protected boolean processResources()
    {
      List<Product> validProducts = new ArrayList<Product>();
      List<Product> invalidProducts = new ArrayList<Product>();
      List<URI> invalidURIs = new ArrayList<URI>();
      ResourceSet resourceSet = editingDomain.getResourceSet();
      for (URI uri : getURIs())
      {
        BaseResource resource = BaseUtil.loadResourceSafely(resourceSet, uri);
        Product product = (Product)EcoreUtil.getObjectByType(resource.getContents(), SetupPackage.Literals.PRODUCT);
        if (product == null)
        {
          invalidURIs.add(uri);
        }
        else if (product.eContainer() != null)
        {
          invalidProducts.add(product);
        }
        else
        {
          validProducts.add(product);
        }
      }

<setup:Product
    xmi:version="2.0"
    xmlns:xmi="http://www.omg.org/XMI"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:setup="http://www.eclipse.org/oomph/setup/1.0"
    xmlns:setup.p2="http://www.eclipse.org/oomph/setup/p2/1.0"
    name="my.product"
    label="My Product">