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As for the difference between the two, note a thread pool can increase/shrink dynamically at runtime depending on load, whereas the number of concurrent consumers is always fixed and supported by the Disruptor internally so performance will be higher.

Thread pools

Be aware that adding a thread pool to a Disruptor endpoint by doing something like:

from("disruptor:stageName").thread(5).process(...)

Can wind up with adding a normal BlockingQueue to be used in conjunction with the Disruptor, effectively negating part of the performance gains achieved by using the Disruptor. Instead, it is advices to directly configure number of threads that process messages on a Disruptor endpoint using the concurrentConsumers option.

Sample

In the route below we use the Disruptor to send the request to this async queue to be able to send a fire-and-forget message for further processing in another thread, and return a constant reply in this thread to the original caller.

public void configure() throws Exception {
    from("direct:start")
        // send it to the disruptor that is async
        .to("disruptor:next")
        // return a constant response
        .transform(constant("OK"));

    from("disruptor:next").to("mock:result");
}

Here we send a Hello World message and expects the reply to be OK.

Object out = template.requestBody("direct:start", "Hello World");
assertEquals("OK", out);

The "Hello World" message will be consumed from the Disruptor from another thread for further processing. Since this is from a unit test, it will be sent to a mock endpoint where we can do assertions in the unit test.

Using multipleConsumers

In this example we have defined two consumers and registered them as spring beans.

<!-- define the consumers as spring beans -->
<bean id="consumer1" class="org.apache.camel.spring.example.FooEventConsumer"/>

<bean id="consumer2" class="org.apache.camel.spring.example.AnotherFooEventConsumer"/>

<camelContext xmlns="http://camel.apache.org/schema/spring">
    <!-- define a shared endpoint which the consumers can refer to instead of using url -->
    <endpoint id="foo" uri="disruptor:foo?multipleConsumers=true"/>
</camelContext>

Since we have specified multipleConsumers=true on the Disruptor foo endpoint we can have those two or more consumers receive their own copy of the message as a kind of pub-sub style messaging. As the beans are part of an unit test they simply send the message to a mock endpoint, but notice how we can use @Consume to consume from the Disruptor.

public class FooEventConsumer {

    @EndpointInject(uri = "mock:result")
    private ProducerTemplate destination;

    @Consume(ref = "foo")
    public void doSomething(String body) {
        destination.sendBody("foo" + body);
    }

}

Extracting disruptor information

If needed, information such as buffer size, etc. can be obtained without using JMX in this fashion:

DisruptorEndpoint disruptor = context.getEndpoint("disruptor:xxxx");
int size = disruptor.getBufferSize();