Running ECMAScript 5 compliant javascript on Java 7

Question

I would like to run javascript using the embedded javascript engine of Java 7. The code which I am trying to run is ECMAScript 5 compliant, which should not be a problem since the embedded Rhino's version is 1.7 release 3 which supports it. Yet, running the following snippet doesn't work:

    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("JavaScript");
    engine.eval("var char = 'a';");

It fails with the error missing variable name which indicates that char is a reserved keyword. However, the char is no longer reserved in ECMAScript 5, so I am completely confused. The question is which javascript version is supposed to work with the embedded Rhino in java 7?

I am using java 1.7.0_80, the language version reported by the engine is 1.8 and the engine version is 1.7 release 3 PRERELEASE.

Answer 1

As @RealSkeptic pointed out, the embedded script engine of OpenJDK 7 (Rhino 1.7 r4) has no problem running the above javascript snippet. It seems that Rhino 1.7 r3 can not run it, so running it using Oracle Java 7 needs the external Rhino of 1.7 r4 (or above) which can be downloaded from here. Just for completeness, the java equivalent of the code in the question based on Rhino's own API looks like this:

import org.mozilla.javascript.Context;
import org.mozilla.javascript.ScriptableObject;

public class Rhino {

    public static void main(String[] args) throws Exception {
        Context context = Context.enter();
        try {
            ScriptableObject scope = context.initStandardObjects();
            context.evaluateString(scope, "var char = 'a'", "test", 1, null);
        } finally {
             Context.exit();
        }
   }

}

Note that the import declarations are important since the same classes are available bundled in the JDK within a different package:

import sun.org.mozilla.javascript.internal.Context;
import sun.org.mozilla.javascript.internal.ScriptableObject;

Importing them yields in using the embedded engine with Rhino's API which will not work.