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https://issues.apache.org/jira/browse/SQOOP-2632?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Dian Fu updated SQOOP-2632:
---------------------------
    Attachment: SQOOP-2632.001.patch

> Sqoop2: add partition class to FROM
> -----------------------------------
>
>                 Key: SQOOP-2632
>                 URL: https://issues.apache.org/jira/browse/SQOOP-2632
>             Project: Sqoop
>          Issue Type: Sub-task
>            Reporter: Dian Fu
>            Assignee: Dian Fu
>             Fix For: 1.99.7
>
>         Attachments: SQOOP-2632.001.patch
>
>
> Each {{SqoopMapper}} will process one {{SqoopSplit}}. {{SqoopSplit}} is 
> instantiated by the MR framework. Let's suppose that MR framework loads 
> {{SqoopSplit}} using classloader A. As {{SqoopSplit}} has one field 
> {{partition}}, so when {{SqoopSplit}} is loaded by classloader A, class 
> {{Partition}} will also be loaded by classloader A and field {{partition}} 
> will be of type {{A.Partition}}. 
> In {{SqoopMapper}}, we will call {{extractor.extract(extractorContext, 
> fromConfig, fromJob, partition)}}. To provide classpath isolation, we will 
> load class {{Extractor}} with a custom classloader {{B}}, so the 
> {{Partition}} class in {{Extractor}} will be loaded by classloader {{B}} by 
> default. This will cause type miss-match between {{A.Partition}} and 
> {{B.Partition}}.
> To resolve this issue, we need to make sure class {{Partition}} not be loaded 
> by the custom classloader {{B}}. To do this, we need provide a method to let 
> {{SqoopMapper}} know the class name of {{Partition}}.



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