How to create a different ThreadPoolTaskExecutor in Spring Boot?

Question

I am now using @EnableAsync and @Async annotation to use multithreaded in Spring Boot. I have service A(fast) and service B(slow).

How can I set different pool for them? So when there are lots of calls for B, the application can still handle service A in a different pool from B.

@Configuration
@EnableAsync
public class ServiceExecutorConfig implements AsyncConfigurer {

    @Override
    public Executor getAsyncExecutor() {
        ThreadPoolTaskExecutor taskExecutor = new ThreadPoolTaskExecutor();
        taskExecutor.setCorePoolSize(30);
        taskExecutor.setMaxPoolSize(40);
        taskExecutor.setQueueCapacity(10);
        taskExecutor.initialize();
        return taskExecutor;

    }
}

Answer 1

First of all, you can define your thread pool executor and use them as a configure them as beans like this -

@Configuration
public class ThreadConfig {
    @Bean
    public TaskExecutor executorA() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        executor.setCorePoolSize(4);
        executor.setMaxPoolSize(4);
        executor.setThreadNamePrefix("default_task_executor_thread");
        executor.initialize();
        return executor;
    } 

    @Bean
    public TaskExecutor executorB() {
        ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
        executor.setCorePoolSize(4);
        executor.setMaxPoolSize(4);
        executor.setThreadNamePrefix("executor-B");
        executor.initialize();
        return executor;
    }
}  

After that, you can specify your executor on method level like this -

@Async("executorA")
public void methodWithVoidReturnType(String s) {
    .....
}

@Async("executorA")
public Future<String> methodWithSomeReturnType() { 
   ...
   try {
      Thread.sleep(5000);
       return new AsyncResult<String>("hello world !!!!");
   } catch (InterruptedException e) {
      ...
   }

   return null;
}