JDOM 2 and xpath

Question

Here is the following code excerpted from the Spring-ws manual:

public class HolidayEndpoint {

  private static final String NAMESPACE_URI = "http://mycompany.com/hr/schemas";

  private XPath startDateExpression;

  private XPath endDateExpression;

  private XPath nameExpression;

  private HumanResourceService humanResourceService;

  @Autowired
  public HolidayEndpoint(HumanResourceService humanResourceService)                      (2)
      throws JDOMException {
    this.humanResourceService = humanResourceService;

    Namespace namespace = Namespace.getNamespace("hr", NAMESPACE_URI);

    startDateExpression = XPath.newInstance("//hr:StartDate");
    startDateExpression.addNamespace(namespace);

    endDateExpression = XPath.newInstance("//hr:EndDate");
    endDateExpression.addNamespace(namespace);

    nameExpression = XPath.newInstance("concat(//hr:FirstName,' ',//hr:LastName)");
    nameExpression.addNamespace(namespace);
  }

My problem is that this appears to be using JDOM 1.0 and I'd like to use JDOM 2.0.

How do I convert this code from JDOM 1.0 to JDOM 2.0? Why hasn't spring updated their sample code?

Thanks!

Fatal

Have you updated your imports to use jDom2? For example, the import for Element is import org.jdom2.Element;. – Conic

Answer 1

JDOM2 is still relatively new.... but, the XPath factory in JDOM 1.x is particularly broken... and JDOM 2.x has a new api for it. The old API exists for backward compatibility/migration. Have a look at this document here for some reasoning, and the new API in JDOM 2.x.

In your case, you probably want to replace the code with something like:

XPathExpression<Element> startDateExpression = 
    XPathFactory.instance().compile("//hr:StartDate", Filters.element(), null, namespace);

List<Element> startdates = startDateExpression.evaluate(mydocument);

Rolf

Xylene

once I've done that, how do I use the xPathExpression to retrieve the value? the valueOf method is gone. – Fatal

The XPathExpression has the evaluate and EvaluateFirst which respectively return a list of all nodes matching the expression, or just the first matching node. in the example above, startdates is a list containing all the StartDate Elements in the document. – Xylene

Thanks again for all of your help. Now I'm lost, though. I'm working through static.springsource.org/spring-ws/sites/2.0/reference/html/… on chapter 3. I'm trying to figure out how to convert the code there to use JDOM 2. – Fatal

Answer 2

In order to parse the value using the code above from Rolf, iterate through the list or get the first element from the List assuming there's only one.

List<Element> startdates = startDateExpression.evaluate(mydocument);

    for (Element e: startdates){
        logger.debug("value= " + e.getValue());
    }

or

List<Element> startdates = startDateExpression.evaluate(mydocument);
logger.debug("value " + startdates.get(0).getValue();

Oswaldooswalt