Java XPath – How to Get Attribute Value

/path to/node/@attribute_name

/path to/node[filter-expression]/@attribute_name

<?xml version="1.0" encoding="utf-8" ?>
<inventory>
  <!--Test is test comment-->
  <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>
</inventory>

DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
factory.setNamespaceAware(true); // never forget this!
DocumentBuilder builder = factory.newDocumentBuilder();
Document doc = builder.parse("inventory.xml");

XPathFactory xpathfactory = XPathFactory.newInstance();
XPath xpath = xpathfactory.newXPath();

XPathExpression expr = xpath.compile("//book/@year");
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());
}

2000
2005
1995

XPathExpression expr = xpath.compile("//book[author='Neal Stephenson']/@year");
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());
}

2000
1995