[ 
https://issues.apache.org/jira/browse/MRUNIT-165?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13510918#comment-13510918
 ] 

Hudson commented on MRUNIT-165:
-------------------------------

Integrated in mrunit-trunk #506 (See 
[https://builds.apache.org/job/mrunit-trunk/506/])
    MRUNIT-165: MapReduceDriver calls Mapper#cleanup for each input instead of 
once (unit test contributed by Yoni Ben-Meshulam) (Revision 
92ad229dafea47db18fa978e809d13261721a806)

     Result = SUCCESS
dbeech : 
https://git-wip-us.apache.org/repos/asf?p=mrunit.git&a=commit&h=92ad229dafea47db18fa978e809d13261721a806
Files : 
* src/test/java/org/apache/hadoop/mrunit/mapreduce/StatefulMapper.java
* src/test/java/org/apache/hadoop/mrunit/mapreduce/TestStatefulMapReduce.java

                
> MapReduceDriver calls Mapper#cleanup for each input instead of once
> -------------------------------------------------------------------
>
>                 Key: MRUNIT-165
>                 URL: https://issues.apache.org/jira/browse/MRUNIT-165
>             Project: MRUnit
>          Issue Type: Bug
>    Affects Versions: 0.9.0
>            Reporter: Yoni Ben-Meshulam
>            Assignee: Dave Beech
>             Fix For: 1.0.0
>
>         Attachments: reproduce_MRUNIT-165.patch
>
>
> MapReduceDriver calls the Mapper#run method for each input, causing the 
> Mapper#cleanup method to be called multiple times. 
> I believe this is a bug, since the contract in MapReduce is that, for a 
> single Mapper instance, the Mapper#cleanup method is only called once after 
> all inputs to that mapper have been processed. I might be mistaken in my 
> assumption here.
> This would not be an issue, were it not for the fact that MapReduceDriver has 
> only a single instance of Mapper.
> One solution might be to pass the Mapper _class_ into the MapReduceDriver and 
> create a new instance for each input. Another solution might be to call the 
> MapDriver with multiple inputs (which AFAIK is not possible).
> See attached patch for an example of a stateful mapper and a test which fails 
> due to the bug.

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Reply via email to