新建maven工程

在resources目录下新建配置文件generatorConfig.xml

<?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>
    <!--配置要链接的数据库的数据源-->
    <classPathEntry location="D:/maven_repository/mysql/mysql-connector-java/8.0.26/mysql-connector-java-8.0.26.jar"/>
    <!---Mybatis上下文-->
    <context id="MySqlContext" targetRuntime="MyBatis3">
        <!--配置数据库的链接信息-->
        <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
                        connectionURL="jdbc:mysql://localhost:3306/test?useUnicode=true&amp;characterEncoding=UTF-8"
                        userId="root"
                        password="root"/>
        <!--数据库BigDecimals字段在java中定义-->
        <javaTypeResolver>
            <property name="forceBigDecimals" value="true"/>
        </javaTypeResolver>
        <!--实体类生成信息-->
        <javaModelGenerator targetPackage="com.simon.app.entity" targetProject="./src/main/java">
            <property name="enableSubPackages" value="true"/>
            <property name="trimStrings" value="true"/>
        </javaModelGenerator>
        <!--mybatis 的xml文件地址-->
        <sqlMapGenerator targetPackage="com.simon.app.repository" targetProject="./src/main/java">
            <property name="enableSubPackages" value="true"/>
        </sqlMapGenerator>
        <!--mybatis的mapper接口-->
        <javaClientGenerator targetPackage="com.simon.app.repository" targetProject="src/main/java" type="XMLMAPPER">
            <property name="enableSubPackages" value="true"/>
        </javaClientGenerator>
        <!--要生成的表结构-->
        <table tableName="t_account" domainObjectName="Account"
               enableCountByExample="false" enableUpdateByExample="false"
               enableDeleteByExample="false" enableSelectByExample="false"
               selectByExampleQueryId="false">
        </table>

    </context>

</generatorConfiguration>

pom.xml新增如下内容

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.simon</groupId>
    <artifactId>app</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <simon.version>1.0.0</simon.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>

        <mybatis.version>3.5.7</mybatis.version>
        <mybatis_generator.version>1.4.0</mybatis_generator.version>
        <mysql-jdbc.verison>8.0.26</mysql-jdbc.verison>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>${mybatis.version}</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>${mysql-jdbc.verison}</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis.generator</groupId>
            <artifactId>mybatis-generator-core</artifactId>
            <version>${mybatis_generator.version}</version>
        </dependency>
    </dependencies>

   <build>
       <plugins>
           <plugin>
               <groupId>org.mybatis.generator</groupId>
               <artifactId>mybatis-generator-maven-plugin</artifactId>
               <version>1.4.0</version>
               <configuration>
                   <configurationFile>src/main/resources/generatorConfig.xml</configurationFile>
                   <verbose>true</verbose>
                   <overwrite>true</overwrite>
               </configuration>
               <executions>
                   <execution>
                       <id>Generate MyBatis Artifacts</id>
                       <goals>
                           <goal>generate</goal>
                       </goals>
                   </execution>
               </executions>
               <dependencies>
                   <dependency>
                       <groupId>org.mybatis.generator</groupId>
                       <artifactId>mybatis-generator-core</artifactId>
                       <version>1.4.0</version>
                   </dependency>
               </dependencies>
           </plugin>
       </plugins>
   </build>
</project>

执行mvn命令：mvn mybatis-generator:generate

注意：在执行前应将maven加入环境变量