How to deal with optional elements?

Question

Hi,
I'm using clientgen to generate the client classes required for me to access a web service from an EJB. The web services is document-oriented and thus I just assemble the message by building up ordinary Java objects (which were generated by clientgen).
SIDStructure s = new SIDStructure();
                    s.setSIDUniqueReference(createUniqueRef(findCriteriaTO));     s.setSIDOtherCriteria(createSIDOther(findCriteriaTO));
where createUniqueRef and createSIDOther create the necessary objects to assign to the setters on the SIDStructure object.
If I comment out the s.setSIDUniqueReference(..) line above, the XML sent over the wire is as follows:
<SIDSearchCriteria>
..<SIDUniqueReference xsi:nil="true"/>
..<SIDOtherCriteria>
....<FamilyName>smith</FamilyName>
..<SIDOtherCriteria>
..</SIDSearchCriteria>
</SIDSearchCriteria>
But this doesn't conform to my schema. The schema says:
<xs:complexType name="SIDSearchCriteriaStructure">
..<xs:sequence>
....<xs:choice>
......<xs:element ref="SIDUniqueReference"/>
......<xs:element ref="SIDOtherCriteria"/>
....</xs:choice>
..</xs:sequence>
</xs:complexType>
So my question is, how can I get WebLogic to not output an element for a field in the client classes that isn't set? i.e. I don't want it to send the element <SIDUniqueReference xsi:nil="true"/> over the wire.
Thanks
Nick
Message was edited by:
nasmith

Answer 1

After speaking to BEA support it appears as though there is a partial solution to this issue. If you add the attributes minOccurs="0" nillable="true" to the elements then the SOAP message is correct. i.e.
<xs:complexType name="SIDSearchCriteriaStructure">
<xs:sequence>
<xs:choice>
<xs:element ref="SIDUniqueReference" minOccurs="0" nillable="true"/>
<xs:element ref="SIDOtherCriteria" minOccurs="0" nillable="true"/>
</xs:choice>
</xs:sequence>
</xs:complexType>
I say that this is only a partial fix because elements cannot have minOccurs and nillable attribtes when they are references (as opposed to named elements - e.g. <xs:element name="SIDDNA" type="RestrictedStringType"/>). This is according to XMLSpy anyway. Don't know whether it's W3C legal though.
Nick