Eureka关闭出现BeanCreationNotAllowedException

在使用Spring Boot 1.5.6 、 Spring Cloud Dalston SR2 和 Spring Cloud Feign 时，会出先当关闭程序，即关闭Eureka Client时，会抛出以下异常：

org.springframework.beans.factory.BeanCreationNotAllowedException: Error creating bean with name 'eurekaAutoServiceRegistration': Singleton bean creation not allowed while singletons of this factory are in destruction (Do not request a bean from a BeanFactory in a destroy method implementation!)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:216) [spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1078) [spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.event.ApplicationListenerMethodAdapter.getTargetBean(ApplicationListenerMethodAdapter.java:283) ~[spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.event.ApplicationListenerMethodAdapter.doInvoke(ApplicationListenerMethodAdapter.java:253) ~[spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.event.ApplicationListenerMethodAdapter.processEvent(ApplicationListenerMethodAdapter.java:177) ~[spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.event.ApplicationListenerMethodAdapter.onApplicationEvent(ApplicationListenerMethodAdapter.java:140) ~[spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:167) ~[spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) ~[spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:393) [spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:399) [spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:347) [spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.doClose(AbstractApplicationContext.java:991) [spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.close(AbstractApplicationContext.java:958) [spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.cloud.context.named.NamedContextFactory.destroy(NamedContextFactory.java:76) [spring-cloud-context-1.2.3.RELEASE.jar:1.2.3.RELEASE]
	at org.springframework.beans.factory.support.DisposableBeanAdapter.destroy(DisposableBeanAdapter.java:272) [spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.destroyBean(DefaultSingletonBeanRegistry.java:578) [spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.destroySingleton(DefaultSingletonBeanRegistry.java:554) [spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.destroySingleton(DefaultListableBeanFactory.java:961) [spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.destroySingletons(DefaultSingletonBeanRegistry.java:523) [spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.destroySingletons(FactoryBeanRegistrySupport.java:230) [spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.destroySingletons(DefaultListableBeanFactory.java:968) [spring-beans-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.destroyBeans(AbstractApplicationContext.java:1030) [spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.doClose(AbstractApplicationContext.java:1006) [spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.context.support.AbstractApplicationContext.close(AbstractApplicationContext.java:958) [spring-context-4.3.10.RELEASE.jar:4.3.10.RELEASE]
	at org.springframework.boot.actuate.endpoint.ShutdownEndpoint$1.run(ShutdownEndpoint.java:74) [spring-boot-actuator-1.5.6.RELEASE.jar:1.5.6.RELEASE]
	at java.lang.Thread.run(Thread.java:748) [na:1.8.0_131]

当ApplicationContext关闭时，它会破坏所有一次性bean。
在这种情况下：
FeignContext实现DisposableBean接口
InetUtils实现AutoCloseable接口
EurekaServiceRegistry有一个公开的关闭方法
所以他们都被认为是一次性bean。
由于EurekaAutoServiceRegistration依赖于于InetUtils和EurekaServiceRegistrybean，所以如果上述任何一个bean被销毁，EurekaAutoServiceRegistration将被销毁。
销毁遵循先进先出的顺序。
通常，应用程序代码不依赖于InetUtils或EurekaServiceRegistry，但它们依赖于FeignClient接口。这意味着，FeignContext通常会在InetUtils和EurekaServiceRegistry之前被创建，所以它会在他们之后被销毁：

当InetUtils或者EurekaServiceRegistry销毁时，
EurekaAutoServiceRegistration首先销毁，
销毁InetUtils和EurekaServiceRegistry。
当销毁FeignContext时将关闭ApplicationContext与FeignClients相关的所有内容。
EurekaAutoServiceRegistration监听ContextClosedEvent，但EurekaAutoServiceRegistration已被摧毁。ApplicationContext将尝试再次创建它，得到上述异常。

解决方案是确保在InetUtils和EurekaServiceRegistry在之前生成FeignContext：

@Component
public class FeignBeanFactoryPostProcessor implements BeanFactoryPostProcessor {

    @Override
    public void postProcessBeanFactory(ConfigurableListableBeanFactory beanFactory) throws BeansException {
        BeanDefinition bd = beanFactory.getBeanDefinition("feignContext");
        bd.setDependsOn("eurekaServiceRegistry", "inetUtils");
    }
}