添加 maven 依赖

<!-- mybatis plus 代码生成器 start --> <dependency> <groupId>com.baomidou</groupId> <artifactId>mybatis-plus-generator</artifactId> <version>3.5.3.1</version> </dependency> <dependency> <groupId>org.apache.velocity</groupId> <artifactId>velocity-engine-core</artifactId> <version>2.0</version> <scope>compile</scope> </dependency> <!-- <dependency> <groupId>io.springfox</groupId> <artifactId>springfox-boot-starter</artifactId> <version>3.0.0</version> </dependency> --> <!-- mybatis plus 代码生成器 end -->