Encoding missing from XML header

Question

I have to manipulate an XML document. Using Java 1.4.1, I build a Document object based on the XML file, manipulate the Document and output it as attached below.
The problem is that the xml header in the output does not contain the "encoding" information. I could of course manipulate the output afterwards, but it would not be a neat solution. Any ideas?
DOMSource domSource = new DOMSource(document);
  StreamResult streamResult = new StreamResult(
       new OutputStreamWriter(System.out , java.nio.charset.Charset.forName("UTF-8"))
  TransformerFactory tf = TransformerFactory.newInstance();
  Transformer serializer = tf.newTransformer();
  serializer.transform(domSource, streamResult);

Answer 1

When you serialize your output to a Writer, the parser has no way to tell what encoding the Writer uses, so it's up to you to ensure that the parser knows what encoding the Writer is using. Otherwise it will not specify any encoding, essentially assuming the Writer is using either UTF-8 or UTF-16 encodings.
In your case you don't have a problem, because "no encoding" means that the document is encoded in UTF-8 or UTF-16; it's easy for a parser to examine the first few bytes of the file and tell which it is. Yours is encoded in UTF-8, so it's correct.