SpringBoot入门

　　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