注意以下5点配置：

image.png

Gradle配置文件参考：

plugins {
    id'org.springframework.boot' version'2.1.6.RELEASE'
    id'java'
    //gradle提供的mybatis generator插件
    id"com.arenagod.gradle.MybatisGenerator" version"1.4"
}

applyplugin:'io.spring.dependency-management'
//引入 mybatis-generator 插件
applyplugin:"com.arenagod.gradle.MybatisGenerator"

group ='com.XXXX.base.auth'

version ='0.0.1-SNAPSHOT'
sourceCompatibility ='1.8'
configurations {

developmentOnly
    runtimeClasspath {
    extendsFromdevelopmentOnly
    }
// remove default logger
    all*.excludegroup:'org.springframework.boot',module:'spring-boot-starter-logging'
    // 引入mybatisGenerator插件
    mybatisGenerator
}

repositories {
// 使用阿里云的MAVEN仓库地址
    maven {
        url'http://maven.aliyun.com/nexus/content/groups/public/'
    }
    mavenCentral()
}

dependencies {
    implementation'org.springframework.boot:spring-boot-starter-freemarker'
    implementation'org.springframework.boot:spring-boot-starter-oauth2-resource-server'
    implementation'org.springframework.boot:spring-boot-starter-security'
    implementation'org.springframework.boot:spring-boot-starter-web'
    implementation'org.mybatis.spring.boot:mybatis-spring-boot-starter:2.1.0'
    developmentOnly'org.springframework.boot:spring-boot-devtools'
    implementation'org.springframework.boot:spring-boot-starter-aop'
    implementation'org.springframework.boot:spring-boot-starter-data-redis'
    implementation'org.springframework.boot:spring-boot-starter-log4j2'
    runtimeOnly'mysql:mysql-connector-java'
    testImplementation'org.springframework.boot:spring-boot-starter-test'
    testImplementation'org.springframework.security:spring-security-test'
    testImplementation'org.mybatis.generator:mybatis-generator-core:1.3.2'
    // ………………此处省略N个配置………………
}

// mybatis-generator.xml 配置路径
//这里会遇到个问题：MyBatis Generator 通过xml生成，有日志但是没有生成文件成功的问题，
//原因：mac下是找不到 ./src 路径的，需要全路径，如下配置。windows则为src/main/resources/generator.xml
mybatisGenerator {
    verbose =true
    configFile ='src/main/resources/conf/generator.xml'
}

generator.xml参考

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE generatorConfiguration
        PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">
<generatorConfiguration>
    <context id="my" targetRuntime="MyBatis3">

        <!--自动实现Serializable接口-->
        <plugin type="org.mybatis.generator.plugins.SerializablePlugin"></plugin>

        <!-- 去除自动生成的注释 -->
        <commentGenerator>
            <property name="suppressAllComments" value="true" />
        </commentGenerator>

        <!--数据库基本信息-->
        <jdbcConnection driverClass="com.mysql.jdbc.Driver"
                        connectionURL="jdbc:mysql://127.0.0.1:3306/XXXX"
                        userId="root"
                        password="admin">
        </jdbcConnection>

        <!--生成实体类的位置以及包的名字-->
        <!--同样Mac用户：targetProject 为全路径（/Users/murasakiseifu/mybatisGenerator/src/main/java）-->
        <javaModelGenerator targetPackage="com.XXXX.base.auth.entity" targetProject="src/main/java">
            <!-- enableSubPackages:是否让schema作为包的后缀 -->
            <property name="enableSubPackages" value="true" />
            <!-- 从数据库返回的值被清理前后的空格 -->
            <property name="trimStrings" value="true" />
        </javaModelGenerator>

        <!--生成映射文件存放位置-->
        <!--同样Mac用户：targetProject 为全路径（/Users/murasakiseifu/mybatisGenerator/src/main/resources"）-->
        <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources">
            <!-- enableSubPackages:是否让schema作为包的后缀 -->
            <property name="enableSubPackages" value="false"/>
        </sqlMapGenerator>

        <!--生成Dao类存放位置,mapper接口生成的位置-->
        <!--同样Mac用户：targetProject 为全路径（/Users/murasakiseifu/mybatisGenerator/src/main/java）-->
        <javaClientGenerator type="XMLMAPPER" targetPackage="com.XXXX.base.auth.dao" targetProject="src/main/java">
            <!-- enableSubPackages:是否让schema作为包的后缀 -->
            <property name="enableSubPackages" value="false"/>
        </javaClientGenerator>

        <!-- 配置表信息 -->
        <!-- schema即为数据库名 tableName为对应的数据库表 domainObjectName是要生成的实体类 enable*ByExample 是否生成 example类 -->
        <table schema="hisp" tableName="human_users"
               domainObjectName="human_users" enableCountByExample="false"
               enableDeleteByExample="false" enableSelectByExample="false"
               enableUpdateByExample="false">
        </table>

    </context>
</generatorConfiguration>

刷新Gradle后可以双击mbGenerator运行（前提是要配置好自己的generator.xml哦）

image.png

参考，感谢：
MurasakiSeiFu
https://segmentfault.com/a/1190000013534059