XPATH使用namespace

XPath xpath = XPathFactory.newInstance().newXPath();
		NamespaceContext nsContext = new XHTMLNamespaceContext();
		xpath.setNamespaceContext(nsContext);
XPathExpression expr = xpath.compile("//xhtml:TABLE");

public class XHTMLNamespaceContext implements NamespaceContext {

	@Override
	public String getNamespaceURI(String prefix) {
		return "http://www.w3.org/1999/xhtml";
	}

	@Override
	public String getPrefix(String namespaceURI) {
		throw new UnsupportedOperationException();
	}

	@Override
	public Iterator getPrefixes(String namespaceURI) {
		throw new UnsupportedOperationException();
	}

}