@Test
 public void addContainerPropertyMetadata() {
   Container container = new IndexedContainer();
   PropertyMetadata metadata =
       new PropertyMetadata("propertyName", String.class, null, "propertyName");
   ContainerUtils.addContainerProperty(container, metadata);
   assertTrue(
       "container should contains a property 'propertyName'",
       container.getContainerPropertyIds().contains(metadata.getPropertyName()));
   assertEquals(String.class, container.getType("propertyName"));
 }