JAXB - getting attributes from XML that not specified in XSD

Good afternoon,

In my service I have to call a downstream service whose SOAP response contains lots of attributes like

<section name="AA1">
	<grp name="..." AB1001="1.5" AB1002="..." .../>
	<grp name="..." CD1001="1.5" CD1F002="..." .../>
	...
</section>
<section name="AB1">
	<grp name="..." AB1001="1.5" AB1002="..." .../>
	<grp name="..." CD1001="1.5" CD1F002="..." .../>
	...
</section>
<section name="AB2">
	...
</section>
...

In my service's response I have to retrieve this same structure.
However as the number of the attributes are enormous so I thought I won't add all these attributes to my service's XSD but I'll go through the attributes in the response of the downstream service and whatever I'll find there will add them to my service's SOAP response.

The difficulty is that I use JAXB so Java XML beans are generated from the XSD. As the XML attributes are not in my service's XSD so somehow I should add them 'manually' (after the JAXB beans marshalled to XML (SOAP response)).

Is there a way of doing that please?

I use Spring & Spring Integration.

The outbound gateway is specified like

@Configuration
public class MppWebServiceGatewayConfig {

	...
	
	@Bean(name="serviceOutboundGateway")
	public MessageHandler serviceOutboundGateway() {
		final MarshallingWebServiceOutboundGateway gateway = new ExceptionHandlingMarshallingWebServiceOutboundGateway(url, mppMarshaller(), mppUnMarshaller());
		gateway.setMessageSender(httpPoolingWebServiceMessageSender);
		return gateway;
	}

	@Bean
	public Marshaller mppMarshaller() {
		final Jaxb2Marshaller marshaller = new Jaxb2Marshaller();
		marshaller.setContextPath(CONTEXTPATH);
		return  marshaller;
	}

	@Bean
	public Unmarshaller mppUnMarshaller() {
		final Jaxb2Marshaller unmarshaller = new Jaxb2Marshaller();
		unmarshaller.setContextPath(CONTEXTPATH);
		return  unmarshaller;
	}

	...
}

Thanks!

I might have found an answer but it is not too elegant so generally I wouldn't recommend to use it but someone might find it useful:

@EnableWs
@Configuration
public class WebServiceConfig extends CommonWsConfigurerAdapter {
...
@Override
public void addInterceptors(List<EndpointInterceptor> interceptors) {
interceptors.add(new CustomEndpointInterceptor());
}
}
@Component
class CustomEndpointInterceptor implements EndpointInterceptor {
...
@Override
public boolean handleResponse(MessageContext messageContext, Object endpoint) throws Exception {
String responseXmlString = toString(messageContext.getResponse());
Document doc = convertStringToDocument(responseXmlString);
// manipulting the response
...
// SaajSoapMessageFactory is thread safe so make sure the message factory is initialized only once
SaajSoapMessageFactory saajSoapMessageFactory = new SaajSoapMessageFactory();
saajSoapMessageFactory.afterPropertiesSet();
SaajSoapMessage saajSoapMessage = saajSoapMessageFactory.createWebServiceMessage();
saajSoapMessage.setDocument(doc);
messageContext.clearResponse();
messageContext.setResponse(saajSoapMessage);
return true;
}
...
private String toString(WebServiceMessage msg) throws IOException {
ByteArrayOutputStream out = new ByteArrayOutputStream();
msg.writeTo(out);
return new String(out.toByteArray());
}
private Document convertStringToDocument(String xmlStr) throws Exception {
// also the DocumentBuilderFactory is supposed to be thread-safe
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse( new InputSource( new StringReader( xmlStr ) ) );
return doc;
}
}