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https://issues.apache.org/jira/browse/ACCUMULO-759?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13452966#comment-13452966
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Billie Rinaldi commented on ACCUMULO-759:
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> However, the boolean is more restrictive than this, because it prevents
> insertion of an iterator at other points in the scan.
No, the boolean method could be used along with two Scanner methods:
{code:java}
something(IteratorSetting) // user handles priority, boolean set to false
something(ScanIteratorSetting) // priority is handled automatically, boolean
set to true
{code}
which is not to say that I'm convinced this is the way to do it. I kind of
like the port-like method you suggest, but it does break some things people
were doing before (mainly setting an iterator at priority Integer.MAX_VALUE),
so I wanted to suggest a method that would not.
> remove priority setting for scan-time iterators
> -----------------------------------------------
>
> Key: ACCUMULO-759
> URL: https://issues.apache.org/jira/browse/ACCUMULO-759
> Project: Accumulo
> Issue Type: Improvement
> Reporter: Adam Fuchs
> Labels: newbie
>
> Iterators have a priority setting that allows a user to order iterators
> arbitrarily. However that priority is an integer that doesn't directly convey
> the iterator's relationship to other iterators. I would postulate that nobody
> has ever needed to sneak in a scan-time iterator underneath a configured
> table iterator (please let me know if I'm wrong about this), and the effect
> of doing so is not easy to calculate. Many people have chosen a bad iterator
> priority and seen commutativity problems with previously configured iterators.
> I propose that we use more of an agglomerative approach to configuring
> scan-time iterators, in which the order of the iterator tree is the same
> order in which the addScanIterator method is called, and all scan-time
> iterators apply after the configured iterators apply. The change to the API
> should just be to remove the priority number, and the existing
> IteratorSetting constructor and accessors should be deprecated.
> With this change, we can think of an iterator as more of a functional
> modification to a data set, as in T' = f(T) or T'' = g(f(T)). This should
> make it easier for developers to use iterators correctly.
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