[
https://issues.apache.org/jira/browse/HADOOP-9124?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Tom White resolved HADOOP-9124.
-------------------------------
Resolution: Fixed
Fix Version/s: 1.2.0
Committed to branch 1.
> SortedMapWritable violates contract of Map interface for equals() and
> hashCode()
> --------------------------------------------------------------------------------
>
> Key: HADOOP-9124
> URL: https://issues.apache.org/jira/browse/HADOOP-9124
> Project: Hadoop Common
> Issue Type: Bug
> Components: io
> Affects Versions: 1.1.1, 2.0.2-alpha
> Reporter: Patrick Hunt
> Assignee: Surenkumar Nihalani
> Priority: Minor
> Fix For: 1.2.0, 2.0.3-alpha, 0.23.7
>
> Attachments: hadoop-9124-branch1.patch, HADOOP-9124.patch,
> HADOOP-9124.patch, HADOOP-9124.patch, HADOOP-9124.patch, HADOOP-9124.patch,
> HADOOP-9124.patch, HADOOP-9124.patch, HADOOP-9124.patch, HADOOP-9124.patch,
> HADOOP-9124.patch
>
>
> This issue is similar to HADOOP-7153. It was found when using MRUnit - see
> MRUNIT-158, specifically
> https://issues.apache.org/jira/browse/MRUNIT-158?focusedCommentId=13501985&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13501985
> --
> o.a.h.io.SortedMapWritable implements the java.util.Map interface, however it
> does not define an implementation of the equals() or hashCode() methods;
> instead the default implementations in java.lang.Object are used.
> This violates the contract of the Map interface which defines different
> behaviour for equals() and hashCode() than Object does. More information
> here:
> http://download.oracle.com/javase/6/docs/api/java/util/Map.html#equals(java.lang.Object)
> The practical consequence is that SortedMapWritables containing equal entries
> cannot be compared properly. We were bitten by this when trying to write an
> MRUnit test for a Mapper that outputs MapWritables; the MRUnit driver cannot
> test the equality of the expected and actual MapWritable objects.
--
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
