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From "Cardon, Tejay E" <>
Subject Custom Iterators
Date Wed, 22 Aug 2012 20:41:20 GMT
I'm interested in writing a custom iterator, and I've been looking for documentation on how
to do so.  Thus far, I've not been able to find anything beyond the java docs in SortedKeyValueIterator
and a few other sub-classes.  A few of the examples use Iterators, but provide no real info
on how to properly implement one.  Is there anywhere to find general guidance on the iterator

(If you're interested)
Specifically, for those that are curious, I'm trying to implement something similar to the
wikisearch example, but with some key differences.  In my case, I've got a file with various
attributes that being indexed.  So for each file there are 5 attributes, and each attribute
has a fixed number of possible values.  For example (totally made up):
personID, gender, hair color, country, race, personRecord

Row:binID; ColFam:Attribute_AttributeValue; ColQ:PersonID; Val:blank
Row:binID; ColFam:"D"; ColQ:personID; value:personRecord

A typical query would be:
Give me the personRecord for all people with:
Gender: male &
Hair color: blond or brown &
Country: USA or England or china or korea &
Race: white or oriental

The existing Iterators used in the wikisearch example are unable to handle the "or" clauses
in each attribute.
The OrIterator doesn't appear to handle the possibility more than one row per tablet

Tejay Cardon

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