How to count the depth of xml document (DOM example)

To get the depth of a XML, just loop the node recursively, and compare the level, that’s all.Here is a DOM parser example to count and show the deepest level of an XML file.

1. XML File

<company> 
        <staff id="1">
                <firstname>yong</firstname>
                <lastname>mook kim</lastname>
                <nickname>mkyong</nickname>
                <salary>1000000</salary>
                <age>29</age>
		<extra>
			<test>123</test>
		</extra>
        </staff>
        <staff id="2">
                <firstname>low</firstname>
                <lastname>yin fong</lastname>
                <nickname>fong fong</nickname>
                <salary>500000</salary>
        </staff>
</company>

2. Java & DOM example

package com.mkyong;
import java.io.IOException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
public class XMLUtil {
  static int depthOfXML = 1;
  public static void main(String argv[]) {
    try {
	String filepath = "/users/mkyong/test.xml";
	DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
	DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
	Document doc = docBuilder.parse(filepath);
	Element elements = doc.getDocumentElement();
	int level = 1;
	System.out.println(elements.getNodeName() + "[" + level + "]");
	NodeList nodeList = elements.getChildNodes();
	printNode(nodeList, level);
	System.out.println("The deepest level is : " + depthOfXML);
    } catch (ParserConfigurationException pce) {
	pce.printStackTrace();
    } catch (IOException ioe) {
	ioe.printStackTrace();
    } catch (SAXException sae) {
	sae.printStackTrace();
  private static void printNode(NodeList nodeList, int level) {
	level++;
	if (nodeList != null && nodeList.getLength() > 0) {
	  for (int i = 0; i < nodeList.getLength(); i++) {
		Node node = nodeList.item(i);
		if (node.getNodeType() == Node.ELEMENT_NODE) {
			System.out.println(node.getNodeName() + "[" + level + "]");
			printNode(node.getChildNodes(), level);
			// how depth is it?
			if (level > depthOfXML) {
				depthOfXML = level;

Output

company[1]
staff[2]
firstname[3]
lastname[3]
nickname[3]
salary[3]
age[3]
extra[3]
test[4]
staff[2]
firstname[3]
lastname[3]
nickname[3]
salary[3]
The deepest level is : 4

References

1. How To Count XML Elements In Java – (DOM Parser)
2. How To Read XML File In Java – (DOM Parser)