【异常】expected at least 1 bean which qualifies as autowire candidate for this depende

 1.查看接口实现类是否加入注解，如service、repository等

  2.查看spring配置文件是否自动扫描包    <context:component-scan base-package="xxx.xx.xxx">

  3.查看是否在web.xml中加载spring容器

  4.service是否有实现impl