Question

I have a simple XML, and I want to get the attributes. There are a few examples on the web, but I still dont understand why I get 17 when I see only 4. I even try to count locations where I think text could be, but still I don’t get that number unless is the length of the output . Which leads me to not know how to get the attribute name of all Tag3.

<?xml version="1.0" encoding="UTF-8"?>
<tag1 xmlns="something">
    <xxxxxx-Set>
        <tag3 Name="a"/>
        <tag3 Name="b"/>
        <tag3 Name="c"/>
        <tag3 Name="d"/>
    </xxxxxx-Set>
    <tagB>
        <tag3 Name="a"/>
        <tag3 Name="b"/>
        <tag3 Name="c"/>
        <tag3 Name="d"/>
    </tagB>
</tag1>

This is my java code:

import java.io.File;
import java.util.Arrays;
import java.util.List;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;


public class ParseXML {


    public static void main(String[] args) {
        try {

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

            NodeList tagAs= doc.getElementsByTagName("xxxxxx-Set").item(0).getChildNodes(); //should be all the tag3 elements?

            for(int i = 0; i < tagAs.getLength(); i++)    {
                System.out.println(tagAs);
                System.out.println(i);
            }
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }
}

Note: adding .getAttributes().getNamedItem(“Name”).getNodeValue() to the print statement gives me null exception.
And the output is:

[xxxxxx-Set: null]
0
[xxxxxx-Set: null]
1
...
[xxxxxx-Set: null]
16

Answer 1

If you want to take all your Name attributes (it’s better to name them with lower case), use next approach:

Element xSet = (Element) doc.getElementsByTagName("xxxxxx-Set").item(0);
NodeList xSetTags = xSet.getElementsByTagName("tag3");

for(int i = 0; i < xSetTags.getLength(); i++)    {
    Element tag3 = (Element) xSetTags.item(i);
    System.out.println(tag3.getAttribute("Name"));
}

I made it using org.w3c.dom.Element class. It’s not the best idea to work with org.w3c.dom.Node, because this class represents not only xml elements, but attributes, comments and other too. Look documentation to get difference between Node and Element classes.