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https://issues.apache.org/jira/browse/PIG-2815?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13415522#comment-13415522
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Jonathan Coveney commented on PIG-2815:
---------------------------------------

Committed. Thanks Raghu! Also: want to make a ticket for that ObjectSerializer 
CLASSPATH issue you mentioned?
                
> class loader management in PigContext
> -------------------------------------
>
>                 Key: PIG-2815
>                 URL: https://issues.apache.org/jira/browse/PIG-2815
>             Project: Pig
>          Issue Type: Bug
>          Components: impl
>    Affects Versions: 0.9.0
>            Reporter: Raghu Angadi
>            Assignee: Raghu Angadi
>             Fix For: 0.11
>
>         Attachments: PIG-2815.patch, PIG-2815.patch
>
>
> The way {{PigContext.classloader}} and resolveClassName() are managed can 
> lead to strange class loading issues, especially when not all {{register}} 
> statements are at the top (example in the first comment).
> Two factors contribute to this: sometimes only one of them and sometimes 
> together:
>  # a new classloader (CL) is created after registering each jar.
>     ** but the new jar's parent is the root CL rather than previous CL, 
> effectively throwing previous CL away.
>  # resolveClassName() caches classes based on just the name
>     ** A class is not defined by name alone. Classes loaded by two different 
> unrelated CLs are different objects even if both extract the class from same 
> physical jar file.
>     ** because of (1), the cached class is not necessarily same as the class 
> that would be loaded based on 'current' CL
> having different class objects for same class have many subtle side effects. 
> e.g. there would be two instances of static variables. 
> I think both should be fixed.. thought fixing one of them might be good 
> enough in many cases. I will add a patch.
>        

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