How to get the attribute value of an xml node using java

Question

I have an xml which looks like this:

{ <xml><ep><source type="xml">...</source><source type="text">..</source></ep></xml>}

Here I want to retrieve the value of "source type" where type is an attribute.

I tried the following, which didn't work:

DocumentBuilderFactory domFactory = DocumentBuilderFactory.newInstance();
try {
    DocumentBuilder builder = domFactory.newDocumentBuilder();
    Document dDoc = builder.parse("D:/workspace1/ereader/src/main/webapp/configurations/config.xml");
    System.out.println(dDoc);
    XPath xPath = XPathFactory.newInstance().newXPath();
    Node node = (Node) xPath.evaluate("//xml/source/@type/text()", dDoc, XPathConstants.NODE);
    System.out.println(node);
} catch (Exception e) {
    e.printStackTrace();

This also didn't work:

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
InputSource is = new InputSource(new StringReader("config.xml"));
Document doc = builder.parse(is);

NodeList nodeList = doc.getElementsByTagName("source");

for (int i = 0; i < nodeList.getLength(); i++) {
    Node node = nodeList.item(i);

    if (node.hasAttributes()) {
        Attr attr = (Attr) node.getAttributes().getNamedItem("type");
        if (attr != null) {
            String attribute = attr.getValue();
            System.out.println("attribute: " + attribute);
        }
    }
}

Have u tried using VTD-XML vtd-xml.sourceforge.net It is faster and more memory efficient. — Rosdi Kasim
– Rosdi Kasim, Commented Aug 9, 2012 at 4:38
hi Rosdi, No i've n't tried, anyways ATR's code works fine, and my snippet too:) thanks for ur kind response — Sruthi
– Sruthi, Commented Aug 9, 2012 at 5:04

nhahtdh · Accepted Answer · 2012-08-10 05:42:12Z

34

Since your question is more generic so try to implement it with XML Parsers available in Java .If you need it in specific to parsers, update your code here what you have tried yet

<?xml version="1.0" encoding="UTF-8"?>
<ep>
    <source type="xml">TEST</source>
    <source type="text"></source>
</ep>

DocumentBuilderFactory domFactory = DocumentBuilderFactory.newInstance();
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse("uri to xmlfile");
XPathFactory xPathfactory = XPathFactory.newInstance();
XPath xpath = xPathfactory.newXPath();
XPathExpression expr = xpath.compile("//ep/source[@type]");
NodeList nl = (NodeList) expr.evaluate(doc, XPathConstants.NODESET);

for (int i = 0; i < nl.getLength(); i++)
{
    Node currentItem = nl.item(i);
    String key = currentItem.getAttributes().getNamedItem("type").getNodeValue();
    System.out.println(key);
}

edited Aug 10, 2012 at 5:42

nhahtdh

56.9k15 gold badges131 silver badges164 bronze badges

answered Aug 8, 2012 at 11:15

thar45

3,5705 gold badges35 silver badges49 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

Sruthi Over a year ago

i've tried the above snippet and i dono to proceed with, kindly help me!! i need to get the value "xml" and "text" alone. that's my requirement.

Sruthi Over a year ago

ATR, Its actually //xml/ep/source/@type i've edited few statements in ur code.. and it works fine.. thanks :)

Srikanth Josyula Over a year ago

Is there a way i can get the value in between the tags, in above sample, <source type="xml">TEST</source>, how can i read TEST

mabroukb · Accepted Answer · 2012-08-08 14:53:12Z

4

try something like this :

    DocumentBuilder builder = DocumentBuilderFactory.newInstance().newDocumentBuilder();
    Document dDoc = builder.parse("d://utf8test.xml");

    XPath xPath = XPathFactory.newInstance().newXPath();
    NodeList nodes = (NodeList) xPath.evaluate("//xml/ep/source/@type", dDoc, XPathConstants.NODESET);
    for (int i = 0; i < nodes.getLength(); i++) {
        Node node = nodes.item(i);
        System.out.println(node.getTextContent());
    }

please note the changes :

we ask for a nodeset (XPathConstants.NODESET) and not only for a single node.
the xpath is now //xml/ep/source/@type and not //xml/source/@type/text()

PS: can you add the tag java to your question ? thanks.

answered Aug 8, 2012 at 14:53

mabroukb

7014 silver badges11 bronze badges

1 Comment

Sruthi Over a year ago

mabroukb, thanks:) added java tag:) ur explanations made me clear.. Thanks alot!!

nhahtdh · Accepted Answer · 2012-08-10 05:43:48Z

2

I'm happy that this snippet works fine:

DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document document = db.parse(new File("config.xml"));
NodeList nodeList = document.getElementsByTagName("source");
for(int x=0,size= nodeList.getLength(); x<size; x++) {
    System.out.println(nodeList.item(x).getAttributes().getNamedItem("type").getNodeValue());
}

edited Aug 10, 2012 at 5:43

nhahtdh

56.9k15 gold badges131 silver badges164 bronze badges

answered Aug 9, 2012 at 5:00

Sruthi

4793 gold badges6 silver badges14 bronze badges

Comments

Dan Pickard · Accepted Answer · 2014-12-22 13:49:39Z

1

use

document.getElementsByTagName(" * ");

to get all XML elements from within an XML file, this does however return repeating attributes

example:

NodeList list = doc.getElementsByTagName("*");

System.out.println("XML Elements: ");

        for (int i=0; i<list.getLength(); i++) {

            Element element = (Element)list.item(i);
            System.out.println(element.getNodeName());
        }

answered Dec 22, 2014 at 13:49

Dan Pickard

4836 silver badges15 bronze badges

Comments

vtd-xml-author · Accepted Answer · 2016-04-26 00:25:40Z

1

Below is the code to do it in VTD-XML

import com.ximpleware.*;

public class queryAttr{
     public static void main(String[] s) throws VTDException{
         VTDGen vg= new VTDGen();
         if (!vg.parseFile("input.xml", false))
            return false;
         VTDNav vn = vg.getNav();
         AutoPilot ap = new AutoPilot(vn);
         ap.selectXPath("//xml/ep/source/@type");
         int i=0;
         while((i = ap.evalXPath())!=-1){
               system.out.println(" attr val ===>"+ vn.toString(i+1));

         }
     }
}

answered Apr 26, 2016 at 0:25

vtd-xml-author

3,3874 gold badges24 silver badges30 bronze badges

Comments

Tamil veera Cholan · Accepted Answer · 2016-02-09 13:41:54Z

public static void main(String[] args) throws IOException {
    String filePath = "/Users/myXml/VH181.xml";
    File xmlFile = new File(filePath);
    DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
    DocumentBuilder dBuilder;
    try {
        dBuilder = dbFactory.newDocumentBuilder();
        Document doc = dBuilder.parse(xmlFile);
        doc.getDocumentElement().normalize();
        printElement(doc);
        System.out.println("XML file updated successfully");
    } catch (SAXException | ParserConfigurationException e1) {
        e1.printStackTrace();
    }
}
private static void printElement(Document someNode) {
    NodeList nodeList = someNode.getElementsByTagName("choiceInteraction");
    for(int z=0,size= nodeList.getLength();z<size; z++) {
            String Value = nodeList.item(z).getAttributes().getNamedItem("id").getNodeValue();
            System.out.println("Choice Interaction Id:"+Value);
        }
    }

we Can try this code using method

Sanjay Bharwani · Accepted Answer · 2021-09-10 09:04:18Z

Below is the utility method I have written to get value of any node from the root Document object and a given XPATH.

public String getValue(Document doc, String xPath) throws Exception {
   XPathFactory factory = XPathFactory.newInstance();
   XPath path = factory.newXPath();
   XPathExpression expression = path.compile(xPath);
   Node node = (Node) expression.evaluate(doc,XPathConstants.NODE);
   return node.getFirstChild().getNodeValue();
}

All the libraries are from java.xml.xpath and org.w3c.dom.

Now all you need the root document element and correct Path. For your example if will /ep/source/@type

So, basically XPAth is to navigate till the element you are after and followed by /@attributeName you are interested in.

Please node /ep/source@type won't work. (I wasted 30 min troubleshooting this).

Collectives™ on Stack Overflow

How to get the attribute value of an xml node using java

7 Answers 7

3 Comments

1 Comment

Comments

Comments

Comments

Comments

Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

7 Answers 7

3 Comments

1 Comment

Comments

Comments

Comments

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related