On Jun 19, 4:49 pm, Mike Tardif <[EMAIL PROTECTED]> wrote:
> On Jun 19, 11:33 am, Norris Boyd <[EMAIL PROTECTED]> wrote:
>
>
>
> > On Jun 19, 10:36 am, Mike Tardif <[EMAIL PROTECTED]> wrote:
>
> > > On Jun 18, 8:28 pm, Norris Boyd <[EMAIL PROTECTED]> wrote:
>
> > > > On Jun 18, 4:57 pm, Mike Tardif <[EMAIL PROTECTED]> wrote:
>
> > > > > Hi Again
>
> > > > > I've exposed my objects (whose properties are dynamic) to JavaScript
> > > > > by deriving from ScriptableObject and generally all is good.
>
> > > > > But I've failed to properly deal with this JavaScript scenario:
> > > > > try {
> > > > > myObject.notMyProperty = "hello"
> > > > > }
> > > > > catch(e) {
> > > > > "unrecognized property"
> > > > > }
> > > > > "hello world"
>
> > > > > My question is: in myObject's put(String, Scriptable, Object) method,
> > > > > what kind of RhinoException do I throw when myObject recognizes that
> > > > > notMyProperty is invalid, so that catch block in the above script gets
> > > > > executed as well as any code that follows.
>
> > > > > I wish the docs for Scriptable and/or ScriptableObject would expand a
> > > > > bit more on exception handling.
>
> > > > Standard JavaScript behavior is that assignment to an undefined
> > > > property results in creation of the property. That means that I didn't
> > > > define a standard exception for failures. What kind of failure are you
> > > > wanting to throw an exception for?
>
> > > > --Norris
>
> > > Thanks for the quick reply. I should have added that I'm trying to
> > > emulate this script behaviour
> > > that is running on two other JS engines. The designer of "myObj"
> > > spec'ed it out to throw on undefined
> > > properties. Is there any way to trick Rhino into throwing?
> > > Scriptable.has() apparently gets called before a put (the docs say a
> > > set). Maybe that's the approach I should take.
>
> > That's fine, Java objects behave this way when accessed from
> > JavaScript. Probably the easiest thing to do is to throw a
> > WrappedException constructed with a Java exception type that you
> > define.
>
> > --N
>
> I had tried that originally, without success. I've re-tried, with
> ditto results. Throwing a WrappedException or any other kind of
> RhinoException in ScriptableObject.put() kicks me out of
> Script.exec(Context, Scriptable) without executing the JS catch block
> and any code that follows.
>
> Do I need to derive any thing in particular from SciptableObject to
> make this happens?
>
> PS: I'm using version 1.6.5
I want to retract my previous posting. Throwing a WrappedException
inside the put method does generate a JavaScript exception which is
then caught in the aforementioned script. To illustrate:
public class MyObject extends ScriptableObject {
...
public void put(String name, Scriptable start, Object value) {
if (name.equals("notMyProperty"))
throw new WrappedException(new Exception("property
'notMyProperty' unknown.")));
super.put(name, start, value);
}
}
works fine. Another scoping bug originally led me to believe
otherwise.
Thank you for your help.
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