This Library/Interpreter is used to enable the CustomNPCs EMCAScript. If you are running the latest version of Java chances are you are already able to script NPCs once you enable EMCAScripts on the NPC. However, if you are attempting to script an NPC and it does not allow you to do so, chances are you are missing this Library/Interpreter. The details of this are listed below. I did not create this, I simply ported it to Curse for Modpack Creators. It makes it easier for creating a modpack. This is ALLOWED by terms of this Library/Interpreters licence. http://openjdk.java.net/legal/gplv2+ce.html

As per the licence requirements I have also set this project's licence to use the GNU General Public License version 2 (GPLv2)

This does not do anything on its own. Quite literally CustomNPC hooks into it and "turns on" the EMCAScript engine. If other mods implement a Nashorn Engine they will hook into this as well. Personally, I am not aware of any, but there may be some out there.

Project Nashorn

Nashorn's goal is to implement a lightweight high-performance JavaScript runtime in Java with a native JVM. This Project intends to enable Java developers embedding of JavaScript in Java applications via JSR-223 and to develop free standing JavaScript applications using the jrunscript command-line tool.

This Project is designed to take full advantage of newer technologies for native JVMs that have been made since the original development of JVM-based JavaScript which was started in 1997 by Netscape and maintained by Mozilla. This Project will be an entirely new code base, focused on these newer technologies. In particular the project will utilize the MethodHandles and InvokeDynamic APIs described in JSR-292.

Copied and pasted from https://www.curseforge.com/minecraft/mc-mods/project-nashorn, by HalestormXV. I am not the creator of this mod nor am I claiming to be the creator of this mod. All rights reserved.