往xml中更新节点

/* System.out.println("2323");
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder docbuilder = factory.newDocumentBuilder();
Document parse = docbuilder
.parse(new File("src/ProdQuery.xml"));
// Element createElement2 = parse.createElement("");
Element createElement = parse.createElement("products");
Node item2 = parse.getChildNodes().item(parse.getChildNodes().getLength()-1);
for (String item : map.keySet()) {
//循环添加至products
System.out.println("tianjia1");
Element clidren = parse.createElement("product");
Attr createAttribute = parse.createAttribute("name");
createAttribute.setNodeValue(item);
Attr createAttribute2 = parse.createAttribute("value");
createAttribute2.setNodeValue(map.get(item));
clidren.setAttributeNode(createAttribute);
clidren.setAttributeNode(createAttribute2);
createElement.appendChild(clidren);
}
//将products添加到根目录
item2.appendChild(createElement);
//创建一个TransformerFactory对象
TransformerFactory tFactory = TransformerFactory.newInstance();
//得到一个操作对象
Transformer transformer = tFactory.newTransformer();
//设置们，这个是编码
transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8");
//
DOMSource source = new DOMSource(parse);
System.out.println("改变文件");
StreamResult result = new StreamResult(new File("src/ProdQuery.xml"));
//让xml文件换行
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
transformer.transform(source, result);*/