I found the following easy solution to extracting values from XML file.
import java.io.IOException; import org.w3c.dom.*; import org.xml.sax.SAXException; import javax.xml.parsers.*; import javax.xml.xpath.*; public class XPathExample { public static void main(String[] args) throws ParserConfigurationException, SAXException, IOException, XPathExpressionException { DocumentBuilderFactory domFactory = DocumentBuilderFactory.newInstance(); domFactory.setNamespaceAware(true); // never forget this! DocumentBuilder builder = domFactory.newDocumentBuilder(); Document doc = builder.parse("c:/temp/books.xml"); XPathFactory factory = XPathFactory.newInstance(); XPath xpath = factory.newXPath(); XPathExpression expr = xpath.compile("//book[author='Neal Stephenson']/title/text()"); Object result = expr.evaluate(doc, XPathConstants.NODESET); NodeList nodes = (NodeList) result; for (int i = 0; i < nodes.getLength(); i++) { System.out.println(nodes.item(i).getNodeValue()); } } }
This uses xpath to extract all books title where the author is Neal Stephenson from the following xml
<inventory> <book year="2000"> <title>Snow Crash</title> <author>Neal Stephenson</author> <publisher>Spectra</publisher> <isbn>0553380958</isbn> <price>14.95</price> </book> <book year="2005"> <title>Burning Tower</title> <author>Larry Niven</author> <author>Jerry Pournelle</author> <publisher>Pocket</publisher> <isbn>0743416910</isbn> <price>5.99</price> </book> <book year="1995"> <title>Zodiac</title> <author>Neal Stephenson</author> <publisher>Spectra</publisher> <isbn>0553573862</isbn> <price>7.50</price> </book> <!-- more books... --> </inventory>
Now this works fine on JDK5 but i am using jdk 1.4 Can this be converted to the java 1.4 equivalent?
All i am trying to do is extract a value from an xml element. For example, in the above xml, i just want something that is the equivalent of getElementByTag("title").
Thanks