How to get all child elements of an XML file using DOM in Java?

Question

Java

Good day to all! Faced a problem, there is an xml document

document

<?xml version="1.0" encoding="utf-8"?> 
<schools> 
    <school id = "1"> 
        <class>
    <element_1>pupil_1</element_1>
    <element_2>pupil_2</element_2>
    <element_3>pupil_3</element_3>
        </class>
        <super_class>
    <element_1>super_pupil_1</element_1>
    <element_2>super_pupil_2</element_2>
    <element_3>super_pupil_3</element_3>
        </super_class>
    </school>
    <school id = "2"> 
        <class>
    <element_1>pupil_1</element_1>
    <element_2>pupil_2</element_2>
    <element_3>pupil_3</element_3>
        </class>
        <super_class>
    <element_1>super_pupil_1</element_1>
    <element_2>super_pupil_2</element_2>
    <element_3>super_pupil_3</element_3>
        </super_class>
    </school>
    <school id = "3"> 
        <class>
    <element_1>pupil_1</element_1>
    <element_2>pupil_2</element_2>
    <element_3>pupil_3</element_3>
        </class>
        <super_class>
    <element_1>super_pupil_1</element_1>
    <element_2>super_pupil_2</element_2>
    <element_3>super_pupil_3</element_3>
        </super_class>
    </school>
</schools>

from it, by school id, you need to get all the values ​​\u200b\u200bof the child elements of one school (class and super_class), I know how to get the values ​​\u200b\u200bof a separate

element

File fXmlFile = new File("demo.xml");
      DocumentBuilderFactory dbFactory = DocumentBuilderFactory
          .newInstance();
      DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
      Document doc = dBuilder.parse(fXmlFile);

      doc.getDocumentElement().normalize();

      System.out.println("Root element :"
          + doc.getDocumentElement().getNodeName());

      NodeList nList = doc.getElementsByTagName("school");

      for (int temp = 0; temp < nList.getLength(); temp++) {

        Node nNode = nList.item(temp);

        if (nNode.getNodeType() == Node.ELEMENT_NODE) {

          Element eElement = (Element) nNode;

          if (eElement.getAttribute("id").equals(findElement)) {
            System.out.println("\nCurrent Element :"
                + nNode.getNodeName());

            System.out.println("Staff id : "
                + eElement.getAttribute("id"));

            System.out.println("Class element : "
                + eElement.getElementsByTagName("class").item(0).getTextContent().trim());
            System.out.println("Super Class element : "
                + eElement.getElementsByTagName("super_class").item(0).getTextContent().trim());

        }
      }

How to get the value of both elements?
Thanks in advance!

Answer 1

I found the solution myself, what you need can be achieved using the following

code

Node el = eElement.getFirstChild();
            do {
              System.out.println(el.getTextContent());
              el = el.getNextSibling();
            } while (el != null);

I can't say anything about its aesthetics, but it works.

Answer 2

As a variant of xpath.