presto-record-decoder/src/main/java/io/prestosql/decoder/avro/AvroColumnDecoder.java/ObjectValueProvider/getBoolean
class ObjectValueProvider:        @Override
        public boolean getBoolean()
        {
            if (value instanceof Boolean) {
                return (Boolean) value;
            }
            throw new PrestoException(DECODER_CONVERSION_NOT_SUPPORTED, format("cannot decode object of '%s' as '%s' for column '%s'", value.getClass(), columnType, columnName));
        }