Creating Web Service from Java Class-How to eliminate nillable="true"

Question

Does anyone know how to eliminate the attribute, nillable="true", from the element tags which describe the parameters in the WSDL created when creating a web service from a Java Class? It does this only for the string types. Is there something I need to set when creating the web service or before creating the web service? Or the only way is to modify this WSDL then recreate the web service from the WSDL.
example part of wsdl:
this is in the <types> tag:
<complexType name="getData">
<sequence>
<element name="schema" type="string" nillable="true"/>
<element name="table_or_view_name" type="string" nillable="true"/>
</sequence>
</complexType>
<complexType name="getDataResponse">
<sequence>
<element name="result" type="string" nillable="true"/>
</sequence>
</complexType>

Answer 1

I did do this and I got the following error when deploying to the Stand-alone OC4j:
Operation failed with error:
Error compiling
:D:\h\cots\Oracle\JDeveloper10g10.1.3\j2ee\home\applications\DBOperationsWSApp-DBData-WS\WebServices: Error instantiating compiler: webservice artifact generation failed :oracle.j2ee.ws.common.tools.api.ValidationException : Exception declaration mismatch between Implementation: dbdatapackage.DBDataOperations and Interface: dbdatapackage.DBDataWS. Impl class Method: getData declares exceptions not declared by the interface (java.lang.Exception)
I am quite sure what it is saying. It generated the code for the Interface: dbdatapackage.DVDataWS. Impl class. Why would it not do it right? What expection is it complaining about? java.lang.Exception?