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JIRA:  https://issues.apache.org/jira/browse/KAFKA-5793 and https://issues.apache.org/jira/browse/KAFKA-5794

Release Version : 1.0.0

Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).

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Finally, the the RecordMetadata.offset and RecordMetadata.timestamp methods may throw the new RecordMetadataNotAvailableException if the broker was unable to return the metadata for the record in question.  Before this change, producers with acks=0 would return -1 for both the offset() and timestamp() methods. With this KIP, these methods would raise the RecordMetadataNotAvailableException instead. Additionally, messages written to topics with message format versions 0 and 1 would not have a timestamp, and the timestamp() method would have returned -1 before this KIP. It will now raise a RecordMetadataNotAvailableException instead.

Rejected Alternatives

This KIP contains changes to fix existing problems or clarify existing behavior. As such, there are not too many options for making these improvements within the existing solutions. 

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