1。mvninstall可重新生成修改测试 2。hrCausedby:org。springframework。beans。factory。NoSuchBeanDefinitionException:Noqualifyingbeanoftype‘com。zyd。mapper。xxMapper’available:expectedatleast1beanwhichqualifiesasautowirecandidate。Dependencyannotations:{org。springframework。beans。factory。annotation。Autowired(requiredtrue)} 由于spring容器没有扫描到对应的信息 在启动类加上,即可MapperScan({com。itheima})packagecom。itheima。springboot8mybatis;importorg。mybatis。spring。annotation。MapperScan;importorg。springframework。boot。SpringApplication;importorg。springframework。boot。autoconfigure。SpringBootApplication;SpringBootApplicationMapperScan({com。itheima})publicclassSpringboot8MybatisApplication{publicstaticvoidmain(String〔〕args){SpringApplication。run(Springboot8MybatisApplication。class,args);}} 3。实例如下packagecom。itheima。dao;importcom。itheima。domain。Book;importorg。apache。ibatis。annotations。Mapper;importorg。apache。ibatis。annotations。Select;MapperpublicinterfaceBookDao{Select(selectfromtblbookwhereid{id})publicBookgetById(Integerid);}packagecom。itheima。domain;publicclassBook{privateIntegerid;privateStringname;privateStringtype;privateStringdescription;OverridepublicStringtoString(){returnBook{idid,namename,typetype,descriptiondescription};}publicIntegergetId(){returnid;}publicvoidsetId(Integerid){this。idid;}publicStringgetName(){returnname;}publicvoidsetName(Stringname){this。namename;}publicStringgetType(){returntype;}publicvoidsetType(Stringtype){this。typetype;}publicStringgetDescription(){returndescription;}publicvoidsetDescription(Stringdescription){this。descriptiondescription;}}启动类packagecom。itheima。springboot8mybatis;importorg。mybatis。spring。annotation。MapperScan;importorg。springframework。boot。SpringApplication;importorg。springframework。boot。autoconfigure。SpringBootApplication;SpringBootApplicationMapperScan({com。itheima})publicclassSpringboot8MybatisApplication{publicstaticvoidmain(String〔〕args){SpringApplication。run(Springboot8MybatisApplication。class,args);}}application。ymlspring:datasource:driverclassname:com。mysql。cj。jdbc。Driverurl:jdbc:mysql:localhost:3306ssmdb?serverTimezoneUTCusername:rootpassword:caicai123type:com。alibaba。druid。pool。DruidDataSourcetestpackagecom。itheima。springboot8mybatis;importcom。itheima。dao。BookDao;importcom。itheima。domain。Book;importorg。junit。jupiter。api。Test;importorg。springframework。beans。factory。annotation。Autowired;importorg。springframework。boot。test。context。SpringBootTest;SpringBootTestclassSpringboot8MybatisApplicationTests{AutowiredprivateBookDaobookDao;TestvoidtestGetById(){BookbookbookDao。getById(1);System。out。println(book);}}pom。xmllt;?xmlversion1。0encodingUTF8?projectxmlnshttp:maven。apache。orgPOM4。0。0xmlns:xsihttp:www。w3。org2001XMLSchemainstancexsi:schemaLocationhttp:maven。apache。orgPOM4。0。0https:maven。apache。orgxsdmaven4。0。0。xsdmodelVersion4。0。0modelVersionparentgroupIdorg。springframework。bootgroupIdspringbootstarterparentartifactIdversion2。5。0versionparentgroupIdcom。itheimagroupIdspringboot08mybatisartifactIdversion0。0。1SNAPSHOTversionpropertiesjava。version1。8java。versionpropertiesdependenciesdependencygroupIdorg。mybatis。spring。bootgroupIdmybatisspringbootstarterartifactIdversion2。2。0versiondependencydependencygroupIdmysqlgroupIdmysqlconnectorjavaartifactIdscoperuntimescopedependencydependencygroupIdorg。springframework。bootgroupIdspringbootstartertestartifactIdscopetestscopedependencydependencygroupIdcom。alibabagroupIddruidartifactIdversion1。1。16versiondependencydependenciesbuildpluginsplugingroupIdorg。springframework。bootgroupIdspringbootmavenpluginartifactIdpluginpluginsbuildproject 文件结构如下