java解析xml文件，返回xml字符串

public static String toStringFromDoc(Document document) {
String result = null;

if (document != null) {
StringWriter strWtr = new StringWriter();
StreamResult strResult = new StreamResult(strWtr);
TransformerFactory tfac = TransformerFactory.newInstance();
try {
javax.xml.transform.Transformer t = tfac.newTransformer();
t.setOutputProperty(OutputKeys.ENCODING, "UTF-16");
t.setOutputProperty(OutputKeys.INDENT, "yes");
t.setOutputProperty(OutputKeys.METHOD, "xml"); // xml, html,
// text
t.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
t.transform(new DOMSource(document.getDocumentElement()), strResult);
} catch (Exception e) {
System.err.println("XML.toString(Document): " + e);
}
result = strResult.getWriter().toString();
try {
strWtr.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return result;
}

public static void main(String[] args) {
URL url = ImitateService.class.getClassLoader().getResource("/In.xml");
String file = url.getFile();
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
try {
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(file);
String xml = toStringFromDoc(doc);
LogUtil.info(xml);
} catch (Exception e) {
e.printStackTrace();
}
}