DynJS: an ECMAScript (JavaScript) runtime for the JVM

From the DynJS website:

DynJS comes with a binary that you can use to execute Javascript files on the command line.

DynJS can be embedded into an existing Java application to provide JavaScript scripting abilities from your Java projects.

Command Line

$ ./bin/dynjs --help
Usage: dynjs [--console |--debug | --help | --version |FILE]
Starts the dynjs console or executes FILENAME depending the parameters

 FILE      : File to be executed by dynjs
 --console : Opens a REPL console to test small expressions.
 --debug   : Run REPL in debug mode.
 --help    : Shows current screen. Running without parameters also shows this.
 --version : Shows current dynjs version.

$ cat my_app.js
print("Hi! What's your name?");
var sayHello = function(name) {
    print("Hello " + name);
}

System = java.lang.System;
scanner = new java.util.Scanner(System.in);
name = scanner.nextLine();
sayHello(name);

$ ./bin/dynjs my_app.js
Hi! What's your name?
Douglas
Hello Douglas
^D

Embedding

import org.dynjs.Config;
import org.dynjs.exception.ThrowException;
import org.dynjs.runtime.*;

public class ScriptRunner {
  DynJS dynjs;
  Config config;

  public ScriptRunner() {
    config = new Config();
    dynjs  = new DynJS(config);
  }

  public Object runScript(String fileName) {
    Runner runner = dynjs.newRunner();
    return runner.withSource(new File(fileName)).execute();
  }

  public Object eval(String code) {
    return dynjs.evaluate(code);
  }

}

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