SequenceFileWriterDemo.py

#!/usr/bin/env python
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# to you under the Apache License, Version 2.0 (the
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#
#     http://www.apache.org/licenses/LICENSE-2.0
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from hadoop.io.SequenceFile import CompressionType
from hadoop.io import LongWritable
from hadoop.io import SequenceFile

def writeData(writer):
    key = LongWritable()
    value = LongWritable()

    for i in range(1000):
        key.set(1000 - i)
        value.set(i)
        print('[%d] %s %s' % (writer.getLength(), key.toString(), value.toString()))
        writer.append(key, value)

if __name__ == '__main__':
    writer = SequenceFile.createWriter('test.seq', LongWritable, LongWritable)
    writeData(writer)
    writer.close()

    writer = SequenceFile.createWriter('test-record.seq', LongWritable, LongWritable, compression_type=CompressionType.RECORD)
    writeData(writer)
    writer.close()

    writer = SequenceFile.createWriter('test-block.seq', LongWritable, LongWritable, compression_type=CompressionType.BLOCK)
    writeData(writer)
    writer.close()