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https://issues.apache.org/jira/browse/KAFKA-3563?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15246540#comment-15246540
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ASF GitHub Bot commented on KAFKA-3563:
---------------------------------------
Github user asfgit closed the pull request at:
https://github.com/apache/kafka/pull/1226
> Maintain MessageAndMetadata constructor compatibility
> ------------------------------------------------------
>
> Key: KAFKA-3563
> URL: https://issues.apache.org/jira/browse/KAFKA-3563
> Project: Kafka
> Issue Type: Improvement
> Affects Versions: 0.10.0.0
> Reporter: Grant Henke
> Assignee: Grant Henke
> Fix For: 0.10.1.0
>
>
> The MessageAndMetadata constructor was changed to include timestamp
> information as a part of KIP-32. Though the constructor may not be used in
> general client usage, it may be used in unit tests or some advanced usage. We
> should maintain compatibility if possible.
> One example where the constructor is used is Apache Spark:
> https://github.com/apache/spark/blob/master/external/kafka/src/main/scala/org/apache/spark/streaming/kafka/KafkaRDD.scala#L223-L225
> The old constructor was:
> {code}
> MessageAndMetadata[K, V](topic: String,
> partition: Int,
> private val rawMessage: Message,
> offset: Long,
> keyDecoder: Decoder[K], valueDecoder: Decoder[V])
> {code}
> And after KIP-32 it is now:
> {code}
> MessageAndMetadata[K, V](topic: String,
> partition: Int,
> private val rawMessage: Message,
> offset: Long,
> timestamp: Long = Message.NoTimestamp,
> timestampType: TimestampType = TimestampType.CREATE_TIME,
> keyDecoder: Decoder[K], valueDecoder: Decoder[V])
> {code}
> Even though _timestamp_ and _timestampType_ have defaults, if _keyDecoder_
> and _valueDecoder_ were not accessed by name, then the new constructor is not
> backwards compatible.
> We can fix compatibility by moving the _timestamp_ and _timestampType_
> parameters to the end of the constructor, or by providing a new constructor
> without _timestamp_ and _timestampType_ that matches the old constructor.
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