Three questions about Java Scripting API.

Guys,
here are three questions about java scripting api, please help.

(1) How can I get all the variables created inside my engine?
There are two kinds of variables: first kind is Java objects that I have put inside the engine, and second kind is the variables created inside my script, such as 'var a = 4;'. How can I list all the variables of that two kinds, or at least the second kind?

(2) Is there is a way to make 'import static' to the engine? I dont want to write MyClass.MyEnum.MyEnumItem inside my script every time. Also, I cannot put the whole enum into the engine with engine.put("MyEnum", MyEnum); I can put only enum items separately: engine.put("MyEnum", MyEnum.EnumItemA);. Thats why I ask about static import.

(3) How can I cast engine variables back to java variables inside my java code?
Here is my example:

package mypackage; import java.util.ArrayList; import java.util.List; import javax.script.ScriptEngine; import javax.script.ScriptEngineFactory; import javax.script.ScriptEngineManager; public class Main { public static void main(String[] args) throws Exception { ScriptEngineManager mgr = new ScriptEngineManager(); List<ScriptEngineFactory> factories = mgr.getEngineFactories(); ScriptEngineManager factory = new ScriptEngineManager(); ScriptEngine engine = factory.getEngineByName("JavaScript"); ArrayList<Double> myList = new ArrayList<Double>(); myList.add(5.0); engine.put("MyList", myList); engine.eval("MyVar = MyList.get(0);"); System.out.println((Double)engine.get("MyVar")); } }

The result is:

Exception in thread "main" java.lang.ClassCastException: sun.org.mozilla.javascript.internal.NativeJavaObject cannot be cast to java.lang.Double
at mypackage.Main.main(Main.java:28)

Is it possible to retrieve my Double java object from the engine?