Subj : Re: null to jsFunction_ with Integer parameter is 0
To   : Trinition
From : Igor Bukanov
Date : Tue Feb 01 2005 11:36 am

Trinition wrote:
> I have a ScriptableObject with a function:
> 
> jsFunction_setBgcolor(Integer color) {
> ....
> }
> 
> Originally, this function took an int.  However, I wanted to be able to
> support 'null' to indicate no color (i.e. transparent).  Thus, I
> changed it to take an Integer instead of an int.
> 
> However, Rhino is passing in an Integer with the value 0 when I invoke
> it with a script like this:
> 
> myObject.setBgcolor(null);
> 
> Is there a way to get Rhino to pass me a null instead of a new
> Integer(0)?

Rhino treats int and Integer in the same way when calling methods in 
ScriptableObject subclasses which is a feature so if you really want to 
distingush between null and non-null arguments, change the argument type 
from Integer to Object to have:

jsFunction_setBgcolor(Object color) {
     if (color == null) {
         ....
     } else {
         int value = ((Integer)Context.toType(color, 
Integer.TYPE)).intVaue();
         ...
     }
}

And if you would like to treat undefined values in the same as null, 
change the above to:
     if (color == null || color == Contxt.getUndefinedValue()) {
     ...

Regards, Igor

.