Nashorn

Nashorn replaces Rhino as the default JavaScript engine for the Oracle JVM. Nashorn is much faster since it uses the invokedynamic feature of the JVM. It also includes a command line tool (jjs).

jjs

JDK 8 includes the command line tool jjs for running JavaScript.

We can run JavaScript files from the command line (assuming we have Java 8’s bin in our PATH) in the following manner:

$ jjs script.js

Try running jjs in the terminal below:

This can be useful for running scripts. For example, let’s say we wanted to quickly find the sum of some numbers.

var data = [1, 3, 5, 7, 11]
var sum = data.reduce(function(x, y) {return x + y}, 0)
print(sum)

Try running the code above. Our first command in the terminal should be jjs, followed by the code given. It should print out “27”.

Type exit() to move out of the jjs command window. ...