OpenJDK 9
The working forest for Nashorn for jdk9 is at http://hg.openjdk.java.net/jdk9/dev/ Nashorn repo is @ http://hg.openjdk.java.net/jdk9/dev/nashorn From the "jdk9/dev" there are routine pushes of nashorn (along with the other repos) to master forest. Build and test instructions remain the same for now. Changes specific to jdk9, if any, will be documented in future.
OpenJDK 8
The working forest The working repository for Nashorn is at http://hg.openjdk.java.net/nashorn/jdk8, but there are routine pushes of nashorn to the jdk8 tl and master repositories.
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