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https://issues.apache.org/jira/browse/KAFKA-2295?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14958017#comment-14958017
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Guozhang Wang commented on KAFKA-2295:
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[~omkreddy] Could you rebase the patch again?

> Dynamically loaded classes (encoders, etc.) may not be found by Kafka 
> Producer 
> -------------------------------------------------------------------------------
>
>                 Key: KAFKA-2295
>                 URL: https://issues.apache.org/jira/browse/KAFKA-2295
>             Project: Kafka
>          Issue Type: Bug
>          Components: producer 
>            Reporter: Tathagata Das
>            Assignee: Manikumar Reddy
>            Priority: Blocker
>             Fix For: 0.9.0.0
>
>         Attachments: KAFKA-2295.patch, KAFKA-2295_2015-07-06_11:32:58.patch, 
> KAFKA-2295_2015-08-20_17:44:56.patch
>
>
> Kafka Producer (via CoreUtils.createObject) effectively uses Class.forName to 
> load encoder classes. Class.forName is by design finds classes only in the 
> defining classloader of the enclosing class (which is often the bootstrap 
> class loader). It does not use the current thread context class loader. This 
> can lead to problems in environments where classes are dynamically loaded and 
> therefore may not be present in the bootstrap classloader.
> This leads to ClassNotFound Exceptions in environments like Spark where 
> classes are loaded dynamically using custom classloaders. Issues like this 
> have reported. E.g. - 
> https://www.mail-archive.com/user@spark.apache.org/msg30951.html
> Other references regarding this issue with Class.forName 
> http://stackoverflow.com/questions/21749741/though-my-class-was-loaded-class-forname-throws-classnotfoundexception
> This is a problem we have faced repeatedly in Apache Spark and we solved it 
> by explicitly specifying the class loader to use. See 
> https://github.com/apache/spark/blob/master/core/src/main/scala/org/apache/spark/util/Utils.scala#L178



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