I would use option [1], using probably quartz instead of timer. Hadrian
On Apr 4, 2011, at 11:09 AM, Paul Lowry wrote: > Hi, > > I am using Camel 2.4.0 to define routes in XML (Spring configuration > files). I want my route to read all messages from a JMS queue, at > regular intervals. I also want to keep my route as simple as possible, > for easy maintenance. > > When I look for info about this, there's lots of advice but nothing > definitive. Included below are paraphrased versions of the info I found. > > Please advise on which approach is the simplest and/or most reliable. > > Thanks, > Paul > > [1] > > Approach #1: a timer consumer, then a pollEnrich processor to > pull in a JMS message. > > Example: > <route id="RetryTimerRoute"> > <from uri="timer://myTimer?period=3600000"/> > <pollEnrich uri="activemq:queue:MyQueue"/> > ... > </route> > > Note: > It might be necessary to set the pre-fetch value for the JMS connection > to zero, i.e. "activemq:queue:MyQueue?consumer.prefetchSize=0" > > References: > http://camel.apache.org/content-enricher.html > http://camel.apache.org/polling-consumer.html > http://activemq.apache.org/destination-options.html > http://activemq.apache.org/what-is-the-prefetch-limit-for.html > > [2] > > Approach #2: use templates to move messages onto another > queue at regular intervals; then let consumer of that queue process all > messages. > > Example: > public static class MyRetryTimer { > private ConsumerTemplate consumer; > private ProducerTemplate producer; > public void setConsumer(ConsumerTemplate consumer) { > this.consumer = consumer; > } > public void setProducer(ProducerTemplate producer) { > this.producer = producer; > } > public void transferMessagesForRetry() { > // move all messages > while (true) { > String msg = consumer.receive("activemq:queue:MyFirstQueue", > 1000); > if (msg == null) { > // no more messages > break; > } > producer.send("activemq:queue:MySecondQueue", msg); > } > } > } > <bean id="RetryTimer" class="MyRetryTimer"/> > <route id="RetryTimerRoute"> > <from uri="timer://myTimer?period=3600000"/> > <to uri="bean:RetryTimer?method=transferMessagesForRetry"/> > </route> > <route id="RetryRoute"> > <from uri="activemq:queue:MySecondQueue"/> > ... > </route> > > Notes: > How do I inject the consumer & producer? > > References: > http://camel.apache.org/polling-consumer.html > http://fusesource.com/docs/router/2.6/prog_guide/Templates-Consumer.html > > [3] > > Approach #3: define a task executor in spring, and use it to set the > consumer's "taskExecutor" option. This is not well documented. > > Example: > <bean class="org.springframework.core.task.TimerTaskExecutor"> > <!-- some config goes here --> > </bean> > <route id="RetryRoute"> > <from > uri="activemq:queue:MyQueue?taskExecutor=org.springframework.core.task.TimerTaskExecutor"/> > ... > </route> > > Notes: > Is the example correct? How do I configure the spring task executor? > > References: > http://camel.apache.org/jms > http://static.springsource.org/spring/docs/2.5.6/reference/scheduling.html > https://issues.apache.org/jira/browse/CAMEL-3286 > > -- > > EOF > > STRICTLY PRIVATE, CONFIDENTIAL AND PRIVILEGED COMMUNICATION. > > This message (including attachments) may contain information that is > privileged, confidential or protected from disclosure. They are intended > solely for the use of the intended recipient. If you are not the > intended recipient, you are hereby notified that dissemination, > disclosure, copying, distribution, printing, transmission or use of this > message or any information contained in it is strictly prohibited. If > you have received this message from NewBay Software in error, please > immediately notify the sender by reply email and delete this message > from your computer. The content of this e-mail, and any files > transmitted with it, may have been changed or altered without the > consent of the author. Although we have taken steps to ensure that this > email and attachments are free from any virus, we advise that in keeping > with good computing practice the recipient should ensure they are > actually virus free.
