presto-hive/src/main/java/io/prestosql/plugin/hive/util/HiveUtil.java/HiveUtil/getInputFormatClass
class HiveUtil:    @SuppressWarnings({"unchecked", "RedundantCast"})
    private static Class<? extends InputFormat<?, ?>> getInputFormatClass(JobConf conf, String inputFormatName)
            throws ClassNotFoundException
    {
        // CDH uses different names for Parquet
        if ("parquet.hive.DeprecatedParquetInputFormat".equals(inputFormatName) ||
                "parquet.hive.MapredParquetInputFormat".equals(inputFormatName)) {
            return MapredParquetInputFormat.class;
        }

        Class<?> clazz = conf.getClassByName(inputFormatName);
        return (Class<? extends InputFormat<?, ?>>) clazz.asSubclass(InputFormat.class);
    }