bean注入失败，报错如下：

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'AAAImpl': Injection of resource dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'BBBImpl': Injection of resource dependencies failed; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'FFFImpl': Unsatisfied dependency expressed through field 'nnService'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'xxxService': Lookup method resolution failed; nested exception is java.lang.IllegalStateException: Failed to introspect Class [XXXService] from ClassLoader [sun.misc.Launcher$AppClassLoader@58644d46]
	at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessProperties(CommonAnnotationBeanPostProcessor.java:332)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1431)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:619)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542)
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335)
	at org.springframework.beans.factory.support.AbstractBeanFactory$$Lambda$246/2091160281.getObject(Unknown Source)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208)
	at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1391)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1311)
	at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.autowireResource(CommonAnnotationBeanPostProcessor.java:544)
	at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.getResource(CommonAnnotationBeanPostProcessor.java:520)
	at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor$ResourceElement.getResourceToInject(CommonAnnotationBeanPostProcessor.java:673)
	at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:228)
	at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:119)
	at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessProperties(CommonAnnotationBeanPostProcessor.java:329)
	... 87 more

1. 检查最后一行报错的XXXService，里面注入的service类，是否互相注入
2. 检查注入的对象名是否为类名一致（首字母小写）
   只使用@Autowired时,需要保证注解的对象名和注解类名一致,
   注意: 首字母要小写,且注解时没有命名

解决：
方法1：优化代码，去掉互相注入的情况
方法2：使用注解，@Lazy(true)