### Question:
DRGElement extends NamedElement implements DynamicReadOnly,
                                                                 HasContentDefinitionId { @Override public String getContentDefinitionId() { return getId().getValue(); } DRGElement();  DRGElement(final Id id,
                      final Description description,
                      final Name name); @Override void setAllowOnlyVisualChange(final boolean allowOnlyVisualChange); @Override boolean isAllowOnlyVisualChange(); @Override ReadOnly getReadOnly(final String fieldName); @Override String getContentDefinitionId(); @Override String getDiagramId(); @Override void setDiagramId(final String dmnDiagramId); @Override void setContentDefinitionId(final String contentDefinitionId); DocumentationLinksHolder getLinksHolder(); void setLinksHolder(final DocumentationLinksHolder linksHolder);  }### Answer:
@Test public void testGetContentDefinitionId() { final String contentDefinitionId = "the id"; final Id id = mock(Id.class); when(drgElement.getId()).thenReturn(id); when(id.getValue()).thenReturn(contentDefinitionId); final String currentId = drgElement.getContentDefinitionId(); assertEquals(contentDefinitionId, currentId); }