There are a whole lot of JSR-223 script engines available at https://scripting.dev.java.net/ (scroll down to the bottom and you see the 25 or so languages supported). These use a BSD license which is Apache friendly (see http://people.apache.org/~cliffs/3party.html<http://people.apache.org/%7Ecliffs/3party.html>), so AFAIK is ok to distribute these in an Apache project all we'd need to do is include the Sun copyright and BSD license in the NOTICE file.
One problem with them is the engines are compiled with JDK6 so don't work with JDK 1.4 or 1.5, and I think we need to keep BSF3 working on JDK 1.4 if we can. One way around this is Retroweaver ( http://retroweaver.sourceforge.net/) which uses byte code manipulate to convert compiled classes to be JDK 1.4 compatible. To see if this is feasible I've added a module to the build to download that scripting engine zip, unzip it, convert an engine to JDK 1.4 with Retroweaver, and install the new jar in the local maven repo. See https://svn.apache.org/repos/asf/jakarta/bsf/trunk/bsf3/install-engines/. It seems to work, so what do people think about using these engines in BSF3? It would certainly expedite things but it feels a bit odd doing this, what do you think? ...ant so one option would be to just use those and not implement any of those existing engines in BSF. One problem with that is i think those engines are compiled with JDK6 (i've not checked, read that on a mailing list),
