How to use a custom marshaller in spring WS - marshalling

Question

I created a SOAP Webservice using spring-ws.
Here is my config Class :
#EnableWs
#Configuration
public class EmutationSOAPConfig extends WsConfigurerAdapter {
#Autowired
LoggingInterceptor loggingInterceptor;
#Bean
public ServletRegistrationBean messageDispatcherServlet(ApplicationContext applicationContext) {
MessageDispatcherServlet servlet = new MessageDispatcherServlet();
servlet.setApplicationContext(applicationContext);
return new ServletRegistrationBean(servlet, "/ws/*");
}
#Bean(name="emutationService")
public Wsdl11Definition defaultWsdl11Definition() {
SimpleWsdl11Definition wsdl11Definition = new SimpleWsdl11Definition();
wsdl11Definition.setWsdl(new ClassPathResource("/wsdl/emutation-fc1.wsdl"));
return wsdl11Definition;
}
// ....
}
And here is my EndPoint class :
#Endpoint
public class EmutationServiceEndpoint {
#PayloadRoot(namespace = NAMESPACE_URI, localPart = "ConsultationFibres" )
#ResponsePayload
public ConsultationFibresResponse consultationFibres(#RequestPayload ConsultationFibres request) throws SoapFaultClientException, EmutationDefaultFaultMessage, EmutationTechnicalFaultMessage {
ObjectFactory factory = new ObjectFactory();
ConsultationFibresResponse response =factory.createConsultationFibresResponse();
// ....
return response;
}
}
the types ConsultationFibresResponse and ConsultationFibres were generated from a WSDL that cannot be changed.
here is the WSDL part that describe ConsultationFibres :
<xsd:element name="ConsultationFibres">
<xsd:complexType>
<xsd:sequence>
<!-- .... -->
<xsd:element minOccurs="0" name="offset" type="xsd:int"/>
<xsd:element minOccurs="0" name="limit" type="xsd:int"/>
</xsd:sequence>
</xsd:complexType>
</xsd:element>
the problem is that the elements offset and limit are unmarshalled as 0 when they are empty in xml SOAP request :
<ns2:offset></ns2:offset>
<ns2:limit></ns2:limit>
i want them to be null instead without modifying the WSDL or the generated classes.
I want to use the javax.xml.bind.annotation.adapters.XmlAdapter to define how to define how to convert string to integer.
but i don't know how to override the marshaller/unlarshaller used by spring.
please help me.