Error Messages:

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'indexController': Unsatisfied dependency expressed through field 'indexService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'indexServiceImpl': Unsatisfied dependency expressed through field 'userService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userServiceImpl': Unsatisfied dependency expressed through field 'baseMapper'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'userMapper' defined in file [I:\LX\aci_parent\service\service_acl\target\classes\com\lianxi\aclservice\mapper\UserMapper.class]: Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [com/baomidou/mybatisplus/autoconfigure/MybatisPlusAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [I:\LX\aci_parent\service\service_acl\target\classes\com\lianxi\aclservice\mapper\xml\PermissionMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'file [I:\LX\aci_parent\service\service_acl\target\classes\com\lianxi\aclservice\mapper\xml\PermissionMapper.xml]'. Cause: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'com.atguigu.aclservice.entity.Permission'.  Cause: java.lang.ClassNotFoundException: Cannot find class: com.atguigu.aclservice.entity.Permission

There are various cases of this error, one is that your mysql configuration is wrong, one is that your SQL statement or entity class is not correct. Another is that the xml mapping path is not correct.