Java生成XML时，换行和缩进

<pre name="code" class="java">        TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
Source xmlSource = new DOMSource(document);
ByteArrayOutputStream baos = new ByteArrayOutputStream();
Result transformResult = new StreamResult(baos);
transformer.transform(xmlSource, transformResult);