項目環境：SpringBoot + MyBatis + MySQL + lombok
問題重現：項目啓動時拋出UnsatisfiedDependencyException異常
具體報錯內容：
org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'goodsController' defined in file [H:\xn\demo\SpringBoot-MyProject-zzj\target\classes\com\springboot\controller\GoodsController.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'goodServiceImpl': Unsatisfied dependency expressed through field 'baseMapper'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.springboot.mapper.GoodsMapper' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:769) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:218) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1341) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1187) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$$Lambda$126/1099552523.getObject(Unknown Source) ~[na:na]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:845) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:877) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:743) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:390) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:312) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1214) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1203) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
at com.springboot.Application.main(Application.java:14) [classes/:na]
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'goodServiceImpl': Unsatisfied dependency expressed through field 'baseMapper'; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.springboot.mapper.GoodsMapper' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:596) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:90) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:374) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1411) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:592) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$$Lambda$126/1099552523.getObject(Unknown Source) ~[na:na]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:277) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1251) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1171) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:857) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:760) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
... 20 common frames omitted
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.springboot.mapper.GoodsMapper' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1658) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1217) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1171) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:593) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
... 35 common frames omitted
問題原因：主要看報錯內容中是哪個bean沒有注入，上面這個報錯是由於mapper層沒有注入，找不到mapper的實例導致
解決方式：
在SpringBoot啓動類上加@MapperScan(“mapper接口層的包路徑”)
@Slf4j
@MapperScan({"com.springboot.mapper"})
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
項目對應包結構如下圖：
該錯誤會有多種原因導致，我這只是其中一種，供大家參考！！！
只要找到報錯中沒有注入的bean，將其交由Spring管理後，問題就可解決！！！