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https://issues.apache.org/jira/browse/ACCUMULO-697?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13419898#comment-13419898
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William Slacum commented on ACCUMULO-697:
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Does this work with client side iterators only? The top level iterator will
usually be running server side, so you'll need to have an interface to set a
serializer for some object at the top of the stack (and possibly another
deserializer if you have custom iterators beneath it) and set a deserializer at
the client level. At some point on the server side, the iterator will have to
transform the user type into a {{byte[]}}, which is basically what a {{Value}}
is. On the client side, the user will still have to supply code to deserialize
the {{byte[]}}, which can already be accomplished with no code changes by using
a library such as Google Collections/Guava or Apache Commons.
> Break Scanner parameterization from Key,Value to Key,{Something}
> ----------------------------------------------------------------
>
> Key: ACCUMULO-697
> URL: https://issues.apache.org/jira/browse/ACCUMULO-697
> Project: Accumulo
> Issue Type: Improvement
> Components: client
> Affects Versions: 1.5.0
> Reporter: Josh Elser
> Assignee: Josh Elser
>
> When writing a custom iterator, many times the iterator has some semantic
> knowledge of what each Key/Value being returned actually means (e.g. A word
> count could be returning Key/Value but really is returning an Integer/Long
> count in the Value). This forces the client to know what is going to be
> returned and handle the cast/transformation.
> I believe it should be fairly straightforward to encapsulate this
> transformation inside the Accumulo client code. I plan on investigating the
> possibility of changing the ScannerBase impl, or perhaps making a
> TypedScannerBase, in which the iterator at the "top" of the stack for a scan
> can return something other than a Value to the client.
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