code: @Override
      public Object getRequestContents() {
          MediaUriType mediaUriType = new MediaUriType();
          mediaUriType.setUri(getProxyData().getServiceUri().toString()
                  + this.secondaryEntityUri.toString());
          JAXBElement<MediaUriType> mediaUriTypeElement = new JAXBElement<MediaUriType>(
                  new QName(Constants.ODATA_DATA_NS, "uri"), MediaUriType.class,
                  mediaUriType);
          Document document = documentBuilder.newDocument();
          document.setXmlStandalone(true);
          try {
              marshaller.marshal(mediaUriTypeElement, document);
          } catch (JAXBException e) {
              throw new RuntimeException(e);
          }
          return document;
      }
docs: /*
  (non-Javadoc)
  
  @see com.microsoft.windowsazure.services.media.entityoperations.
  DefaultActionOperation#getRequestContents()