[Java] Creare file XML

[BigNick]

Ciao a tutti,
ho realizzato il seguente codice Java per la creazione di un file XML

import java.io.File;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
 
import org.w3c.dom.Document;
import org.w3c.dom.Element;

public class XML 
{
public static void main(String[] args) { 
	  try {		  	
			DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
			DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
	 
			Document doc = docBuilder.newDocument();
			Element rootElement = doc.createElement("cd");
			doc.appendChild(rootElement);
	 
			Element cdrom = doc.createElement("cd-rom");
			rootElement.appendChild(cdrom);
	 
			Element title = doc.createElement("title");
			title.appendChild(doc.createTextNode("prova"));
			cdrom.appendChild(title);
	 
			TransformerFactory transformerFactory = TransformerFactory.newInstance();
			Transformer transformer = transformerFactory.newTransformer();
			DOMSource source = new DOMSource(doc);
			StreamResult result = new StreamResult(new File("cd.xml"));
	 	 
			transformer.transform(source, result);
	 
			System.out.println("File salvato!");
	 
		  } catch (ParserConfigurationException e) {
			e.printStackTrace();
		  } catch (TransformerException e) {
			e.printStackTrace();
		  }

    } 

}

Questo codice mi crea il seguente file XML

<?xml version="1.0" encoding="UTF-8" standalone="no"?><cd><cd-rom><title>prova</title></cd-rom></cd>

Vorrei sapere come posso aggiungere il DTD prima della ROOT <cd>???
Grazie a tutti in anticipio