Book Image

Spring Integration Essentials

By : CHANDAN K PANDEY
Book Image

Spring Integration Essentials

By: CHANDAN K PANDEY

Overview of this book

Table of Contents (18 chapters)
Spring Integration Essentials
Credits
About the Author
Acknowledgments
About the Reviewers
www.PacktPub.com
Preface
Index

Resequencers


A resequencer can be used to enforce an ordered delivery to the next subsystem. It will hold on to a message till all messages numbered before it have been delivered. For example, if messages have been numbered 1 to 10 and if the message numbered 8 arrives sooner than the messages numbered 1 to 7, it will hold it in temporary storage and will be delivered only when the delivery of messages numbered 1 to 7 is complete. The SEQUENCE_NUMBER header of the message is used by resequencer to track the sequences. It can be considered as a special case of aggregator, which holds on to the message based on a header value but does not do any processing on the messages:

<int:resequencer input-channel="fetchedFeedChannelForAggregatior" 
  output-channel="cahinedInputFeedChannel" 
  release-strategy="sofeedResCompletionStrategyBean" 
  release-strategy-method="checkCompleteness" 
  correlation-strategy="soFeedResCorrelationStrategyBean" 
  correlation-strategy-method="groupFeedsBasedOnPublishDate...