Enterprise Integration Patterns: Designing, Building, and Deploying Messaging Solutions (Addison-Wesley Signature Series (Fowler))

by Hohpe Gregor

But how does the consumer know when a new message is available? The easiest approach is for the consumer to repeatedly check the channel to see if a message is available. When a message is available, it consumes the message and then goes back to checking for the next one. This process is called polling.