Just before Devoxx, the LJC held a Nashorn HackDay in conjunction with Oracle.
With Java 8, however, Nashorn (pronounced NAS-horn, not NASH-horn) replaces Rhino (Nashorn is actually the German word for Rhino) – and Rhino is being removed.
Nashorn is a from-scratch new JS implementation, and designed to take full advantage of all Java 7 & 8 features – including method handles and invokedynamic. It is the first JS implementation to pass the spec tests 100%.
It will ship with Java 8, but it is already & pretty good shape, and with the interest in it, we decided to take it for a spin before Devoxx…
The Hackday took place at Oracle’s Moorgate building – and we were very pleased to have Attila Szegedi, one of the Oracle engineers working on Nashorn as our guide.
Attila opened the day with a presentation about how to use the JS shell (jjs) & how to integrate running Java code from within JS (and how to use Java to call out & run JS scripts from within a Java program).
In the hack sessions, people focused on using Java libraries from Java, comparing JSON processing in JS vs in Java (& some rudimentary benchmarks) with more advanced users looking at trying to defeat the Nashorn security model & sandbox.
It seemed to go very smoothly, and if there’s interest, we’d definitely be keen to run more events focused on Nashorn over the Summer – let us know if this would be interesting (leave a comment below or email us).