DataFileStream<GenericRecord> reader = new DataFileStream<GenericRecord>(
input, new GenericDatumReader<GenericRecord>());
Schema schema = reader.getSchema();
DataFileWriter<GenericRecord> writer = new DataFileWriter<GenericRecord>(
new GenericDatumWriter<GenericRecord>());
CodecFactory codec = opts.valueOf(codecOpt).equals("deflate")
? CodecFactory.deflateCodec(Integer.parseInt(levelOpt.value(opts)))
: CodecFactory.fromString(codecOpt.value(opts));
writer.setCodec(codec);
for (String key : reader.getMetaKeys()) {
if (!DataFileWriter.isReservedMeta(key)) {