nilable and validate()

["Samuel B. Quiring" <sb...@Cayuse.com>]

Greetings,

I have a schema fragment that looks like this:

<xs:complexType name="HumanNameDataType">
    <xs:sequence>
         <xs:element name="PrefixName" type="glob:StringMin1Max10Type" minOccurs="0"/>
         <xs:element name="FirstName" type="glob:StringMin1Max35Type"/>
         <xs:element name="MiddleName" type="glob:StringMin1Max25Type" minOccurs="0"/>
         <xs:element name="LastName" type="glob:StringMin1Max60Type"/>
         <xs:element name="SuffixName" type="glob:StringMin1Max10Type" minOccurs="0"/>
    </xs:sequence>
</xs:complexType>

I'm calling validate() to verify the java object after I fill it with values.  For the three fields with minOccurs="0", if I set value to null validate returns this error:

validation error: <xml-fragment xmlns:glob="http://apply.grants.gov/system/GlobalLibrary-V1.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
    <glob:PrefixName>Dr.</glob:PrefixName>
    <glob:FirstName>Emmet</glob:FirstName>
    <glob:MiddleName>T</glob:MiddleName>
    <glob:LastName>Brown</glob:LastName>
    <glob:SuffixName xsi:nil="true"/>
</xml-fragment>,com.cayuse.db.model.rr.sf424.DPDPIContactInfo@a9ae05
object=com.cayuse.db.model.rr.sf424.DPDPIContactInfo@a9ae05
validationerror: error: cvc-elt.3.1: Element has xsi:nil attribute but is not nillable

To deal with this I tried setting the value 3 different ways:

name.setSuffixName(null);   -- see above error
name.setSuffixName("");     -- min string length must be 1
do nothing                  -- this works.

Only if I did nothing did validate() report no errors.

What is the difference between setting a value to null and not setting a value at all?  Is there a configuration parameter I can use to say "setting a value to null is the same as not setting it?"

Is this behavior documented somewhere?  I searched the docs but couldn't find anything, but I probably missed it.

-Sam