if (parts.length>0) {
XMLStreamReader reader = msg.readPayload();
XMLStreamReaderUtil.verifyTag(reader,wrapperName);
Object wrapperBean = wrapper.unmarshal(reader, (msg.getAttachments() != null) ?
new AttachmentUnmarshallerImpl(msg.getAttachments()): null);
try {
for (PartBuilder part : parts) {
Object o = part.readResponse(args,wrapperBean);
// there's only at most one ResponseBuilder that returns a value.