code: @Override
  	public void open(FileInputSplit split) throws IOException {
  		super.open(split);
  
  		DatumReader<E> datumReader;
  		if (org.apache.avro.specific.SpecificRecordBase.class.isAssignableFrom(avroValueType)) {
  			datumReader = new SpecificDatumReader<E>(avroValueType);
  		} else {
  			datumReader = new ReflectDatumReader<E>(avroValueType);
  		}
  		
  		LOG.info("Opening split " + split);
  		
  		SeekableInput in = new FSDataInputStreamWrapper(stream, (int) split.getLength());
  		
  		dataFileReader = DataFileReader.openReader(in, datumReader);
  		dataFileReader.sync(split.getStart());
  	}
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