implementation and support Invocable in it.
|=======

include::../../../../libraries/scripting/src/docs/javascript.txt[]

include::../../../../libraries/scripting/src/docs/groovy.txt[]