Value not set to model for f:selectItem itemValue=" "/

Question

I have a selectOneChoice which value is bound to a String property in backing bean. I select among several one-character values, single space is one of them. The original value is null. When I select the single space option, it is not set to the backing bean. When I select some other option, it works. When I subsequently set the space option, it works.
Is this bug or feature? I work it around by setting a dummy property with special value, that will be mapped to the original one as a space.
Viliam

Answer 1

I've found the culprit, it is method isEmpty in oracle.adf.view.faces.component.UIXEditableValue, here is the decompiled code:
    protected boolean isEmpty(Object value) {
        if(value == null) return true;
        else return (value instanceof String) && ((String)value).trim().length() == 0;
    }The logic to treat space-only strings as empty is good for some (maybe many) applications, but surely it is not the general case.
There is another workaround to use <h:selectOneMenu> tag instead, if you can.
Viliam