<dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <!--https://github.com/abel533/Mapper/wiki-->
        <dependency>
            <groupId>tk.mybatis</groupId>
            <artifactId>mapper-spring-boot-starter</artifactId>
            <version>2.1.5</version>
        </dependency>

     <plugin>
                <groupId>org.mybatis.generator</groupId>
                <artifactId>mybatis-generator-maven-plugin</artifactId>
                <version>1.3.6</version>
                <configuration>
                    <configurationFile>
                        ${basedir}/src/main/resources/generator/generatorConfig.xml
                    </configurationFile>
                    <overwrite>true</overwrite>
                    <verbose>true</verbose>
                </configuration>
                <dependencies>
                    <dependency>
                        <groupId>mysql</groupId>
                        <artifactId>mysql-connector-java</artifactId>
                        <version>5.1.47</version>
                    </dependency>
                    <dependency>
                        <groupId>tk.mybatis</groupId>
                        <artifactId>mapper</artifactId>
                        <version>4.0.0</version>
                    </dependency>
                </dependencies>
            </plugin>

generator/config.properties

jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/user_center?characterEncoding=utf8&useSSL=true&nullCatalogMeansCurrent=true
jdbc.user=root
jdbc.password=123456

tableName=user
moduleName=user

generator/generatorConfig.xml

<!DOCTYPE generatorConfiguration
        PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">

<generatorConfiguration>
    <properties resource="generator/config.properties"/>

    <context id="Mysql" targetRuntime="MyBatis3Simple" defaultModelType="flat">
        <property name="beginningDelimiter" value="`"/>
        <property name="endingDelimiter" value="`"/>

        <plugin type="tk.mybatis.mapper.generator.MapperPlugin">
            <property name="mappers" value="tk.mybatis.mapper.common.Mapper"/>
            <property name="caseSensitive" value="true"/>
        </plugin>

        <jdbcConnection driverClass="${jdbc.driverClass}"
                        connectionURL="${jdbc.url}"
                        userId="${jdbc.user}"
                        password="${jdbc.password}">
        </jdbcConnection>

        <javaModelGenerator targetPackage="com.fly.demo.domain.entity.${moduleName}"
                            targetProject="src/main/java"/>

        <sqlMapGenerator targetPackage="com.fly.demo.dao.${moduleName}"
                         targetProject="src/main/resources"/>

        <javaClientGenerator targetPackage="com.fly.demo.dao.${moduleName}"
                             targetProject="src/main/java"
                             type="XMLMAPPER"/>

        <table tableName="${tableName}">
            <generatedKey column="id" sqlStatement="JDBC"/>
        </table>
    </context>
</generatorConfiguration>

使用

@MapperScan("com.fly")
@SpringBootApplication
public class DemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

}

测试

@SpringBootTest
class DemoApplicationTests {
    @Autowired
    private UserMapper userMapper;

    @Test
    void insertSelective() {
        User user = new User();
        user.setCreateTime(new Date());
        user.setUpdateTime(new Date());
        user.setAvatarUrl("xxx");
        userMapper.insertSelective(user);
        System.out.println(user);
    }

    @Test
    void select(){
        userMapper.selectAll().forEach(System.out::println);
    }
}