//J+
xc.setXPath(xpath);
HelperNodeList nl = new HelperNodeList();
nl.appendChild(doc.createTextNode("\n"));
nl.appendChild(xc.getElement());
nl.appendChild(doc.createTextNode("\n"));
transforms.addTransform(Transforms.TRANSFORM_XPATH, nl);
transforms.addTransform(Transforms.TRANSFORM_C14N_WITH_COMMENTS);
sig.addDocument("", transforms, Constants.ALGO_ID_DIGEST_SHA1);