-implements_declaration = 'implements' interface_list;
-extends_declaration = 'extends' interface_list;
-interface_list
- = {tail:} interface_list ',' full_class_name
- | {head:} full_class_name;
-
-throws_declaration = 'throws' exception_list?;
-exception_list
- = {tail:} exception_list ',' type
- | {head:} type;
+implements_declaration = 'implements' types;
+extends_declaration = 'extends' types;
+throws_declaration = 'throws' types?;