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When a message is redelivered the DeadLetterChannel will append a customizable header to the message to indicate how many times its been redelivered.
In Camel 1.x: The header is org.apache.camel.redeliveryCount.
In Camel 2.0: The header is CamelRedeliveryCounter, which is also defined on the Exchange.REDELIVERY_COUNTER.
In Camel 2.6: The header CamelRedeliveryMaxCounter, which is also defined on the Exchange.REDELIVERY_MAX_COUNTER, contains the maximum redelivery setting. This header is absent if you use retryWhile or have unlimited maximum redelivery configured.
And a boolean flag whether it is being redelivered or not (first attempt)
In Camel 1.x: The header org.apache.camel.Redelivered contains a boolean if the message is redelivered or not.
In Camel 2.0: The header CamelRedelivered contains a boolean if the message is redelivered or not, which is also defined on the Exchange.REDELIVERED.
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