Someone said they wanted to see: org.springframework.beans.factory.UnsatisfiedDependencyException exception solution, so today, he is here! ! ! !
When you first started working on SpringBoot, you were high-spirited and unmotivated. With the great goal of abandoning the cumbersome configuration of traditional MVC, you eagerly embraced the SpringBoot framework model because you know the core of springboot: agreement is greater than configuration!
So you created the project, entity class, mapper, service, impl, and startup class. The operation is as fierce as a tiger. After clicking the startup button, oh wow, various errors are reported that make people want to die…
Like this
org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'deptsController': Unsatisfied dependency expressed through field 'deptService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name ' deptServiceImpl': Unsatisfied dependency expressed through field 'deptDao'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'deptDao' defined in file [E:Projectspringcloudspringcloud-provider-dept-8001 argetclassescomspringcloudmapperDeptDao.class] : Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Property 'sqlSessionFactory' or 'sqlSessionTemplate' are required 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.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.springcloud.Dept_Provider_8001_Application.main(Dept_Provider_8001_Application.java:18) [classes/:na] Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'deptServiceImpl': Unsatisfied dependency expressed through field 'deptDao'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name ' deptDao' defined in file [E:Projectspringcloudspringcloud-provider-dept-8001 argetclassescomspringcloudmapperDeptDao.class]: Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Property 'sqlSessionFactory' or 'sqlSessionTemplate' are required 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$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:277) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1251) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1171) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:593) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] ... 19 common frames omitted Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'deptDao' defined in file [E:Projectspringcloudspringcloud-provider-dept-8001 argetclassescomspringcloudmapperDeptDao.class]: Invocation of init method failed; nested exception is java. lang.IllegalArgumentException: Property 'sqlSessionFactory' or 'sqlSessionTemplate' are required at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1778) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:593) ~[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$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:277) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1251) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1171) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:593) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] ... 32 common frames omitted Caused by: java.lang.IllegalArgumentException: Property 'sqlSessionFactory' or 'sqlSessionTemplate' are required at org.springframework.util.Assert.notNull(Assert.java:198) ~[spring-core-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.mybatis.spring.support.SqlSessionDaoSupport.checkDaoConfig(SqlSessionDaoSupport.java:74) ~[mybatis-spring-1.3.2.jar:1.3.2] at org.mybatis.spring.mapper.MapperFactoryBean.checkDaoConfig(MapperFactoryBean.java:73) ~[mybatis-spring-1.3.2.jar:1.3.2] at org.springframework.dao.support.DaoSupport.afterPropertiesSet(DaoSupport.java:44) ~[spring-tx-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1837) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1774) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE] ... 42 common frames omitted
You curled your lips, your wise brain began to spin, and you thought to yourself:
1. It may be that the implementation class does not have the @Servcie annotation added. After you add it, click Start, and the error still persists. Heartbreak x1
2. It may be that @MapperScan(“com.xxx.mapper”) is not added to the startup class. After you add it, click Start, and the error still persists. Heartbreak x2
3. It may be that the dao package in ServiceImpl has not imported @Autowired. After you add it, click Start, but the error still persists. Heartbreak x3
How about it? Do you feel like you are in a state of ecstasy and have endless fun?
In the end, you have listed 3 possibilities, but you still need one more note:
@EnableAutoConfiguration
The main functions of @EnableAutoConfiguration are:
Enable automatic configuration of the Spring application context and try to guess and configure the beans you may need. Autoconfiguration classes are typically applied based on the classpath and defined beans. For example, if you have tomcat-embedded.jar in your classpath, you will probably want a TomcatEmbeddedServletContainerFactory (unless you define your own EmbeddedServletContainerFactory bean).
When using SpringBootApplication, the automatic configuration of the context is automatically enabled and this annotation is added, so there is no additional effect.
Automatic configuration attempts to be as intelligent as possible and will back up as you define more of your own configurations. You can always manually exclude() any configuration that you don’t want applied (if you don’t have access to them). You can also exclude them via spring.autoconfigure. Exclude attributes. After the user-defined bean is registered, auto-configuration is always applied.
Packages of classes annotated with @enableautoconfiguration, usually via @springbootapplication, have special meaning and are often used as “default”. For example, it will be used to scan @entity classes. It is generally recommended to place @enableautoconfiguration in the root package (if you are not using @springbootapplication) so that all sub-packages and classes can be searched.
Autoconfiguration classes are regular Spring configuration beans. They are located using the SpringFactoriesLoader mechanism (keying the class). Typically, auto-configured beans are “conditional beans” (usually annotated with @conditionalonclass and @conditionalonmissingbean).
A lot of explanations about @EnableAutoConfiguration annotations above were copied by the blogger from elsewhere. If it is a bit difficult to understand, you only need to know that it is an automatic assembly tool for Beans. Maybe you will ask, why should I do this? Can’t I use @Import directly in my project? Of course, since it is automatically configured, of course you want it to be loaded when the project starts.
Well friends, this lecture on “Postpartum Care of Sows” has ended. Thank you all for watching and listening. See you in the next one!
Every time you like it, I will treat it as a like.