How to update xml files in java

Question

I have a xml file call data.xml like the code below. The project can run from client side no problem and it can read the xml file. The problem I have now is I I want to writ

Answer 1

Start by loading the XML file...

DocumentBuilderFactory f = DocumentBuilderFactory.newInstance();
DocumentBuilder b = f.newDocumentBuilder();
Document doc = b.parse(new File("Data.xml"));

Now, there are a few ways to do this, but simply, you can use the xpath API to find the nodes you want and update their content

XPath xPath = XPathFactory.newInstance().newXPath();
Node startDateNode = (Node) xPath.compile("/data/startdate").evaluate(doc, XPathConstants.NODE);
startDateNode.setTextContent("29/07/2015");

xPath = XPathFactory.newInstance().newXPath();
Node endDateNode = (Node) xPath.compile("/data/enddate").evaluate(doc, XPathConstants.NODE);
endDateNode.setTextContent("29/07/2015");

Then save the Document back to the file...

Transformer tf = TransformerFactory.newInstance().newTransformer();
tf.setOutputProperty(OutputKeys.INDENT, "yes");
tf.setOutputProperty(OutputKeys.METHOD, "xml");
tf.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");

DOMSource domSource = new DOMSource(doc);
StreamResult sr = new StreamResult(new File("Data.xml"));
tf.transform(domSource, sr);