springboot 依赖注入异常---问题记录

  循环依赖注入嵌套异常，原因：a依赖b，b依赖c，c依赖a，在使用 @Autowired 就会出现如下异常。

[11:22:17:166] [ERROR] - org.springframework.boot.diagnostics.LoggingFailureAnalysisReporter.report(LoggingFailureAnalysisReporter.java:42) - 

***************************
APPLICATION FAILED TO START
***************************

Description:

The dependencies of some of the beans in the application context form a cycle:

   activityController (field private com.yryj.service.activity.ActivitysIssueService com.yryj.controller.activity.ActivityController.activitysIssueService)
      ↓
   activitysIssueServiceImpl (field private com.yryj.service.user.impl.PublisherImpl com.yryj.service.activity.impl.ActivitysIssueServiceImpl.publisher)
      ↓
   publisherImpl (field com.yryj.service.mutually.MutuallyQMessageService com.yryj.service.user.impl.PublisherImpl.mutuallyQMessageService)
      ↓
   mutuallyQMessageServiceImpl (field private com.yryj.service.message.MessageInformationService com.yryj.service.mutually.impl.MutuallyQMessageServiceImpl.messageInformationService)
      ↓
   messageInformationImpl (field private com.yryj.service.dynamic.state.DynamicStateIssueMessageService com.yryj.service.message.impl.MessageInformationImpl.dynamicStateIssueMessageService)
      ↓
   dynamicStateIssueMessageServiceImpl (field private com.yryj.service.article.issue.ArticleIssueMessageService com.yryj.service.dynamic.state.impl.DynamicStateIssueMessageServiceImpl.articleIssueMessageService)
      ↓
   articleIssueMessageServiceImpl (field private com.yryj.service.answer.issue.AnswersIssueMessageService com.yryj.service.article.issue.impl.ArticleIssueMessageServiceImpl.answersIssueMessageService)
┌─────┐
|  answersIssueMessageServiceImpl defined in file [D:\SVN\zgryrj\target\classes\com\yryj\service\answer\issue\impl\AnswersIssueMessageServiceImpl.class]
└─────┘ 

解决办法：

1.新建接口，防止循环依赖，。

2.尽量依赖注入 mapper 层，也就是数据处理层。