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#Async not working for method having return type void

I wanted to make a method writing to DB as async using #Async annotation.
I marked the class with the annotation #EnableAsync:
#EnableAsync
public class FacialRecognitionAsyncImpl {
#Async
public void populateDataInPushQueue(int mediaId, int studentId) {
//myCode
}
}
while calling the populateDataInPushQueue method, the write operation should be executed in another thread and the flow should continue from the class I am calling this method. But this is not happening and the program execution is waiting for this method to complete.

The #Async annotation has few limitations - check whether those are respected:
it must be applied to public methods only
it cannot be called from the same class as defined
the return type must be either void or Future
The following can be found at the documentation of #EnableAsync:
Please note that proxy mode allows for the interception of calls through the proxy only; local calls within the same class cannot get intercepted that way.
Another fact is that the class annotated with #EnableAsync must be a #Configuration as well. Therefore start with an empty class:
#EnableAsync
#Configuration
public class AsyncConfiguration { }

In my opinion, you are missing #Configuration annotation and your async service is not component scanned. Here is an example code fragment that should do the trick:
#Configuration
#EnableAsync //should be placed together.
public class FacialRecognitionAsyncService {
#Async
public void populateDataInPushQueue(int mediaId, int studentId) {
//myCode
}
}
#Configuration
#EnableAsync
public class FacialServiceConfig {
// this will make your service to be scanned.
#Bean
public FacialRecognitionAsyncService createFacialRecognitionService() {
return new FacialRecognitionAsyncService();
}
}
Now the service bean that is invoking the async method. Notice that it has been dependency injected. This way spring AOP proxies will be invoked on each invocation fo the facialService. Spring uses AOP in the back scenes in order to implement #Async.
#Service
public class MyBusinessService {
#Autowire
FacialRecognitionAsyncService facialService;
public myBusinessMethod() {
facialService.populateDataInPushQueue()
}
Notice that FacialService is injected in MyService through dependency injection.

Spring + AspectJ pointcut on CrudRepository and Annotation

I have #Tenantable annotation to decide for pointCut :
#Target({ElementType.TYPE, ElementType.METHOD})
#Retention(RetentionPolicy.RUNTIME)
#Inherited
public #interface Tenantable {
}
this my aspect :
#Slf4j
#Aspect
#Configuration
public class TenancyAspect {
#Pointcut("execution(public * *(..))")
public void publicMethod() {}
#Around("publicMethod() && #within(com.sam.example.aspect.aspectexample.model.Tenantable)")
public Object tenatable(ProceedingJoinPoint joinPoint) throws Throwable {
System.out.println("my operations ...");
return joinPoint.proceed();
}
}
This is working without any problem for this service class :
#Tenantable
#Service
public class MyService(){
public void doSomething(){
...
}
}
my aspect is running when I call doSomething() method, It is ok but I want to implement aspect for CrudRepository interface that belongs spring data.
I have changed my Aspect to achieve this like below :
#Slf4j
#Aspect
#Configuration
public class TenancyAspect {
#Pointcut("execution(public * *(..))")
public void publicMethod() {}
#Pointcut("this(org.springframework.data.repository.Repository)")
public void repositoryExec(){}
#Around("publicMethod() && repositoryExec() && #within(com.sam.example.aspect.aspectexample.model.Tenantable)")
public Object tenatable(ProceedingJoinPoint joinPoint) throws Throwable {
System.out.println("my operations ...");
return joinPoint.proceed();
}
}
this is repository :
#Tenantable
#Repository
public interface MyRepository extends CrudRepository{
}
But it doesn't work when I call any method inside of MyRepository.
Is there anyway to do this?
Edit :
It works for all repositories when I apply these :
#Pointcut("execution(public * org.springframework.data.repository.Repository+.*(..))")
and exclude this :
#within(com.sam.example.aspect.aspectexample.model.Tenantable)
But I need this anotation to apply it for specific repositories.

Having taken another look, I think I know what is going on here: You are assuming that just because you made your annotation #Inherited, it will be inherited by implementing classes if you annotate an interface. But this assumption is wrong. #Inherited only works in exactly one case: when extending an annotated base class. It does not work for annotated interfaces, methods etc. This is also documented here:
Note that this meta-annotation type has no effect if the annotated type is used to annotate anything other than a class. Note also that this meta-annotation only causes annotations to be inherited from superclasses; annotations on implemented interfaces have no effect.
As soon as you annotate your implementing class, it works.

Your repositoryExec pointcut should end with + to advice all subclass of Repository
#Pointcut("this(org.springframework.data.repository.Repository+)")

#Asyn annotation with Spring

I am trying to use #Async annotation provided by spring. Going through some of the blogs I found there are the following constraints for using it:
It must be applied to public methods only
Self-invocation – calling the async method from within the same class – won’t work
I have a method which is getting called from the same class which I want to mark #Async. Is there any way of achieving it from the same class?

In Spring v4.3+ you can use self injection, and call the method on the self injected reference.
So for example:
#Component
public class SomeClass {
#Autowired
private SomeClass selfInjected;
public void someMethod() {
selfInjected.someOtherMethod();
}
#Async
public void someOtherMethod(){
...;
}
}
Updated as OP is using version before 4.3:
This will work for you.
#Component
public class SomeClass {
#Autowired
private ApplicationContext applicationContext;
private SomeClass selfInjected;
#PostConstruct
private void init() {
selfInjected = applicationContext.getBean(SomeClass.class);
}
}
Or
The other option is to extract the method to separate class and autowire it. I would personally explore this option before doing the above method.

Unit testing compile-time weaving

I am using the aspectj maven plugin to weave Aspects at compile time. When I run the application, the class with the #Advice annotation is being instantiated just before the first time the advice is called. For example:
#Aspect
public class MyAdviceClass {
public MyAdviceClass() {
System.out.println("creating MyAdviceClass");
}
#Around("execution(* *(..)) && #annotation(timed)")
public Object doBasicProfiling(ProceedingJoinPoint pjp, Timed timed) throws Throwable {
System.out.println("timed annotation called");
return pjp.proceed();
}
}
If I have a method using the #Timed annotation, the "creating MyAdviceClass" will be printed the first time that method is called and "timed annotation called" will be printed every time.
I would like to unit test the functionality of the advice by mocking some components in MyAdviceClass however can not do this because MyAdviceClass is instantiated by AspectJ just in time, not through Spring Beans.
What is the best practice method for unit testing something like this?

I have found the solution and would like to post it for anyone else that encounters this. The trick is using factory-method="aspectOf" in your spring bean definition. So using the example above, I would add this line to my applicationContext.xml
<bean class="com.my.package.MyAdviceClass" factory-method="aspectOf"/>
Any my unit test would look something like this:
#RunWith(SpringJUnit4ClassRunner.class)
#ContextConfiguration(locations = "classpath:/META-INF/spring/applicationContext.xml")
public class MyAdviceClassTest {
#Autowired private MyAdviceClass advice;
#Mock private MyExternalResource resource;
#Before
public void setUp() throws Exception {
initMocks(this);
advice.setResource(resource);
}
#Test
public void featureTest() {
// Perform testing
}
}
More details are available here.

Spring aspectj annotation pointcut

I was trying to create an Aspectj pointcut on method annotation but I failed all the time with different approaches. I'm using aspectj autoproxy (I have no other weaving configured in my spring context). My classes look like this:
public interface Intf
{
#SomeAnnotation
void method1() throws SomeExc;
}
public class Impl implements Intf
{
#Override
public void method1() throws SomeExc
{
//...
}
}
#Aspect
public class MyAspect
{
#AfterThrowing(
pointcut = "execution(* *(..)) && #annotation(SomeAnnotation)",
throwing = "error")
public void afterThrowing(JoinPoint jp, Throwable error)
{
System.err.println(error.getMessage());
}
}
#Component
public class Usage
{
#Autowired
Intf intf;
public void doStuff()
{
intf.method1();
}
}
So I'm wondering why the aspectj won't create the pointcut. I managed to make it work using execution(* *(..) throws SomeExc) which does the job for me but I still want to know what I did wrong.
Also since method1 is defined in an interface and I specify the annotation on implementing class, is there a way to make it work this way? Other proxying mechanisms like transaction management/security works this way in other parts of spring right? And if I'm using interface proxying would specifying the pointcut on implementing class create the pointcut? (I guess not since I'm not using cglib)

try to add #Component to MyAspect class
#Component
#Aspect
public class MyAspect {
...

simply mark your aspect method with
#After("#annotation(package.SomeAnnotation)")
Have a look at this for a step by step guide