首先，构造一个document对象：
Document doc = null;
try {
doc = DocumentBuilderFactory.newInstance()
.newDocumentBuilder().newDocument();
} catch (ParserConfigurationException e) {
e.printStackTrace();
return null;
} 然后，在doc中加入需要的节点，例如：
Element register = doc.createElement("Register");
register.setAttribute("id",REGISTER_ATTRIB_ID);
register.setAttribute("type",REGISTER_ATTRIB_TYPE);
doc.appendChild(register);
Element params = doc.createElement("Params");
register.appendChild(params);
Element item = doc.createElement(tagName);
item.appendChild(doc.createTextNode(textNode));
params.appendChild(item);
最后，将document对象转换成字符串
：
public static String convertDocToString(Document doc,String propertyName,String progertyValue){
Transformer transformer = null;
try {
transformer = TransformerFactory.newInstance().newTransformer();
} catch (TransformerConfigurationException e) {
e.printStackTrace();
return null;
} catch (TransformerFactoryConfigurationError e) {
e.printStackTrace();
return null;
}
transformer.setOutputProperty(propertyName,progertyValue);
DOMSource domSource = new DOMSource(doc);
StreamResult streamResult = new StreamResult();
ByteArrayOutputStream os = new ByteArrayOutputStream();
streamResult.setOutputStream(os);
try {
transformer.transform(domSource,streamResult);
} catch (TransformerException e) {
e.printStackTrace();
return null;
} finally {
try {
os.flush();
os.close();
} catch (Exception e2) {
e2.printStackTrace();
}
}
return os.toString();
}