Re: JSF-RI disallows custom String (and Object) converters?

From: Adam Winer <>
Date: Tue, 09 Aug 2005 09:52:48 -0700


You can create a custom converter and manually attach
it to components, but we can't really allow custom
String and Object converters.

For starters, Application.createConverter(Class) throws
an exception if nothing is registered - so we'd have
to wrap UIInput.getConverterWithType() with
"try/catch (FacesException e)" - which would be
brutal for performance, since a common scenario would
result in a thrown exception.

-- Adam

Mike Kienenberger wrote:
> I notice that the JSF-RI disallows custom String (and Object) converters.
> Inside the private method UIInput.getConverterWithType(FacesContext context),
> // if converterType is null, String, or Object, assume no
> conversion is needed
> I don't see anything mentioned in the spec or javadocs that requires
> this restriction.
> Does this limitation have to followed in all JSF-compliant
> implementations? (I originally brought this up on the MyFaces dev
> list, but was told that Myfaces had to follow the JSF-RI behavior for
> compatibility.)
> My use case is that I would like to create a java.lang.String
> converter that automatically converts all empty strings to null.
> Thanks!
> -Mike Kienenberger
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