Stateful Iterators Java

Posted by Gitmo on Stack Overflow See other posts from Stack Overflow or by Gitmo
Published on 2012-03-31T17:13:38Z Indexed on 2012/03/31 17:29 UTC
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What is a Stateful Iterator?

This question relates to an Iterator defined in Hadoop for performing Joins. As the reference documentation states:

This defines an interface to a stateful Iterator that can replay elements added to it directly. Note that this does not extend Iterator.

What does 'replay elements added to it directly' mean? How is this iterator different from a usual iterator?

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