ByteArrayOutputStream out = new ByteArrayOutputStream();
Canonicalizer canonicalizer = new Canonicalizer(out,
Canonicalizer.EXCLUSIVE_XML_CANONICALIZATION_WITH_COMMENTS);
Document doc = new Document(pdu);
canonicalizer.write(doc.query("//* | //namespace::node()"));
byte[] result = out.toByteArray();
out.close();
String s = new String(out.toByteArray(), "UTF8");
assertEquals(expected, s);