How to use multiple threadPoolExecutor for Async Spring

Question

I am using Spring @Async on two classes. Both are ultimately implementing an interface. I am creating two separate ThreadPoolTaskExecutor so each class has its own ThreadPool to work off of.

However, because I think something with proxy and how Spring implements Async classes, I have to put the @Async annotation on the base interface. Because of this, both classes end up using the same ThreadPoolTaskExecutor.

Is it possible to tell Spring that for this Bean (in this case I am calling the classes that implement that interface a Service), use this ThreadPoolTaskExecutor?

Answer 1

By default when specifying @Async on a method, the executor that will be used is the one supplied to the 'annotation-driven' element as described here.

However, the value attribute of the @Async annotation can be used when needing to indicate that an executor other than the default should be used when executing a given method.

@Async("otherExecutor")
void doSomething(String s) {
    // this will be executed asynchronously by "otherExecutor"
}

In this case, "otherExecutor" may be the name of any Executor bean in the Spring container, or may be the name of a qualifier associated with any Executor, e.g. as specified with the element or Spring’s @Qualifier annotation

https://docs.spring.io/spring/docs/current/spring-framework-reference/html/scheduling.html

And probably you need to specify the otherExecutor bean in you app with the pool settings you wish.

@Bean
public TaskExecutor otherExecutor() {
    ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
    executor.setCorePoolSize(5);
    executor.setMaxPoolSize(10);
    executor.setQueueCapacity(25);

    return executor;
}