from("rabbitmq://hostname[:port]/myqueue_high")
    .setHeader("priority", constant(9))
    .to("direct:messageProcessing");

from("rabbitmq://hostname[:port]/myqueue_medium")
    .setHeader("priority", constant(5))
    .to("direct:messageProcessing");

from("rabbitmq://hostname[:port]/myqueue_low")
    .setHeader("priority", constant(1))
    .to("direct:messageProcessing");

// sort by priority by allowing duplicates (message can have same priority)
// and use reverse ordering so 9 is first output (most important), and 0 is last
// (of course we could have set the priority the other way around, but this way
// we keep align with the JMS specification...)
// use batch mode and fire every 3th second
from("direct:messageProcessing")
    .resequence(header("priority")).batch().timeout(3000).allowDuplicates().reverse()
    .to("mock:result");

final PriorityBlockingQueueFactory<Exchange> priorityQueueFactory = new PriorityBlockingQueueFactory<Exchange>();
priorityQueueFactory.setComparator(new Comparator<Exchange>() {
    @Override
    public int compare(final Exchange exchange1, final Exchange exchange2) {
        final Integer prio1 = (Integer) exchange1.getIn().getHeader("priority");
        final Integer prio2 = (Integer) exchange2.getIn().getHeader("priority");
        return -prio1.compareTo(prio2);  // 9 has higher priority then 0
    }
});

final SimpleRegistry registry = new SimpleRegistry();
registry.put("priorityQueueFactory", priorityQueueFactory);

final ModelCamelContext context = new DefaultCamelContext(registry);
// configure and start your context here...

from("rabbitmq://hostname[:port]/myqueue_high")
    .setHeader("priority", constant(9))
    .to("seda:priority?queueFactory=#priorityQueueFactory");  // reference queue in registry

from("rabbitmq://hostname[:port]/myqueue_medium")
    .setHeader("priority", constant(5))
    .to("seda:priority?queueFactory=#priorityQueueFactory");

from("rabbitmq://hostname[:port]/myqueue_low")
    .setHeader("priority", constant(1))
    .to("seda:priority?queueFactory=#priorityQueueFactory");

from("seda:priority")
    .to("direct:messageProcessing");