使用Java将节点添加到xml会得到意外的结果吗？

Question

This is my demo.jsp page

String filename = "TestNode.xml";
ServletContext app = getServletContext();
String projectPath = app.getRealPath("/");
String result = projectPath + filename;
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setValidating(false);
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(new FileInputStream(new File(result)));
Element rootElement = doc.getDocumentElement();
Element element1 = doc.getDocumentElement();
Element element2 = doc.createElement("hai");
rootElement.appendChild(element2);
Element name = doc.createElement("welcome");
element2.appendChild(name);
element1.appendChild(element2);
DOMSource src = new DOMSource(doc);
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = null;
transformer = transformerFactory.newTransformer();
StreamResult rslt = new StreamResult(result);
transformer.transform(src, rslt);

for this i'm getting output as:

<root>    
    <hai>
        <welcome/>
    </hai>
</root>

but expected output is:

<root>    
    <hai>
        <welcome>
        </welcome>
    </hai>
</root>

Where should I change the code to get expected result?

Answer 1

To obtain the output:

<root>    
    <hai>
        <welcome>
        </welcome>
    </hai>
</root>

Where the <welcome> </welcome> element is actually not empty but contains at least one whitespace character, you need to create a text node and add it as the child of the welcome element:

Element name = doc.createElement("welcome");

Node textNode = doc.createTextNode(" ");
name.appendChild(textNode);

element2.appendChild(name);