You are viewing a plain text version of this content. The canonical link for it is here.
Posted to common-dev@hadoop.apache.org by "zhuweimin (JIRA)" <ji...@apache.org> on 2009/03/05 06:23:56 UTC
[jira] Commented: (HADOOP-1722) Make streaming to handle non-utf8
byte array
[ https://issues.apache.org/jira/browse/HADOOP-1722?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12679078#action_12679078 ]
zhuweimin commented on HADOOP-1722:
-----------------------------------
Klaas Bosteels,hi
my case is read binary data and generate text data by mappers.
can you teach me the usage.the following is correct?
$ hadoop jar contrib/streaming/hadoop-0.19.1-streaming.jar
-input data
-output result
-mapper "wc -c"
-numReduceTasks 0
-io rawbytes
the result is null.
> Make streaming to handle non-utf8 byte array
> --------------------------------------------
>
> Key: HADOOP-1722
> URL: https://issues.apache.org/jira/browse/HADOOP-1722
> Project: Hadoop Core
> Issue Type: Improvement
> Components: contrib/streaming
> Reporter: Runping Qi
> Assignee: Klaas Bosteels
> Fix For: 0.21.0
>
> Attachments: HADOOP-1722-branch-0.18.patch, HADOOP-1722-branch-0.19.patch, HADOOP-1722-v2.patch, HADOOP-1722-v3.patch, HADOOP-1722-v4.patch, HADOOP-1722-v4.patch, HADOOP-1722-v5.patch, HADOOP-1722-v6.patch, HADOOP-1722.patch
>
>
> Right now, the streaming framework expects the output sof the steam process (mapper or reducer) are line
> oriented UTF-8 text. This limit makes it impossible to use those programs whose outputs may be non-UTF-8
> (international encoding, or maybe even binary data). Streaming can overcome this limit by introducing a simple
> encoding protocol. For example, it can allow the mapper/reducer to hexencode its keys/values,
> the framework decodes them in the Java side.
> This way, as long as the mapper/reducer executables follow this encoding protocol,
> they can output arabitary bytearray and the streaming framework can handle them.
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.