@Test
 public void testIsApplicableToProducerTrue() throws Exception {
   when(userReferenceUpdateXpathExtractor.getNewUserRefDescr(any(Node.class)))
       .thenReturn(XPathString.valueOf(USER_REF_DESCR));
   Boolean isApplicable = userReferenceDescriptionUpdateProducer.isApplicable(userRefDescrDoc);
   assertTrue(isApplicable);
 }
 @Test
 public void testIsApplicableToProducerFalse() throws Exception {
   when(userReferenceUpdateXpathExtractor.getNewUserRefDescr(any(Node.class))).thenReturn(null);
   Boolean isApplicable = userReferenceDescriptionUpdateProducer.isApplicable(invoiceRefDoc);
   assertFalse(isApplicable);
 }