修改启动类，增加@MapperScan("com.example.mybatistest.dao"),以自动扫描dao目录，避免每个dao都手动加@Mapper注解。代码如下：
@SpringBootApplication @MapperScan("com.example.mybatistest.dao") public class MybatisTestApplication { public static void main(String[] args) { SpringApplication.run(MybatisTestApplication.class, args); } } 修改application.yml,配置项目，代码如下： mybatis: #对应实体类路径 type-aliases-package: com.example.mybatistest.entity #对应mapper映射文件路径 mapper-locations: classpath:mapper/*.xml #pagehelper物理分页配置 pagehelper: helper-dialect: mysql reasonable: true support-methods-arguments: true params: count=countSql returnPageInfo: check server: port: 8081 spring: datasource: name: mysqlTest type: com.alibaba.druid.pool.DruidDataSource #druid连接池相关配置 druid: #监控拦截统计的filters filters: stat driver-class-name: com.mysql.jdbc.Driver url: jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf-8&useSSL=true username: root password: 123456 #配置初始化大小，最小，最大 initial-size: 1 min-idle: 1 max-active: 20 #获取连接等待超时时间 max-wait: 6000 #间隔多久检测一次需要关闭的空闲连接 time-between-eviction-runs-millis: 60000 #一个连接在池中的最小生存时间 min-evictable-idle-time-millis: 300000 #打开PSCache，并指定每个连接上PSCache的大小。oracle设置为true，mysql设置为false。分库分表设置较多推荐设置 pool-prepared-statements: false max-pool-prepared-statement-per-connection-size: 20 http: encoding: charset: utf-8 enabled: true 2.编写代码