Why SimpleJmsListenerContainerFactory did NOT provide concurrency config?

Question

We can see SimpleMessageListenerContainer has property named concurrentConsumers, but SimpleJmsListenerContainerFactory did NOT support to config it. What's the root cause? Do not recommend to use concurrency for SimpleMessageListenerContainer ?

Answer 1

Set the concurrency on the @JmsListener annotation:

/**
 * The concurrency limits for the listener, if any. Overrides the value defined
 * by the container factory used to create the listener container.
 * <p>The concurrency limits can be a "lower-upper" String &mdash; for example,
 * "5-10" &mdash; or a simple upper limit String &mdash; for example, "10", in
 * which case the lower limit will be 1.
 * <p>Note that the underlying container may or may not support all features.
 * For instance, it may not be able to scale, in which case only the upper limit
 * is used.
 */
String concurrency() default "";

Looks like the Javadocs are wrong, though

Overrides the value defined
 * by the container factory used to create the listener container.