Java: Function that parses XML data - nothing being outputted - java

I'm relatively new to XML processing with Java, so expect some mistakes, but anyway...I'm trying to parse the following XML data:
http://msdn.microsoft.com/en-us/library/ms762271(v=vs.85).aspx
I would like to accomplish this using a function, where the name of the XML tag and NodeList are passed in as parameters, and it returns the content.
Thanks.
import java.io.*;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.w3c.dom.Element;
import org.xml.sax.SAXException;
public class Files {
#SuppressWarnings("unused")
public static void main (String [] args) throws IOException, ParserConfigurationException, SAXException{
String address = "/home/leo/workspace/Test/Files/src/file.xml";
String author = "author";
String title = "title";
String genre = "genre";
String price = "price";
String publish = "publish_date";
String descr = "description";
File xmlFile = new File(address);
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = factory.newDocumentBuilder();
Document doc = dBuilder.parse(xmlFile);
doc.getDocumentElement().normalize();
System.out.println(doc.getDocumentElement().getNodeName());
NodeList n = doc.getElementsByTagName("book");
System.out.println("Number of books " + n.getLength());
getElement(author, n);
}
private static void getElement(String elementName, NodeList n){
for (int i = 0; i < n.getLength(); i++){
Node showNode = n.item(i);
Element showElement = (Element)showNode;
System.out.println(elementName + ": " +
showElement.getAttribute(elementName)
);
}
}
}

The problem is : showElement.getAttribute(elementName)
you want to get the value of a node,but getAttribute is to get the attribute of the node,you should figure out what attribute means in XML.
you can get the value like this:
private static void getElement(String elementName, NodeList n){
for (int i = 0; i < n.getLength(); i++){
Node showNode = n.item(i);
NodeList nl = showNode.getChildNodes();
for(int j=0;j<nl.getLength();j++)
{
Node nd=nl.item(j);
if(nd.getNodeName().equals(elementName))
{
System.out.println(elementName + ":" + nd.getTextContent());
}
}
}
}
}

Related

writing string to file in java

Below two classes. I have a problem with writing string to file in java. Why in my file xml.txt I get null? Why I can't write String a = px.readXml(url) ? In xml.txt I've only null
package xml;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.*;
import java.util.StringTokenizer;
import javax.xml.parsers.*;
import org.w3c.dom.*;
import org.xml.sax.SAXException;
public class PrintXml {
public String readXml(URL url) throws ParserConfigurationException, MalformedURLException, IOException, SAXException
{
//URL url = new URL("http://www.nbp.pl/kursy/xml/a093z150515.xml");
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse(url.openStream());
Element root = doc.getDocumentElement();
//System.out.println(root.getTagName());
NodeList children = root.getChildNodes();
int liczbaLinijek = children.getLength();
for(int i = 0; i<children.getLength();i++)
{
Node child = children.item(i);
if (child instanceof Element)
{
Element childElement = (Element)child;
NodeList childrenPozycja = childElement.getChildNodes();
for (int j = 0; j<childrenPozycja.getLength(); j++)
{
Node childPozycja = childrenPozycja.item(j);
if (childPozycja instanceof Element)
{
String nameChf = "CHF";
Double kurs;
Element childPozycjaElement = (Element) childPozycja;
String listaKursow = childPozycjaElement.getTextContent();
//System.out.println(listaKursow);
}
}
}
}
return null;
}
public String writeXml(String toFile) throws IOException
{
PrintWriter out = new PrintWriter(new FileWriter("xml.txt"));
out.println(toFile);
out.close();
return null;
}
}
and here is testing class:
package xml;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.*;
import java.util.StringTokenizer;
import javax.xml.parsers.*;
import org.w3c.dom.*;
import org.xml.sax.SAXException;
public class PrintXmlTester {
public static void main(String[] args) throws MalformedURLException,
ParserConfigurationException, SAXException, IOException {
URL url = new URL("http://www.nbp.pl/kursy/xml/a093z150515.xml");
PrintXml px = new PrintXml();
String a = px.readXml(url);
px.writeXml(a);
}
}
}
To return value of listaKursow you can add return statement in readXml() like below:
public String readXml(URL url) throws ParserConfigurationException, MalformedURLException, IOException, SAXException
{
//...
//Declare listaKursow here
String listaKursow = "";
for(int i = 0; i<children.getLength();i++)
{
//..
for (int j = 0; j<childrenPozycja.getLength(); j++)
{
Node childPozycja = childrenPozycja.item(j);
if (childPozycja instanceof Element)
{
String nameChf = "CHF";
Double kurs;
Element childPozycjaElement = (Element) childPozycja;
String listaKursowTemp = childPozycjaElement.getTextContent();
//System.out.println(listaKursow);
//return value of listaKursow
listaKursow = listaKursow + listaKursowTemp;
}
}
}
return listaKursow;
}
However you should note that this would return first value of listaKursow in Xml.
If you are looking for all values of elements as String, you can add them to a List and return list.toString() or concatenate String variable in each iteration.
EDIT: Based on your inputs I have modified my post to return all lists
#hitz answer is good, but I would suggest using StringBuilder for this. It is far more efficient and nicer to look at.
public String readXml(URL url) throws ParserConfigurationException, MalformedURLException, IOException, SAXException
{
//...
//Declare listaKursow here
final StringBuilder listaKursow = new StringBuilder();
for(int i = 0; i<children.getLength();i++)
{
//..
for (int j = 0; j<childrenPozycja.getLength(); j++)
{
final Node childPozycja = childrenPozycja.item(j);
if (childPozycja instanceof Element)
{
final String nameChf = "CHF";
Double kurs;
final Element childPozycjaElement = (Element) childPozycja;
listaKursow.append( childPozycjaElement.getTextContent() );
}
}
}
return listaKursow.toString();
}

java xml parsing dblp

this is the xml file
please how to parse the tag author example we dont know how many author for each inproceeding ?
<?xml version="1.0" encoding="ISO-8859-1"?>
<dblp>
<inproceedings mdate="2014-01-18" key="series/sci/AzzagL13">
<author>Hanane Azzag</author>
<author>Mustapha Lebbah</author>
<title>A New Way for Hierarchical and Topological Clustering.</title>
<pages>85-97</pages>
<year>2011</year>
<booktitle>EGC (best of volume)</booktitle>
<ee>http://dx.doi.org/10.1007/978-3-642-35855-5_5</ee>
<crossref>series/sci/2013-471</crossref>
<url>db/series/sci/sci471.html#AzzagL13</url>
</inproceedings>
<inproceedings mdate="2014-01-18" key="series/sci/RabatelBP13">
<author>Julien Rabatel</author>
<author>Sandra Bringay</author>
<author>Pascal Poncelet</author>
<title>Mining Sequential Patterns: A Context-Aware Approach.</title>
<pages>23-41</pages>
<year>2011</year>
<booktitle>EGC (best of volume)</booktitle>
<ee>http://dx.doi.org/10.1007/978-3-642-35855-5_2</ee>
<crossref>series/sci/2013-471</crossref>
<url>db/series/sci/sci471.html#RabatelBP13</url>
</inproceedings>
</dblp>
Use Xpath, it's fast and powerfull , these lines for your example return 5 lines
Code:
final Document document = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(new FileInputStream("input.xml"));
final XPath xPath = XPathFactory.newInstance().newXPath();
final NodeList nodeList = (NodeList) xPath.compile("//author").evaluate(document, XPathConstants.NODESET);
for (int i = 0; i < nodeList.getLength(); i++) {
System.out.println(nodeList.item(i).getFirstChild().getNodeValue());
}
Displays:
Hanane Azzag
Mustapha Lebbah
Julien Rabatel
Sandra Bringay
Pascal Poncelet
Following code parse using apache digester which is commonly used while parsing in real projects. Nice one from apache community
// Updated code as per you need.
import java.io.ByteArrayInputStream;
import java.io.FileInputStream;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map.Entry;
import org.apache.commons.digester.Digester;
import org.apache.commons.digester.Rule;
import org.apache.commons.digester.Rules;
import org.xml.sax.InputSource;
public class Parsing {
public static void main(String[] args) throws Exception{
InputStream data = new FileInputStream("E:\\workspace\\trunk\\Parsing\\src\\data.xml");
byte[] b = new byte[data.available()];
// data.read(b);
Digester digester = new Digester();
//Genearting Array list while encountering dblp xpath
digester.addObjectCreate("dblp", HashMap.class);
digester.addObjectCreate("dblp/inproceedings", ArrayList.class);
//Calling add method while encountering author xpath
AuthorRule rule = new AuthorRule();
digester.addRule("dblp/inproceedings/author", rule);
digester.addRule("dblp/inproceedings/title", rule);
digester.addRule("dblp/inproceedings", rule);
HashMap parsedData = (HashMap) digester.parse(data);
Iterator<Entry<String, ArrayList>> dataItr = parsedData.entrySet().iterator();
while(dataItr.hasNext()){
Entry<String, ArrayList> entry = dataItr.next();
System.out.println("Title : " + entry.getKey() + ", Authors" + entry.getValue().toString());
}
}
private static class AuthorRule extends Rule{
String currentTitle = "";
#Override
public void body(String namespace, String name, String text)
throws Exception {
HashMap object = (HashMap) digester.peek(1);
ArrayList authors = (ArrayList) digester.peek(0);
if(name.equals("title")){
currentTitle = text;
}
else if(name.equals("author")){
authors.add(text);
}
}
#Override
public void end(String namespace, String name) throws Exception {
HashMap object = (HashMap) digester.peek(1);
ArrayList authors = (ArrayList) digester.peek(0);
if(name.equals("inproceedings")){
object.put(currentTitle, authors);
}
}
}
}
output::
Title : A New Way for Hierarchical and Topological Clustering., Authros[Hanane Azzag, Mustapha Lebbah]
Title : Mining Sequential Patterns: A Context-Aware Approach., Authros[Julien Rabatel, Sandra Bringay, Pascal Poncelet]
there are number of ways, e.g. via DOM:
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import java.io.File;
public class XmlAuthorReader {
public static void main(String argv[]) {
try {
File fXmlFile = new File(<filePath>);
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(fXmlFile);
NodeList nList = doc.getElementsByTagName("author");
System.out.println(nList.getLength()+ " author(s) found");
for (int temp = 0; temp < nList.getLength(); temp++) {
Node nNode = nList.item(temp);
System.out.println("Author: " + nNode.getTextContent());
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
you can find more variants here: http://www.mkyong.com/tutorials/java-xml-tutorials/

blank string in XML parsing in android

I am trying to make an XML parser. However, the following code just gives blank output.
The "heyya" message in the getElementValue() function is getting printed which tells that empty string is returned. Please help.
import java.io.IOException;
import java.io.StringReader;
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.InputSource;
import org.xml.sax.SAXException;
public class XMLParser {
public Document getDomElement(String xml)
{
Document doc=null;
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
try{
DocumentBuilder db = dbf.newDocumentBuilder();
InputSource is = new InputSource();
is.setCharacterStream(new StringReader(xml));
doc = db.parse(is);
}catch (ParserConfigurationException e){
System.out.println(e.getMessage());
return null;
} catch(SAXException e){
System.out.println(e.getMessage());
return null;
} catch(IOException e){
System.out.println(e.getMessage());
return null;
}
return doc;
}
public String getValue(Element item, String str)
{
NodeList n = item.getElementsByTagName(str);
return this.getElementValue(n.item(0));
}
public final String getElementValue(Node elem)
{
Node child;
if(elem!=null){
if(elem.hasChildNodes()){
for(child=elem.getFirstChild(); child!=null; child = child.getNextSibling()){
if(child.getNodeType() == Node.TEXT_NODE){
return child.getNodeValue();
}
}
}
}
//System.out.println("heyya");
return "";
}
}
class createData
{
static final String KEY_ID = "id"; //parent node
static final String KEY_NAME = "name";
static final String KEY_COST = "cost";
static final String KEY_DESC = "description";
public void createArrayList()
{
//ArrayList<HashMap<String, String>> userData = new ArrayList<HashMap<String, String>>();
XMLParser parser = new XMLParser();
//obtain xml as string here
String xml="<menu>\n\t<item>\n\t\t<id>1</id>\n\t\t<name>Margherita</name>\n\t\t<cost>155</cost>\n\t\t<description>Single cheese topping</description>\n\t</item></menu>\n";
Document doc = parser.getDomElement(xml);
NodeList node_L = doc.getElementsByTagName(KEY_ID);
for(int i=0; i<node_L.getLength(); i++)
{
//HashMap<String, String> map = new HashMap<String, String>();
Element e = (Element)node_L.item(i);
String name = parser.getValue(e, KEY_NAME);
String cost = parser.getValue(e, KEY_COST);
String description = parser.getValue(e, KEY_DESC);
System.out.println(name+" "+cost+" "+description);
//map.put(KEY_NAME, name);
//map.put(KEY_COST, cost);
//map.put(KEY_DESC, description);
//userData.add(map);
}
System.out.println("hello pop!");
//System.out.println(userData.get(0));
}
public static void main(String args[])throws IOException
{
createData ob =new createData();
ob.createArrayList();
}
}
This is the problem.
NodeList node_L = doc.getElementsByTagName(KEY_ID);
You are getting id here, but the id is just a subtag in your item. Replace that with this:-
NodeList node_L = doc.getElementsByTagName("item");
Note:- Your parent node is ITEM and not ID.
You can get your ID as you get your other tags.
String id = parser.getValue(e, KEY_ID);

Parsing XML using java DOM

Im new in Java, and i have a task to Parse one xml file using http with current url http://belbooner.site40.net/testXmls/details.xml
I created Some class to parse it using Dom method, but im having java.lang.NullPointerException while trying to get one Nodes value
So here's the code
import java.security.KeyStore.Builder;
import java.util.*;
import java.io.*;
import java.net.*;
import javax.swing.text.Document;
import javax.xml.*;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;
import org.w3c.dom.*;
import org.w3c.dom.CharacterData;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
public class RequestResponse {
public static void main(String[] args) throws ParserConfigurationException, IOException, SAXException {
URL url = new URL("http://belbooner.site40.net/testXmls/details.xml");
RequestResponse req= new RequestResponse();
req.getHTTPXml(url);
}
void getHTTPXml(URL url) throws ParserConfigurationException, IOException, SAXException {
//URL url = new URL("http://belbooner.site40.net/testXmls/details.xml");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("ACCEPT","application/xml");
InputStream xml = conn.getInputStream();
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
org.w3c.dom.Document document = builder.parse(xml);
System.out.println(document);
String doctype = conn.getContentType();
System.out.print(doctype);
NodeList root = document.getChildNodes();
Node server = getNodes("server",root);
Node check = getNodes("check", server.getChildNodes());
NodeList nodes = check.getChildNodes();
String checkid= getNodeValue("checkid", nodes);
System.out.println(checkid);
conn.disconnect();
//return (Document) DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(xml);
}
Node getNodes(String tagName, NodeList nodes) {
for(int i=0; i< nodes.getLength();i++) {
Node node= nodes.item(i);
if(node.getNodeName().equalsIgnoreCase(tagName)) {
return node;
}
}
return null;
}
String getNodeValue(String tagName, NodeList nodes ) {
for ( int i = 0; i < nodes.getLength(); i++ ) {
Node node = nodes.item(i);
if (node.getNodeName().equalsIgnoreCase(tagName)) {
NodeList childNodes = node.getChildNodes();
for (int y = 0; y < childNodes.getLength(); y++ ) {
Node data = childNodes.item(y);
if ( data.getNodeType() == Node.TEXT_NODE ) {
return data.getNodeValue();
}
if(data instanceof CharacterData) {
CharacterData cd= (CharacterData) data;
return cd.getData();
}
}
}
}
return "";
}
}
The stacktrace I'm getting is the following:
application/xmlException in thread "main" java.lang.NullPointerException at
RequestResponse.getHTTPXml(RequestResponse.java:45) at
RequestResponse.main(RequestResponse.java:22)
After changin Node server = getNodes("server",root); to `
Node resultNode = getNodes("result", root);
Node server = getNodes("server", resultNode.getChildNodes());`
`application/xmlException in thread "main" java.lang.NullPointerException
at RequestResponse.getHTTPXml(RequestResponse.java:49)
at RequestResponse.main(RequestResponse.java:22)
`
Please help me to find the issue.
The problem is that Node server = getNodes("server",root); is returning null.
Why does this happen? Well look how you implemented getNodes
Node getNodes(String tagName, NodeList nodes) {
for(int i=0; i< nodes.getLength();i++) {
Node node= nodes.item(i);
if(node.getNodeName().equalsIgnoreCase(tagName)) {
return node;
}
}
return null;
}
You are giving as input the document root which is a single "Result" node, you iterate through it and you compare if the node's name is in this case "server" which never will be, hence you return null and get a NPE.
Your node look up must be done in the following way:
NodeList root = document.getChildNodes();
// Keep in mind that you have the following structure:
// result
// server
// checks
// check
// checkId
// check
// checkId
Node resultNode = getNodes("result", root);
Node server = getNodes("server", resultNode.getChildNodes());
Node checks = getNodes("checks", server.getChildNodes());
NodeList childNodes = checks.getChildNodes();
for (int i = 0; i < childNodes.getLength(); i++) {
Node possibleCheck = childNodes.item(i);
if (possibleCheck.getNodeName().equals("check")) {
String checkid = getNodeValue("checkid", possibleCheck.getChildNodes());
System.out.println(checkid);
}
}
This way you'll be iterating through the correct node list.
Using XPath is more efficient and flexible (than normal iteration) while parsing xml.
XPath Tutorial from IBM
XPath Reference Orielly tutorial
Xpath Reference Oracle java tutorial
Try below code.
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathExpressionException;
import javax.xml.xpath.XPathFactory;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
public class RequestResponse {
public static void main(String[] args) throws ParserConfigurationException,
IOException, SAXException {
URL url = new URL("http://belbooner.site40.net/testXmls/details.xml");
RequestResponse req = new RequestResponse();
req.getHTTPXml(url);
}
void getHTTPXml(URL url) throws ParserConfigurationException, IOException,
SAXException {
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("ACCEPT", "application/xml");
InputStream xml = conn.getInputStream();
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
org.w3c.dom.Document document = builder.parse(xml);
System.out.println(document);
String doctype = conn.getContentType();
System.out.println(doctype);
XPathFactory pathFactory = XPathFactory.newInstance();
XPath path = pathFactory.newXPath();
XPathExpression expression;
try {
expression = path.compile("/result/server/checks/check/checkid");
NodeList nodeList = (NodeList) expression.evaluate(document,
XPathConstants.NODESET);
String checkids[] = getNodeValue(nodeList);
for (String checkid : checkids) {
System.out.print(checkid + ", ");
}
} catch (XPathExpressionException e) {
e.printStackTrace();
}
conn.disconnect();
}
String[] getNodeValue(NodeList nodes) {
String checkIds[] = new String[nodes.getLength()];
for (int i = 0; i < nodes.getLength(); i++) {
Node node = nodes.item(i);
checkIds[i] = node.getTextContent();
}
return checkIds;
}
}

Why is this java code not parsing my Xml correctly?

I've written class to parse some xml into an object and it's not working correctly, when I try and get the value of a node I get a null rather than the contents of the node.
Here is a simplified version of my class that just does the xml parsing of a single node:
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.apache.log4j.Logger;
import org.apache.log4j.xml.DOMConfigurator;
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 XmlReaderCutDown {
private static Logger logger = Logger.getLogger(CtiButtonsXmlReader.class);
public static void testXml(String confFile){
DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory.newInstance();
try {
DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder();
Document doc = docBuilder.parse(new File(confFile));
doc.getDocumentElement().normalize();
if (logger.isDebugEnabled()){
logger.debug("The root element is " + doc.getDocumentElement().getNodeName());
}
NodeList rows = doc.getElementsByTagName("row");
NodeList topRowButtons = ((Element)rows.item(0)).getElementsByTagName("button");
logger.debug("Top row has " +topRowButtons.getLength() + " items.");
Node buttonNode = topRowButtons.item(0);
NodeList nodeList = ((Element)buttonNode).getElementsByTagName("id");
logger.debug("Node list count for "+ "id" + " = " + nodeList.getLength());
Element element = (Element)nodeList.item(0);
String xx = element.getNodeValue();
logger.debug(xx);
String elementValue = ((Node)element).getNodeValue();
if (elementValue != null) {
elementValue = elementValue.trim();
}
else {
logger.debug("Value was null");
}
logger.debug("Node id = "+ elementValue);
} catch (ParserConfigurationException e) {
logger.fatal(e.toString(),e);
} catch (SAXException e) {
logger.fatal(e.toString(),e);
} catch (IOException e) {
logger.fatal(e.toString(),e);
} catch (Exception e) {
logger.fatal(e.toString(),e);
}
}
public static void main(String[] args){
DOMConfigurator.configure("log4j.xml");
testXml("test.xml");
}
}
And here is a stripped down version of my xml file:
<?xml version="1.0"?>
<root>
<row>
<button>
<id>this is an id</id>
<action>action</action>
<image-src>../images/img.png</image-src>
<alt-text>alt txt</alt-text>
<tool-tip>Tool tip</tool-tip>
</button>
</row>
</root>
This is what the logging statments output:
DEBUG XmlReaderCutDown - The root element is root
DEBUG XmlReaderCutDown - Top row has 1 items.
DEBUG XmlReaderCutDown - Node list count for id = 1
DEBUG XmlReaderCutDown -
DEBUG XmlReaderCutDown - Value was null
DEBUG XmlReaderCutDown - Node id = null
Why isn't it getting the text in the xml node?
I'm running using JDK 1.6_10
Because the element you get is the parent element of the text one, containing the text you need. To access the text of this element, you shall use getTextContent instead of getNodeValue.
For more information, see the table in the Node javadoc.
See http://java.sun.com/j2se/1.5.0/docs/api/org/w3c/dom/Node.html . Element.getNodeValue() always returns null. You should use Element.getTextContent()
Consider using XPath as an alternative to manually walking nodes:
public static void testXml(String confFile)
throws XPathExpressionException {
XPathFactory xpFactory = XPathFactory.newInstance();
XPath xpath = xpFactory.newXPath();
NodeList rows = (NodeList) xpath.evaluate("root/row",
new InputSource(confFile), XPathConstants.NODESET);
for (int i = 0; i < rows.getLength(); i++) {
Node row = rows.item(i);
String id = xpath.evaluate("button/id", row);
System.out.println("id=" + id);
}
}
public static void main(String[] args)
throws XPathExpressionException {
testXml("test.xml");
}

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