ActiveMQ：如何根据指定的时间段使用队列中的消息

Question

I have a queue and i need to consume the messages based on a specific time period.Let say, for every five minutes i need to start consuming the messages and process them. Currently i am using a timer to trigger the route and process the messages but the below code is not working.

The below code is from my blueprint

Route:

timer value="timer://errorMessageProcessorTimer?period=120000"

errorqueue.in value="activemq:Q.ERROR"

<camelContext xmlns="http://camel.apache.org/schema/blueprint">

    <route id="errorNotificationFilterRoute">
        <from uri="{{timer}}"/>
        <to uri="direct:processErrorMessage"/>
    </route>        

    <route id="processErrorMessage">
        <from uri="direct:processErrorMessage"/>
        <from uri="{{errorqueue.in}}" />
        <log loggingLevel="INFO" logName="errormessage" message="Error Notification Queue reading the error message..." />
        <filter>
            <simple>${body} contains 'xxxxx'</simple>
            <to uri="file:C:\\datafiles\\output"/>
            <log loggingLevel="INFO" logName="errormessage" message="Error message processed succesfully...." />          
        </filter>
   </route>

</camelContext>

Answer 1

It is not possible to have two from Tags in one Route!

Take a look to the Enterprise Integration Patterns . There is something called Throttler. Maybe this helps you.

The Throttler Pattern allows you to ensure that a specific endpoint does not get overloaded, or that we don't exceed an agreed SLA with some external service.

<route id="processErrorMessage">
  <from uri="{{errorqueue.in}}" />
  <!-- throttle 3 messages per 10 sec -->
  <throttle maximumRequestsPerPeriod="3" timePeriodMillis="10000">
  <log loggingLevel="INFO" logName="errormessage" message="Error Notification Queue reading the error message..." />
</route>

Answer 2

See the control bus EIP pattern how you can send a message to a 'controlbus' endpoint and have it start/stop rotues.

• http://camel.apache.org/controlbus.html