@Test
 public void testGetChildren() {
   System.out.println("testGetChildren");
   for (Category root : serviceStub.getRootCategories()) {
     Collection<?> childrenIds = container.getChildren(root.getId());
     List<Category> children = serviceStub.getChildren(root);
     assertEquals(children.size(), childrenIds.size());
     Iterator<?> idIterator = childrenIds.iterator();
     Iterator<Category> childIterator = children.iterator();
     while (idIterator.hasNext() && childIterator.hasNext()) {
       assertEquals(idIterator.next(), childIterator.next().getId());
     }
   }
 }
 @Test
 public void testGetChildren_Nonexistent() {
   System.out.println("testGetChildren_Nonexistent");
   assertNull(container.getChildren(-123l));
 }