assertNotNull( "Selection expected", structuredSelection );
Object firstElement = structuredSelection.getFirstElement();
assertNotNull( "First element should not be null", firstElement );
Id idFilter = (Id) firstElement;
assertFalse( "Expect a non empty selection", idFilter.getIdentifiers().isEmpty() );
assertFalse( "Expect a non empty selection", idFilter.getIDs().isEmpty() );
Set<Object> ds = (idFilter).getIDs();
String[] fids = ds.toArray(new String[0]);
assertEquals("Expect selected ID to match", feature2.getID(), fids[0]);