Available as of Camel 2.15
The scheduler: component is used to generate message exchanges when a scheduler fires. This component is similar to the Timer component, but it offers more functionality in terms of scheduling. Also this component uses JDK
ScheduledExecutorService. Where as the timer uses a JDK
You can only consume events from this endpoint.
name is the name of the scheduler, which is created and shared across endpoints. So if you use the same name for all your timer endpoints, only one scheduler thread pool and thread will be used - but you can configure the thread pool to allow more concurrent threads.
You can append query options to the URI in the following format,
Note: The IN body of the generated exchange is
|Milliseconds before the first poll starts|
Milliseconds before the next poll
|time unit for |
|Controls if fixed delay or fixed rate is used. See ScheduledExecutorService in JDK for details.|
|A pluggable |
|The consumer logs a start/complete log line when it polls. This option allows you to configure the logging level for that.|
|If the polling consumer did not poll any files, you can enable this option to send an empty message (no body) instead.|
|If greedy is enabled, then the ScheduledPollConsumer will run immediately again, if the previous run polled 1 or more messages.|
|Allow to plugin a custom |
|To configure additional properties when using a custom |
|To let the scheduled polling consumer backoff if there has been a number of subsequent idles/errors in a row. The multiplier is then the number of polls that will be skipped before the next actual attempt is happening again. When this option is in use then |
|The number of subsequent idle polls that should happen before the |
|The number of subsequent error polls (failed due some error) that should happen before the |
When the timer is fired, it adds the following information as properties to the
The value of the
The time when the consumer fired.
To set up a route that generates an event every 60 seconds:
And the route in Spring DSL:
Forcing the scheduler to trigger immediately when completed
To let the scheduler trigger as soon as the previous task is complete, you can set the option greedy=true. But beware then the scheduler will keep firing all the time. So use this with caution.
Forcing the scheduler to be idle
There can be use cases where you want the scheduler to trigger and be greedy. But sometimes you want "tell the scheduler" that there was no task to poll, so the scheduler can change into idle mode using the backoff options. To do this you would need to set a property on the exchange with the key
Exchange.SCHEDULER_POLLED_MESSAGES to a boolean value of false. This will cause the consumer to indicate that there was no messages polled.
The consumer will otherwise as by default return 1 message polled to the scheduler, every time the consumer has completed processing the exchange.