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Parse xml dom to an object

How can I fill an array with such object?
class Sam{
String id;
String type;
String data;
}
from xml structure:
<Table name="Sam">
<Row id="374058">
<Col name="ID.1">374058</Col>
<Col name="TYPE.1">mob</Col>
</Row>
<Row id="374059">
<Col name="ID.1">374059</Col>
<Col name="TYPE.1">ff</Col>
</Row>
</Table>
Found such "Table" but what i shoud do next to collect data from "Row"?
List<Sam> samList = new new ArrayList<>();
NodeList nameNodeList = xml.getDocumentElement().getElementsByTagName("Table");
if (nameNodeList != null) {
for (int i = 0; i < nameNodeList.getLength(); i++) {
Node node = nameNodeList.item(i);
if (node.getAttributes().getNamedItem("name").getNodeValue().equals("Sam") &&
node.getNodeType() == Node.ELEMENT_NODE) {
Element element = (Element) node;
//what should i do next, how can i fined ID,TYPE,DATA?
}
}
}

Try this one. I try to code the problem and get the following output. This code parses your XML and constructs the Sam object.
Code:
import java.util.ArrayList;
import java.util.List;
import org.w3c.dom.NodeList;
import org.w3c.dom.*;
import javax.xml.parsers.*;
import java.io.*;
public class XmlParse {
public static void main(String[] args) {
XmlParse xmlParse = new XmlParse();
xmlParse.xmlToObj();
}
public void xmlToObj() {
try {
File inputFile = new File("sam.xml");
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.parse(inputFile);
doc.getDocumentElement().normalize();
System.out.println("Root element: " + doc.getDocumentElement().getNodeName());
NodeList nodeList = doc.getElementsByTagName("Row");
Node node = null;
List<Sam> samList = new ArrayList<>();
if(nodeList != null && nodeList.getLength() > 0) {
for(int i=0; i < nodeList.getLength(); i++) {
node = nodeList.item(i);
NodeList innerNodeList = doc.getElementsByTagName("Col");
Node innerNodeID = innerNodeList.item(0);
Node innerNodeType = innerNodeList.item(1);
String id = innerNodeID.getTextContent();
String type = innerNodeType.getTextContent();
Sam sam = new Sam(id, type, null);
System.out.println(sam.toString());
samList.add(sam);
}
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
}
class Sam {
String id;
String type;
String data;
public Sam(String id, String type, String data) {
this.id = id;
this.type = type;
this.data = data;
}
#Override
public String toString() {
return "Sam [id=" + id + ", type=" + type + ", data=" + data + "]";
}
}
Output:
Root element: Table
Sam [id=374058, type=mob, data=null]
Sam [id=374058, type=mob, data=null]
input : sam.xml
<Table name="Sam">
<Row id="374058">
<Col name="ID">374058</Col>
<Col name="TYPE">mob</Col>
</Row>
<Row id="374059">
<Col name="ID">374059</Col>
<Col name="TYPE">ff</Col>
</Row>
</Table>

you can use JAXB Unmarshalling
You can also see some examples in Examples JAXB Unmarshalling

How to read an online XML file for currency rates in java

I'm building a simple currency converter which needs to sue online rates. I found the following API from the European Central Bank to use:
http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml
My problem is im struggling to implement it. Here is what i have so far after using a bunch of different sources to try and get this code together.
try{
URL url = new URL("http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml");
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document doc = db.parse(new InputSource(url.openStream()));
doc.getDocumentElement().normalize();
NodeList nodeList1 = doc.getElementsByTagName("Cube");
for(int i = 0; i < nodeList1.getLength(); i++){
Node node = nodeList1.item(i);
}
}
catch(Exception e){
}
So what i thought is that this code would take down all the nodes which tart with "Cube", and contain the rates.
Anyone have an easier wya to pull down the rates from the API into an array in the order they appear on the XML as that's all I'm trying to do
Thanks

XPath is one way to answer this, since you just want to extract information from the XML and not change the XML. The structure of the XML suggests that you're looking for nodes that are Cube nodes, that are child of Cube which is also a child of Cube -- Cube nested three times, so extract nodes with an XPath compiled using this String: "//Cube/Cube/Cube". This looks for nodes that have Cube nested 3 times located anywhere (the //) in the Document:
XPathExpression expr = xpath.compile("//Cube/Cube/Cube");
Then check the nodes for a "currency" attribute. If they have this, then they also have a "rate" attribute, and then extract this information.
NamedNodeMap attribs = node.getAttributes();
if (attribs.getLength() > 0) {
Node currencyAttrib = attribs.getNamedItem(CURRENCY);
if (currencyAttrib != null) {
String currencyTxt = currencyAttrib.getNodeValue();
String rateTxt = attribs.getNamedItem(RATE).getNodeValue();
// ...
}
}
Where CURRENCY = "currency" and RATE = "rate"
For example:
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import javax.xml.parsers.*;
import javax.xml.xpath.*;
import org.w3c.dom.Document;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
public class TestXPath {
private static final String CURRENCY = "currency";
private static final String CUBE_NODE = "//Cube/Cube/Cube";
private static final String RATE = "rate";
public static void main(String[] args) {
List<CurrencyRate> currRateList = new ArrayList<>();
DocumentBuilderFactory builderFactory =
DocumentBuilderFactory.newInstance();
DocumentBuilder builder = null;
try {
builder = builderFactory.newDocumentBuilder();
} catch (ParserConfigurationException e) {
e.printStackTrace();
}
Document document = null;
String spec = "http://www.ecb.europa.eu/stats/eurofxref/eurofxref-daily.xml";
try {
URL url = new URL(spec);
InputStream is = url.openStream();
document = builder.parse(is);
XPathFactory xPathfactory = XPathFactory.newInstance();
XPath xpath = xPathfactory.newXPath();
String xPathString = CUBE_NODE;
XPathExpression expr = xpath.compile(xPathString);
NodeList nl = (NodeList) expr.evaluate(document, XPathConstants.NODESET);
for (int i = 0; i < nl.getLength(); i++) {
Node node = nl.item(i);
NamedNodeMap attribs = node.getAttributes();
if (attribs.getLength() > 0) {
Node currencyAttrib = attribs.getNamedItem(CURRENCY);
if (currencyAttrib != null) {
String currencyTxt = currencyAttrib.getNodeValue();
String rateTxt = attribs.getNamedItem(RATE).getNodeValue();
currRateList.add(new CurrencyRate(currencyTxt, rateTxt));
}
}
}
} catch (SAXException | IOException | XPathExpressionException e) {
e.printStackTrace();
}
for (CurrencyRate currencyRate : currRateList) {
System.out.println(currencyRate);
}
}
}
public class CurrencyRate {
private String currency;
private String rate; // ?double
public CurrencyRate(String currency, String rate) {
super();
this.currency = currency;
this.rate = rate;
}
public String getCurrency() {
return currency;
}
public String getRate() {
return rate;
}
#Override
public String toString() {
return "CurrencyRate [currency=" + currency + ", rate=" + rate + "]";
}
// equals, hashCode,....
}

Generate an xml file using DOM

I have a local SQL table has these records in it:
ID currentRank previousRank PlayerName Money
1 1 1 Max 15
2 2 2 Rick 20
3 3 3 Alice 13
4 4 4 Beth 25
I want to convert it to make it look like this:
<player ID="1">
<currentRank>1</currentRank>
<previousRank>1</previousRank>
<PlayerName>Max</PlayerName>
<Money>15</Money>
</player>
<player ID="2">
<currentRank>2</currentRank>
<previousRank>2</previousRank>
<PlayerName>Rick</PlayerName>
<Money>20</Money>
</player>
<player ID="3">
<currentRank>3</currentRank>
<previousRank>3</previousRank>
<PlayerName>Alice</PlayerName>
<Money>13</Money>
</player>
<player ID="4">
<currentRank>4</currentRank>
<previousRank>4</previousRank>
<PlayerName>Alice</PlayerName>
<Money>13</Money>
</player>
I have a class called Tplayers that gets and sets all the fields that looks like:
public class Tplayers implements Serializable
{
private int ID;
private String currentRank
private String previousRank
private String PlayerName
private String Money
}
public Tplayers () {
ID = 0;
currentRank = "";
previousRank = "";
PlayerName = "";
Money = "";
}
public Tplayers (int playerId, String currentRank, String previousRank, String PlayerName, String Money) {
this.playerId = playerId;
this.currentRank = currentRank;
this.previousRank = previousRank;
this.PlayerName = PlayerName;
his.Money = Money;
}
public int getID() {
return ID;
}
public void setID(int ID) {
this.ID = ID;
}
public String getCurrentRank() {
return currentRank;
}
public void setCurrentRank(String currentRank) {
this.currentRank = currentRank;
}
public String getPreviousRank() {
return previousRank;
}
public void setPreviousRank(String previousRank) {
this.previousRank = previousRank;
}
public String getPlayerName() {
return PlayerName;
}
public void setPlayerName(String PlayerName) {
this.PlayerName = PlayerName;
}
public String getMoney() {
return Money;
}
public void setMoney(String Money) {
this.Money = Money;
}
Finally I have DbMethods Class which contains a players Arraylist where I have stored all of the data from the tables in 'player' objects:
public static ArrayList<Tplayers > getAllPlayers() {
ArrayList<Tplayers > players = new ArrayList();
Connection conn = null;
PreparedStatement ps = null;
ResultSet rs = null;
try {
conn = DBConnectionFactory.getConnection();
String sql = "SELECT * FROM players";
ps = conn.prepareStatement(sql);
rs = ps.executeQuery();
while (rs.next()) {
Tplayers player = new Tplayers();
player.setID(rs.getInt("ID"));
player.setCurrentRank(rs.getString("CurrentRank"));
player.setPreviousRank(rs.getString("PreviousRank"));
player.setPlayerName(rs.getString("PlayerName"));
player.setMoney(rs.getString("Money"));
players.add(player);
}
return players;
} catch (SQLException e) {
System.err.println("Message: " + e.getMessage());
System.err.println("SQL State: " + e.getSQLState());
System.err.println("Error Code: " + e.getErrorCode());
return null;
} finally {
DBConnectionFactory.close(rs);
DBConnectionFactory.close(ps);
DBConnectionFactory.close(conn);
}
}
Now I want to create a database class with a main method that upon execution will create an XML file that resembles the one described but I'm not sure how to start, I know how to create an XML document but only by hard coding it.
Any assistance is greatly appreciated and if any clarification is needed do not hesitate to ask.
Also all imports are there I just didn't include them in the post to prevent clutter
After posting this I will be searching other sites for more information so the above code may change and I will note any changes at the top.

I would use JAXB, here is the basic idea
#XmlRootElement(name="players")
public class Test1 {
#XmlElement(name="player")
List<Tplayers> list = new ArrayList<>();
public static void main(String[] args) throws Exception {
Test1 t1 = new Test1();
... add players to list
JAXB.marshal(t1, System.out);
}
}
output
<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<players>
<player>
<currentRank></currentRank>
<ID>0</ID>
<money></money>
<playerName></playerName>
<previousRank></previousRank>
</player>
<player>
<currentRank></currentRank>
<ID>0</ID>
<money></money>
<playerName></playerName>
<previousRank></previousRank>
</player>
</players>
find a simple tutorial on JAXB here http://www.vogella.com/articles/JAXB/article.html

Seen as you basically have every thing you need to get started, I'm only going to focus on the basics of generating a XML document and populating it with data...
This example will output the result to String which I display, but you can supplement it with any OutputStream you need
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
public class XMLTest {
public static void main(String[] args) {
try {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder builder = factory.newDocumentBuilder();
// Create a new document
Document xmlDoc = builder.newDocument();
// Create root node for the document...
Element root = xmlDoc.createElement("Players");
xmlDoc.appendChild(root);
//----> Add a for-loop here <---
// Then with each player reference, fill out the deatils
// similar to below....
// Create a "player" node
Element player = xmlDoc.createElement("player");
// Set the players ID attribute
player.setAttribute("ID", "1");
// Create currentRank node...
Element currentRank = xmlDoc.createElement("currentRank");
currentRank.setTextContent("1");
player.appendChild(currentRank);
// Create previousRank node...
Element previousRank = xmlDoc.createElement("previousRank");
previousRank.setTextContent("1");
player.appendChild(previousRank);
// Create playerName node...
Element playerName = xmlDoc.createElement("PlayerName");
playerName.setTextContent("Max");
player.appendChild(playerName);
// Create Money node...
Element money = xmlDoc.createElement("Money");
money.setTextContent("15");
player.appendChild(money);
// Add the player to the root node...
root.appendChild(player);
// ---> End for-loop <--- //
ByteArrayOutputStream baos = null;
try {
baos = new ByteArrayOutputStream();
Transformer tf = TransformerFactory.newInstance().newTransformer();
tf.setOutputProperty(OutputKeys.INDENT, "yes");
tf.setOutputProperty(OutputKeys.METHOD, "xml");
tf.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
DOMSource domSource = new DOMSource(xmlDoc);
StreamResult sr = new StreamResult(baos);
tf.transform(domSource, sr);
baos.flush();
System.out.println(new String(baos.toByteArray()));
} finally {
try {
baos.close();
} catch (Exception e) {
}
}
} catch (IOException | TransformerException exp) {
exp.printStackTrace();
} catch (ParserConfigurationException exp) {
exp.printStackTrace();
}
}
}
Which outputs...
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<Players>
<player ID="1">
<currentRank>1</currentRank>
<previousRank>1</previousRank>
<PlayerName>Max</PlayerName>
<Money>15</Money>
</player>
</Players>
Now, this is all taken from library code I've hobbled together of the past few years, so I'm not even sure of a single website which would cover all this...

How can i find APIs for a weather forcast websites?

I making a java application that give the user notification with the weather conditions.
i used the yahoo weather API provided by yahoo like that link :
http://weather.yahooapis.com/forecastrss?w=2502265
and all i have to do is to change the eight numbered code that is in the URL in order to change the city.
that's working perfect, but there are two problems facing me now:
the first one, i want to implement a lot of weather forecast sources in my application not just the yahoo weather and i can't find a similar service in any other weather forecast websites.
the second one, i want to obtain the codes of all the cities in yahoo weather as for sure i won't ask the user to enter his city code, but to enter his city name and i'll match it with the code.
and here is the code that works with me in java:
the code to return the XML file:
package search;
import java.io.IOException;
import java.io.InputStream;
import java.io.StringWriter;
import java.net.URL;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
public class Process {
public static void main(String[] args) throws IOException {
Display disp = new Display();
Document doc = generateXML("1940345");
disp.getConditions(doc);
}
public static Document generateXML(String code) throws IOException {
String url = null;
String XmlData = null;
// creating the URL
url = "http://weather.yahooapis.com/forecastrss?w=" + code;
URL xmlUrl = new URL(url);
InputStream in = xmlUrl.openStream();
// parsing the XmlUrl
Document doc = parse(in);
return doc;
}
public static Document parse(InputStream is) {
Document doc = null;
DocumentBuilderFactory domFactory;
DocumentBuilder builder;
try {
domFactory = DocumentBuilderFactory.newInstance();
domFactory.setValidating(false);
domFactory.setNamespaceAware(false);
builder = domFactory.newDocumentBuilder();
doc = builder.parse(is);
} catch (Exception ex) {
System.err.println("unable to load XML: " + ex);
}
return doc;
}
}
the code to display the temperature and humidity in that city :
package search;
import java.io.File;
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 Display {
static void getConditions(Document doc) {
String city = null;
String unit = null;
try {
doc.getDocumentElement().normalize();
NodeList nList = doc.getElementsByTagName("rss");
for (int temp = 0; temp < nList.getLength(); temp++) {
Node nNode = nList.item(temp);
if (nNode.getNodeType() == Node.ELEMENT_NODE) {
Element eElement = (Element) nNode;
NodeList nl = eElement
.getElementsByTagName("yweather:location");
for (int tempr = 0; tempr < nl.getLength(); tempr++) {
Node n = nl.item(tempr);
if (nNode.getNodeType() == Node.ELEMENT_NODE) {
Element e = (Element) n;
city = e.getAttribute("city");
System.out.println("The City Is : " + city);
}
}
NodeList nl2 = eElement
.getElementsByTagName("yweather:units");
for (int tempr = 0; tempr < nl2.getLength(); tempr++) {
Node n2 = nl2.item(tempr);
if (nNode.getNodeType() == Node.ELEMENT_NODE) {
Element e2 = (Element) n2;
unit = e2.getAttribute("temperature");
}
}
NodeList nl3 = eElement
.getElementsByTagName("yweather:condition");
for (int tempr = 0; tempr < nl3.getLength(); tempr++) {
Node n3 = nl3.item(tempr);
if (nNode.getNodeType() == Node.ELEMENT_NODE) {
Element e3 = (Element) n3;
System.out.println("The Temperature In " + city
+ " Is : " + e3.getAttribute("temp") + " "
+ unit);
}
}
NodeList nl4 = eElement
.getElementsByTagName("yweather:atmosphere");
for (int tempr = 0; tempr < nl4.getLength(); tempr++) {
Node n4 = nl4.item(tempr);
if (nNode.getNodeType() == Node.ELEMENT_NODE) {
Element e4 = (Element) n4;
System.out.println("The Humidity In " + city
+ " Is : " + e4.getAttribute("humidity"));
}
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
}

You can use Metwit weather api simply passing latitude and longitude.
If you can implement them client-side: 200 request/day (ip based throttling) no authentication required. Worldwide coverage, JSON and REST compliant. You can register for extra API calls for free and if you still need it to call them server side the basic plan is pretty cheap.
Full disclosure: I own this API.

Take a look on this discussion. It seems relevant:
https://stackoverflow.com/questions/4876800/is-there-an-international-weather-forecast-api-that-is-not-limited-for-non-comme
Additionally type "weather forecast api" in google. There are tons of references to APIs that support several weather services.

Here's a list of Weather APIs that are available via the Temboo Java SDK:
https://temboo.com/library/keyword/weather/

You can use YQL (yahoo query language) to find the WOEID by city name like
var lclqry = escape('select * from geo.places where text="OKLAHOMA CITY"')
var lclurl = "http://query.yahooapis.com/v1/public/yql?q=" + lclqry + "&format=json&callback=?";

I know this is an old question, but i found it and as Sai suggested i have written code in java that send YQL query and retrieve WOEID number. Than it uses it to get weather from yahoo-weather-java-api. It needs gson dependecy which you can get by adding dependency to maven. I hope this will help someone.
EDIT
If there is more than one WOEID number for given town name, than getWeather returns weather for town with first WOEID returned.
CODE
Weather.java:
import com.github.fedy2.weather.YahooWeatherService;
import com.github.fedy2.weather.data.Channel;
import com.github.fedy2.weather.data.unit.DegreeUnit;
import com.google.gson.*;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLEncoder;
import javax.xml.bind.JAXBException;
/**
*
* #author robert
*/
public class Weather
{
public Channel getWeather(String townName) throws CantFindWeatherException
{
try
{
String baseUrl = "http://query.yahooapis.com/v1/public/yql?q=";
String query =
"select woeid from geo.places where text=\"" +
townName + "\"";
String fullUrlStr = baseUrl + URLEncoder.encode(query, "UTF-8") +
"&format=json";
URL fullUrl = new URL(fullUrlStr);
ResultObject resultObject = null;
ResultArray resultArray = null;
try (InputStream is = fullUrl.openStream();
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr))
{
String result = "";
String read;
while ((read = br.readLine()) != null)
{
result += read;
}
Gson gson = new Gson();
try
{
resultObject = gson.fromJson(result, ResultObject.class);
}
catch (com.google.gson.JsonSyntaxException ex)
{
resultArray = gson.fromJson(result, ResultArray.class);
}
}
Integer woeid = null;
if (resultObject != null)
{
if (resultObject.query.results != null)
{
woeid = resultObject.query.results.place.woeid;
}
}
else if (resultArray != null)
{
woeid = resultArray.query.results.place[0].woeid;
}
if (woeid != null)
{
YahooWeatherService service = new YahooWeatherService();
Channel channel = service.getForecast(woeid.toString(),
DegreeUnit.CELSIUS);
return channel;
}
else
{
throw new CantFindWeatherException();
}
}
catch (IOException | JsonSyntaxException | JAXBException ex)
{
throw new CantFindWeatherException(ex);
}
}
private static class ResultObject
{
public QueryObject query;
}
private static class ResultArray
{
public QueryArray query;
}
private static class QueryObject
{
public int count;
public String created;
public String lang;
public ResultsObject results;
}
private static class QueryArray
{
public int count;
public String created;
public String lang;
public ResultsArray results;
}
private static class ResultsObject
{
public Place place;
}
private static class ResultsArray
{
public Place[] place;
}
private static class Place
{
public int woeid;
}
}
CantFindWeatherException.java:
/**
*
* #author robert
*/
public class CantFindWeatherException extends Exception
{
public CantFindWeatherException()
{
}
public CantFindWeatherException(String message)
{
super(message);
}
public CantFindWeatherException(String message, Throwable cause)
{
super(message, cause);
}
public CantFindWeatherException(Throwable cause)
{
super(cause);
}
}

As for the first question, I've build a website using forecast.io. It's pretty good. Good API and 1000 free calls/day. It uses latitute/longitude to find the weather of a place.
As for the second question, I would resolve what the user puts in with the Google Geocoding Api. So when they search for "New York", you check if you already have the relevant coordinates in your database, otherwise, you do an API call to Google Geocoding.

java find value of an xml attribute

this is my xml :
<-tobject.subject tobject.subject.refnum="01016000" />
<-tobject.subject tobject.subject.refnum="10004000" />
I want to extract 01016000 and 10004000 from it .
I used this code:
NodeList nodeLst4 = doc.getElementsByTagName("tobject.subject");
if (nodeLst4 != null) {
int numberofCOdes = nodeLst4.getLength();
aSubjectCodes = new String[numberofCOdes];
for (int i = 0; i < numberofCOdes; i++) {
XPath xpath = XPathFactory.newInstance().newXPath();
aSubjectCodes[i] = xpath.evaluate("//tobject.subject/#tobject.subject.refnum", doc);
the problem is that when i loop through it the evaluate method just return first number and do not give me the second value.
and i am not sure if using xpath.evaluate is good idea or not.
Thanks

there is no need to use the doc.getElementsByTagName.
You are mixing plain DOM with XPath.
Your xpath is correct:
package net.davymeers;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.Collection;
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.Document;
import org.w3c.dom.NodeList;
import org.xml.sax.SAXException;
public class XpathTest {
private static String XMLSTRING = "<data>"
+ "<tobject.subject tobject.subject.refnum=\"01016000\" />\r\n"
+ "\r\n"
+ "<tobject.subject tobject.subject.refnum=\"10004000\" />"
+ "</data>";
/**
* #param args
*/
public static void main(final String[] args) {
final Document doc = createDocument();
final XPath xpath = createXpath();
final NodeList nodes = findElements(
"//tobject.subject/#tobject.subject.refnum", doc, xpath);
final Collection<String> results = convertToCollection(nodes);
for (final String result : results) {
System.out.println(result);
}
}
private static Document createDocument() {
Document doc = null;
try {
final DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory
.newInstance();
documentBuilderFactory.setNamespaceAware(true); // never forget
// this!
final DocumentBuilder builder = documentBuilderFactory
.newDocumentBuilder();
doc = builder.parse(new ByteArrayInputStream(XMLSTRING
.getBytes("ISO-8859-1")));
} catch (final UnsupportedEncodingException exception) {
// TODO handle exception
} catch (final SAXException exception) {
// TODO handle exception
} catch (final IOException exception) {
// TODO handle exception
} catch (final ParserConfigurationException exception) {
// TODO handle exception
}
return doc;
}
private static XPath createXpath() {
final XPathFactory xpathFactory = XPathFactory.newInstance();
final XPath xpath = xpathFactory.newXPath();
return xpath;
}
private static NodeList findElements(final String xpathExpression,
final Document doc, final XPath xpath) {
NodeList nodes = null;
if (doc != null) {
try {
final XPathExpression expr = xpath.compile(xpathExpression);
final Object result = expr
.evaluate(doc, XPathConstants.NODESET);
nodes = (NodeList) result;
} catch (final XPathExpressionException exception) {
// TODO handle exception
}
}
return nodes;
}
private static Collection<String> convertToCollection(final NodeList nodes) {
final Collection<String> result = new ArrayList<String>();
if (nodes != null) {
for (int i = 0; i < nodes.getLength(); i++) {
result.add(nodes.item(i).getNodeValue());
}
}
return result;
}
}

Here's a useful class I found a while back for XMLFiles. Takes a lot of the work off of your shoulders.
import java.io.FileInputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
/**
* XMLFile.java
*
* XML file object that represents an xml file and its properties. Used to
* simplify the process of reading from and writing to XML files.
*
* Derived from unknown source. Implemented on 12/03/09. Permission given to
* implement and modify code.
*/
public class XMLFile {
private String name;
private String content;
private Map<String, String> nameAttributes = new HashMap<String, String>();
private Map<String, List<XMLFile>> nameChildren = new HashMap<String, List<XMLFile>>();
private static Element rootElement(String filename, String rootName) {
FileInputStream fileInputStream = null;
try {
fileInputStream = new FileInputStream(filename);
DocumentBuilderFactory builderFactory = DocumentBuilderFactory
.newInstance();
DocumentBuilder builder = builderFactory.newDocumentBuilder();
Document document = builder.parse(fileInputStream);
Element rootElement = document.getDocumentElement();
if (!rootElement.getNodeName().equals(rootName))
throw new RuntimeException("Could not find root node: "
+ rootName);
return rootElement;
} catch (Exception exception) {
throw new RuntimeException(exception);
} finally {
if (fileInputStream != null) {
try {
fileInputStream.close();
} catch (Exception exception) {
throw new RuntimeException(exception);
}
}
}
}
/**
* #param (String) Filepath of XML File (String) Root of XML File
**/
public XMLFile(String filename, String rootName) {
this(rootElement(filename, rootName));
}
/**
* #param (Element) XML File Element
**/
private XMLFile(Element element) {
this.name = element.getNodeName();
this.content = element.getTextContent();
NamedNodeMap namedNodeMap = element.getAttributes();
int n = namedNodeMap.getLength();
for (int i = 0; i < n; i++) {
Node node = namedNodeMap.item(i);
String name = node.getNodeName();
addAttribute(name, node.getNodeValue());
}
NodeList nodes = element.getChildNodes();
n = nodes.getLength();
for (int i = 0; i < n; i++) {
Node node = nodes.item(i);
int type = node.getNodeType();
if (type == Node.ELEMENT_NODE)
addChild(node.getNodeName(), new XMLFile((Element) node));
}
}
/**
* Adds attribute to ???
*
* #param (String) Attribute Name (String) Attribute Value
**/
private void addAttribute(String name, String value) {
nameAttributes.put(name, value);
}
/**
* Adds child directory to ???
*
* #param (String) Name of New Child Directory (XMLFile) XML Documentation
* of Child
**/
private void addChild(String name, XMLFile child) {
List<XMLFile> children = nameChildren.get(name);
if (children == null) {
children = new ArrayList<XMLFile>();
nameChildren.put(name, children);
}
children.add(child);
}
public String name() {
return name;
}
public String content() {
return content;
}
/**
*
**/
public XMLFile child(String name) {
List<XMLFile> children = children(name);
if (children.size() != 1)
throw new RuntimeException("Could not find individual child node: "
+ name);
return children.get(0);
}
/**
*
**/
public List<XMLFile> children(String name) {
List<XMLFile> children = nameChildren.get(name);
return children == null ? new ArrayList<XMLFile>() : children;
}
/**
* Gets the value of a specific field and converts it to a String object
*
* #param (String) Name of Field
**/
public String string(String name) {
String value = nameAttributes.get(name);
if (value == null)
throw new RuntimeException("Could not find attribute: " + name
+ ", in node: " + this.name);
return value;
}
/**
* Gets the value of a specific field and converts it to an int
*
* #param (String) Name of Field
**/
public int integer(String name) {
return Integer.parseInt(string(name));
}
/**
* Gets the value of a specific field and converts it to an
* ArrayList<String>
*
* #param (String) Name of Field
**/
public ArrayList<String> arrayListString(String name) {
String left = new String();
int finished = 0;
ArrayList<String> list = new ArrayList<String>();
try {
left = nameAttributes.get(name);
} catch (Exception e) {
System.err.println("Exception: " + e.getMessage());
}
while (finished == 0) {
if (left.indexOf(", ") > -1) {
list.add(left.substring(0, left.indexOf(", ")));
left = left.substring(left.indexOf(", ") + 2);
} else {
list.add(left);
finished = 1;
}
}
return list;
}
}

Would this work for you? I am parsing RSS XML from here:
http://www.kraftfoods.com/rss/dinnerRecipes.aspx
Look at Media and URL towards the bottom:
package recipeSearchAndFinder.xml;
import java.util.ArrayList;
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.NamedNodeMap;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
public class DomFeedParser extends BaseFeedParser {
public DomFeedParser(String feedUrl) {
super(feedUrl);
}
public List<Message> parse() {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
List<Message> messages = new ArrayList<Message>();
try {
DocumentBuilder builder = factory.newDocumentBuilder();
Document dom = builder.parse(this.getInputStream());
Element root = dom.getDocumentElement();
NodeList items = root.getElementsByTagName(ITEM);
for (int i = 0; i < items.getLength(); i++) {
Message message = new Message();
Node item = items.item(i);
NodeList properties = item.getChildNodes();
for (int j = 0; j < properties.getLength(); j++) {
Node property = properties.item(j);
String name = property.getNodeName();
if (name.equalsIgnoreCase(TITLE)) {
message.setTitle(property.getFirstChild()
.getNodeValue());
} else if (name.equalsIgnoreCase(LINK)) {
message.setLink(property.getFirstChild().getNodeValue());
} else if (name.equalsIgnoreCase(DESCRIPTION)) {
StringBuilder text = new StringBuilder();
NodeList chars = property.getChildNodes();
for (int k = 0; k < chars.getLength(); k++) {
text.append(chars.item(k).getNodeValue());
}
message.setDescription(text.toString());
} else if (name.equalsIgnoreCase(PUB_DATE)) {
message.setDate(property.getFirstChild().getNodeValue());
} else if (name.equalsIgnoreCase(MEDIA)) {
NamedNodeMap nMap = property.getAttributes();
String mediaurl = nMap.getNamedItem("url")
.getNodeValue();
message.setMedia(mediaurl);
}
}
messages.add(message);
}
} catch (Exception e) {
throw new RuntimeException(e);
}
return messages;
}
}