问题原因：

mynatis-plus的jar包版本与springboot3版本不匹配导致报错

主要报错：
sqlSession错误及注入资源依赖项失败

1.Injection of resource dependencies failed
2.Property 'sqlSessionFactory' or 'sqlSessionTemplate' are required

解决办法：

1.mybatis-plus官网中查看版本更新日志https://github.com/baomidou/mybatis-plus/blob/3.0/CHANGELOG.md （点击访问）
2.在最新的更新日志3.5.3中（2022.12.28）得知mybtis-plus的版本是在3.5.3才开始支持springboot2.7以上版本的
3.更换jar版本至最新的，解决成功

总结：

我是在尝试新技术时跟随网上博主的教程进行搭建的，虽然问题已经解决，但是我很奇怪同样的代码人家可以成功，我的确会报错，后面我才发现教程是在3.5.3版本更新以前就有了的…脑壳好多问号 ?_?

该文章仅做为参考，具体问题还得根据不同的情况去分析排查

1.问题出现过程：

问题1

在创建springboot3工程时没有问题，在什么都不加的情况下启动类与测试类都可以正常启动；
但是在加入mybatis-plus的jar包后在启动会先报如下错误，扫描不到包

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

Description:

A component required a bean of type 'com.example.springboot3.mapper.StudentMapper' that could not be found.


Action:

Consider defining a bean of type 'com.example.springboot3.mapper.StudentMapper' in your configuration.


Process finished with exit code 1

问题2

在加上注解mapperScan后又会报以下错误

报错

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentServiceImpl': Injection of resource dependencies failed
	at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessProperties(CommonAnnotationBeanPostProcessor.java:303) ~[spring-context-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1416) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:597) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:520) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:326) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:324) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:200) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:973) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:941) ~[spring-context-6.0.9.jar:6.0.9]
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:608) ~[spring-context-6.0.9.jar:6.0.9]
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:146) ~[spring-boot-3.1.0.jar:3.1.0]
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:733) ~[spring-boot-3.1.0.jar:3.1.0]
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:435) ~[spring-boot-3.1.0.jar:3.1.0]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:311) ~[spring-boot-3.1.0.jar:3.1.0]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1305) ~[spring-boot-3.1.0.jar:3.1.0]
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1294) ~[spring-boot-3.1.0.jar:3.1.0]
	at com.example.springboot3.Springboot3Application.main(Springboot3Application.java:12) ~[classes/:na]
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentMapper' defined in file [F:\Test_Workspace\Springboot3\target\classes\com\example\springboot3\mapper\StudentMapper.class]: Property 'sqlSessionFactory' or 'sqlSessionTemplate' are required
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1770) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:598) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:520) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:326) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:324) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:205) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.resolveBeanByName(AbstractAutowireCapableBeanFactory.java:457) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.autowireResource(CommonAnnotationBeanPostProcessor.java:496) ~[spring-context-6.0.9.jar:6.0.9]
	at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.getResource(CommonAnnotationBeanPostProcessor.java:467) ~[spring-context-6.0.9.jar:6.0.9]
	at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor$ResourceElement.getResourceToInject(CommonAnnotationBeanPostProcessor.java:618) ~[spring-context-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:242) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:133) ~[spring-beans-6.0.9.jar:6.0.9]
	at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessProperties(CommonAnnotationBeanPostProcessor.java:300) ~[spring-context-6.0.9.jar:6.0.9]
	... 17 common frames omitted
Caused by: java.lang.IllegalArgumentException: Property 'sqlSessionFactory' or 'sqlSessionTemplate' are required

2.解决过程：

1.在mybatis-plus官网中查看更新日志，看到相关问题的说明，可以看到是从3.5.3版本才开始支持springboot2.7以上的

2.也可在https://mvnrepository.com/中也对jar包版本进行查看
3.更换jar包，由原来的3.5.1更改为最新的版本3.5.3

启动成功