XPath

• DOM Level 3 includes an optional XPath module in the org.w3c.dom.xpath package.

• The feature string "XPath" with the version "3.0" tests for the presence of this module. For example,

  if (!impl.hasFeature("XPath", "3.0")) {
    System.err.println("This DOM implementation does not support XPath");  
    return;
  }

• An XPathEvaluator object processes an XPath expression and returns an XPathResult.

• In DOM implementations that support XPath, the same classes that implement org.w3c.dom.Document implement XPathEvaluator. No special constructor or factory class is required. Just cast the Document object you want to query to XPathEvaluator.