Async method in Spring Boot - rest

Question

I have a problem with sending email with method annotated as #Async.
Firstly, I am not sure if it is possible to work as I want so I need help with explanation.
Here is what am doing now:
In main method i have annotation
#EnableAsync(proxyTargetClass = true)
Next I have AsyncConfig class
import org.springframework.context.annotation.Configuration;
import org.springframework.scheduling.annotation.AsyncConfigurerSupport;
import java.util.concurrent.Executor;
import org.springframework.scheduling.concurrent.ThreadPoolTaskExecutor;
#Configuration
public class AsyncConfig extends AsyncConfigurerSupport {
#Override
public Executor getAsyncExecutor() {
ThreadPoolTaskExecutor executor = new ThreadPoolTaskExecutor();
executor.setCorePoolSize(2);
executor.setMaxPoolSize(2);
executor.setQueueCapacity(500);
executor.setThreadNamePrefix("email-");
executor.initialize();
return executor;
}
}
Of course, its rest application so i have controller, service etc, looks normally, nothing special
My async method looks like this:
#Async
public void sendEmail() throws InterruptedException {
log.info("Sleep");
Thread.sleep(10000L);
//method code
log.info("Done");
}
I executing this method in another service method:
#Override
public boolean sendSystemEmail() {
try {
this.sendEmail();
} catch (InterruptedException e) {
e.printStackTrace();
}
log.info("pending sendEmail method");
return true;
}
Now what I want archive is to ignore executing sendEmail() function and execute return true; meanwhile function sendEmail() will be executing in another Thread. Of course it doesn't work now as I want. Unfortunately.
Note that I am new into async programming, so I have lack of knowledge in some parts of this programming method.
Thanks for any help.

Answer 1

First – let’s go over the rules – #Async has two limitations:
it must be applied to public methods only
self-invocation – calling the async method from within the same class – won’t work
The reasons are simple – the method needs to be public so that it can be proxied. And self-invocation doesn’t work because it bypasses the proxy and calls the underlying method directly.
http://www.baeldung.com/spring-async