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https://issues.apache.org/jira/browse/HADOOP-4065?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12629305#action_12629305
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Pete Wyckoff commented on HADOOP-4065:
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Nice. Will the TFileRecordReader fit into this paradigm? How were you going to
implement the TFileRecordReader?
TFile is very similar to TRecordStream - but more full featured - sorted and
seek by key. But, TRecordStream is meant to be readable/writable in many
languages (first cut c++, java, python and perl). It's primary use case is
non-hadoop - just a robust way of logging data, but secondarily, there's no
reason not to enable directly reading/writing to one from Hadoop as it's a
waste to open one, read it and write it out as a TFile or SF if one doesn't
need the richer functionality that sequence file and tfile support.
-- pete
> support for reading binary data from flat files
> -----------------------------------------------
>
> Key: HADOOP-4065
> URL: https://issues.apache.org/jira/browse/HADOOP-4065
> Project: Hadoop Core
> Issue Type: Bug
> Components: mapred
> Reporter: Joydeep Sen Sarma
>
> like textinputformat - looking for a concrete implementation to read binary
> records from a flat file (that may be compressed).
> it's assumed that hadoop can't split such a file. so the inputformat can set
> splittable to false.
> tricky aspects are:
> - how to know what class the file contains (has to be in a configuration
> somewhere).
> - how to determine EOF (would be nice if hadoop can determine EOF and not
> have the deserializer throw an exception (which is hard to distinguish from
> a exception due to corruptions?)). this is easy for non-compressed streams -
> for compressed streams - DecompressorStream has a useful looking
> getAvailable() call - except the class is marked package private.
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