@Test
 public void testNestedTypes() {
   MessageType schema = MessageTypeParser.parseMessageType(Paper.schema.toString());
   Type type = schema.getType("Links", "Backward");
   assertEquals(PrimitiveTypeName.INT64, type.asPrimitiveType().getPrimitiveTypeName());
   assertEquals(0, schema.getMaxRepetitionLevel("DocId"));
   assertEquals(1, schema.getMaxRepetitionLevel("Name"));
   assertEquals(2, schema.getMaxRepetitionLevel("Name", "Language"));
   assertEquals(0, schema.getMaxDefinitionLevel("DocId"));
   assertEquals(1, schema.getMaxDefinitionLevel("Links"));
   assertEquals(2, schema.getMaxDefinitionLevel("Links", "Backward"));
 }