Akka 演员无法初始化

Question

我有一个简单的 Spring Boot + Akka 应用程序。 很少应用程序无法启动，并出现指向 actor 创建的错误消息：

<!-- language-all: java -->
akka.actor.ActorInitializationException: akka://AkkaSystem/user/MyActor: exception during creation

我有以下 Spring 和 Akka 配置：

演员类

@Scope(SCOPE_PROTOTYPE)
@Component("MyActor")
public class MyActor extends UntypedActor {
....
}

SpringActorProducer 类

public class SpringActorProducer implements IndirectActorProducer {
    final ApplicationContext applicationContext;
    final String actorBeanName;
    public SpringActorProducer(ApplicationContext applicationContext,
                           String actorBeanName) {
        this.applicationContext = applicationContext;
        this.actorBeanName = actorBeanName;
    }
    @Override
    public Actor produce() {
        return (Actor) applicationContext.getBean(actorBeanName);
    }
    @Override
    public Class<? extends Actor> actorClass() {
        return (Class<? extends Actor>) applicationContext.getType(actorBeanName);
    }
}

AkkaSpringExtension 类

@Component
public class AkkaSpringExtension implements Extension {
    private ApplicationContext applicationContext;

    public void initialize(ApplicationContext applicationContext) {
        this.applicationContext = applicationContext;
    }

    public Props props(String actorBeanName) {
        return Props.create(SpringActorProducer.class, applicationContext, actorBeanName);
    }
}

和配置类

@Configuration
public class AkkaConfiguration {
    @Autowired
    private ApplicationContext applicationContext;

    @Autowired
    private AkkaSpringExtension springExtension;

    @Bean
    public ActorSystem actorSystem() {
        ExecutorService executor = Executors.newCachedThreadPool();
        DelegatingSecurityContextExecutorService executorService = new DelegatingSecurityContextExecutorService(executor);
        ExecutionContext ec = ExecutionContexts.fromExecutorService(executorService);
        ActorSystem system = ActorSystem.create("AkkaSystem", customAkkaConfiguration(), this.getClass().getClassLoader(), ec);

        springExtension.initialize(applicationContext);
        return system;
    }

    @Bean
    public Config customAkkaConfiguration() {
        return ConfigFactory.load();
    }
}

之后，我将在我的服务主体中创建一个演员：

private ActorRef myActor;
@Autowired
private ActorSystem actorSystem;
@Autowired
private AkkaSpringExtension springExtension;

public void afterPropertiesSet() throws Exception {
    myActor = actorSystem.actorOf(springExtension.props("MyActor"), "MyActor");
}

通常一切都按预期工作，但有时会发生异常（可能 20 个服务器启动中的 1 个）：

MyActor[ERROR] [09/19/2016 10:14:07.705] [pool-3-thread-1] [akka://AkkaSystem/user/MyActor] Error creating bean with name 'MyActor': Injection of autowired dependencies failed; nested exception is java.lang.IllegalStateException: About-to-be-created singleton instance implicitly appeared through the creation of the factory bean that its bean definition points to
akka.actor.ActorInitializationException: akka://AkkaSystem/user/MyActor: exception during creation
    at akka.actor.ActorInitializationException$.apply(Actor.scala:174)
    at akka.actor.ActorCell.create(ActorCell.scala:607)
    at akka.actor.ActorCell.invokeAll$1(ActorCell.scala:461)
    at akka.actor.ActorCell.systemInvoke(ActorCell.scala:483)
    at akka.dispatch.Mailbox.processAllSystemMessages(Mailbox.scala:282)
    at akka.dispatch.Mailbox.run(Mailbox.scala:223)
    at org.springframework.security.concurrent.DelegatingSecurityContextRunnable.run(DelegatingSecurityContextRunnable.java:83)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1153)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
    at java.lang.Thread.run(Thread.java:785)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'MyActor': Injection of autowired dependencies failed; nested exception is java.lang.IllegalStateException: About-to-be-created singleton instance implicitly appeared through the creation of the factory bean that its bean definition points to
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:355)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:325)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1076)
    at com.swissre.cih.configuration.akka.SpringActorProducer.produce(SpringActorProducer.java:17)
    at akka.actor.Props.newActor(Props.scala:213)
    at akka.actor.ActorCell.newActor(ActorCell.scala:562)
    at akka.actor.ActorCell.create(ActorCell.scala:588)
    ... 8 more
Caused by: java.lang.IllegalStateException: About-to-be-created singleton instance implicitly appeared through the creation of the factory bean that its bean definition points to
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:378)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1123)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1018)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getSingletonFactoryBeanForTypeCheck(AbstractAutowireCapableBeanFactory.java:865)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getTypeForFactoryBean(AbstractAutowireCapableBeanFactory.java:796)
    at org.springframework.beans.factory.support.AbstractBeanFactory.isTypeMatch(AbstractBeanFactory.java:544)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doGetBeanNamesForType(DefaultListableBeanFactory.java:449)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanNamesForType(DefaultListableBeanFactory.java:425)
    at org.springframework.beans.factory.BeanFactoryUtils.beanNamesForTypeIncludingAncestors(BeanFactoryUtils.java:220)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1199)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1054)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1019)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:566)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:349)
    ... 18 more

有什么想法可以出错吗？

Answer 1

我将actor初始化从afterPropertiesSet移到了一个常规方法，所以actor将在第一次方法调用时被初始化并且初始化失败消失了。