Spring integration: sftp-inbound-adapter with retry - spring-integration

Question

I implemented a sftp-inbound-adapter which should be launched every day at 2PM and I like doing only one retry after 2 hours if the result is empty (no files received),
How can i do this using the retry mechanism?
My source code is the following:
<int-sftp:inbound-channel-adapter id="sftpInbondAdapter"
auto-startup="true" channel="receiveChannel" session-factory="sftpSessionFactory"
local-directory="file:local-dir" remote-directory="/"
auto-create-local-directory="true" delete-remote-files="false"
filename-regex=".*\.txt$">
<int:poller cron="0 0 14 * * ?"></int:poller>
<int-sftp:request-handler-advice-chain>
<ref bean="retryAdvice" />
</int-sftp:request-handler-advice-chain>
</int-sftp:inbound-channel-adapter>

Answer 1

Starting with 4.2, you can use a Smart Poller to adjust the poll frequency based on whether there was a message or not.
Out of the box, there's the SimpleActiveIdleMessageSourceAdvice which uses a different fixed-delay (via a DynamicPeriodicTrigger) when there's a message Vs. no message.
If you don't like it's algorithm (it uses delays, not a cron expression), you can write a custom subclass of AbstractMessageSourceAdvice.
I am not sure what your retryAdvice bean is, but retry usually only applies if there was an exception.
EDIT
I have created a new advice that's more suitable for you; see the gist here.
You would configure it like this...
...
<int:poller trigger="compoundTrigger">
<int:advice-chain>
<bean class="example.CompoundTriggerAdvice">
<constructor-arg ref="compoundTrigger"/>
<constructor-arg ref="secondary"/>
</bean>
</int:advice-chain>
</int:poller>
...
<bean id="compoundTrigger" class="example.CompoundTrigger">
<constructor-arg ref="primary" />
</bean>
<bean id="primary" class="org.springframework.scheduling.support.CronTrigger">
<constructor-arg value="0 0 14 * * ?" />
</bean>
<bean id="secondary" class="org.springframework.scheduling.support.PeriodicTrigger">
<constructor-arg value="7200000" />
</bean>
When no message is received, we'll use the secondary trigger (2 hours), otherwise, the cron trigger.