Rhino

Rhino is an open-source implementation of JavaScript written entirely in Java. It is typically embedded into Java applications to provide scripting to end users. It is embedded in J2SE 6 as the default Java scripting engine.

Rhino on Rails

Rhino contains

• All the features of JavaScript 1.7
• Allows direct scripting of Java
• A JavaScript shell for executing JavaScript scripts
• A JavaScript compiler to transform JavaScript source files into Java class files
• A JavaScript debugger for scripts executed with Rhino

Shell

$ java -jar js.jar
Rhino 1.7 release 1 2008 03 06
js> var now = new java.util.Date()
js> var slidesDue = java.util.Calendar.getInstance()
js> slidesDue.set(2008,3,14) // March 14? Why so early?
js> slidesDue.getTime()
Mon Apr 14 18:53:54 EDT 2008
js> slidesDue.set(2008,2,14) // What were they thinking with the date stuff, anyway?
js> slidesDue.set(2008,2,14,23,59) // let's be done by 
11:59 PM; I do have a day job
js> ((slidesDue.getTime().getTime() - now.getTime()) / 1000 / 60 / 60).toFixed(1) + " hours to go" // mix Java and JS APIs
29.1 hours to go
js> print("Huihoo Power!") // shell defines print()
Huihoo Power!

Links

• http://www.mozilla.org/rhino/
• http://docs.huihoo.com/javascript/
• http://download.huihoo.com/mozilla/rhino/
• http://docs.huihoo.com/mozilla/rhino/