hadoop-common-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Harsh J (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HADOOP-8549) Allow other implementation's of java.util.Map in MapWritable
Date Mon, 09 Jul 2012 06:39:34 GMT

    [ https://issues.apache.org/jira/browse/HADOOP-8549?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13409220#comment-13409220
] 

Harsh J commented on HADOOP-8549:
---------------------------------

Patch lacks a few items:

# No javadocs or any other form of dev-docs seem to be present. How would others know how
to use this feature? Lets document it.
# I'm -1 on relying on protected member variables directly, as thats ugly to do. Do something
similar to ArrayWritable instead, where an inheritor passes the class via a constructor. Or
at least provide getter/setter of some form.

The idea is good, but how does it work in terms of portability? If it is written by client
who used X impl. of map, and then read by another client who used Y or the default impl.,
is it guaranteed to work? If yes, lets document that guarantee. And if not, does it throw
a proper error message?

Thanks!
                
> Allow other implementation's of java.util.Map in MapWritable
> ------------------------------------------------------------
>
>                 Key: HADOOP-8549
>                 URL: https://issues.apache.org/jira/browse/HADOOP-8549
>             Project: Hadoop Common
>          Issue Type: Improvement
>          Components: io
>    Affects Versions: 2.0.0-alpha
>            Reporter: madhukara phatak
>            Assignee: madhukara phatak
>            Priority: Minor
>         Attachments: HADOOP-8549.patch
>
>
> Current implementation of MapWritable uses HashMap as Map implementation. But in some
of the use cases we need other implementations of Map like LinkedHashMap,SortedMap.This jira
changes visibility of 'instance' in MapWritable from private to protected which allows us
to inject custom Map implementation through sub classing MapWritable  .  

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators: https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira

        

Mime
View raw message