异常报文：
Field adminDAO in com......service.impl.AdminServiceImpl required a bean of type 'com.....dao.AdminDAO' that could not be found.
. ____ _ __ _ _ /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \ ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/ ___)| |_)| | | | | || (_| | ) ) ) ) ' |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: (v2.1.5.RELEASE) 2019-05-25 23:39:27.645 INFO 31864 --- [ main] com.eszb.SprintbootdemoApplication : Starting SprintbootdemoApplication on DESKTOP-6MD93CN with PID 31864 (D:\java\springboot-project\sprintbootdemo\target\classes started by Mr.Yu in D:\java\springboot-project\sprintbootdemo) 2019-05-25 23:39:27.649 INFO 31864 --- [ main] com.eszb.SprintbootdemoApplication : No active profile set, falling back to default profiles: default 2019-05-25 23:39:28.523 INFO 31864 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http) 2019-05-25 23:39:28.540 INFO 31864 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat] 2019-05-25 23:39:28.540 INFO 31864 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.19] 2019-05-25 23:39:28.639 INFO 31864 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext 2019-05-25 23:39:28.639 INFO 31864 --- [ main] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 949 ms 2019-05-25 23:39:28.678 WARN 31864 --- [ main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'adminController': Unsatisfied dependency expressed through field 'adminService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'adminService': Unsatisfied dependency expressed through field 'adminDAO'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.eszb.dao.AdminDAO' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)} 2019-05-25 23:39:28.681 INFO 31864 --- [ main] o.apache.catalina.core.StandardService : Stopping service [Tomcat] 2019-05-25 23:39:28.692 INFO 31864 --- [ main] ConditionEvaluationReportLoggingListener : Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled. 2019-05-25 23:39:28.763 ERROR 31864 --- [ main] o.s.b.d.LoggingFailureAnalysisReporter : *************************** APPLICATION FAILED TO START *************************** Description: Field adminDAO in com.eszb.service.impl.AdminServiceImpl required a bean of type 'com.eszb.dao.AdminDAO' that could not be found. The injection point has the following annotations: - @org.springframework.beans.factory.annotation.Autowired(required=true) Action: Consider defining a bean of type 'com.eszb.dao.AdminDAO' in your configuration. Process finished with exit code 1问题描述：这个异常描述是在service类里面用到的dao层接口，在注入dao层接口的时候，出现了异常，没有找到dao层的这个类，这个是由于spring没有扫到dao层的接口的原因，所以需要在启动的类上加上扫描dao层的类的注解，如下：
@MapperScan("com.eszb.dao")此时就ok了
