signed xml does no more contain:

[Fabio Mondelli]

Hello,
I want to sign and verify xml files.

in my case, the signed file does not contain the first line: <?xml 
version="1.0" encoding="UTF-8"?> from the original document.

what could be the reason? Im doing a enveloped xml signature.

here is the code:

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
            dbf.setNamespaceAware(true);
            DocumentBuilder db = dbf.newDocumentBuilder();
            Document doc = 
db.parse(parameterObject.getUnsignedInputXMLFile());
            String BaseURI = 
parameterObject.getSignedXMLFile().toURL().toString();
            XMLSignature sig = new XMLSignature(doc, BaseURI, 
XMLSignature.ALGO_ID_SIGNATURE_RSA_SHA1);
...


            Element rootElement = doc.getDocumentElement();
            rootElement.insertBefore(sig.getElement(), 
rootElement.getFirstChild());
            sig.addResourceResolver(new OfflineResolver());
            Transforms transforms = new Transforms(doc);

transforms.addTransform(Transforms.TRANSFORM_ENVELOPED_SIGNATURE);
transforms.addTransform(Transforms.TRANSFORM_C14N_WITH_COMMENTS);

thank U!