1、pom.xml添加mybatis和逆向插件依赖：

<dependency>
    <groupId>org.mybatis.spring.boot</groupId>
    <artifactId>mybatis-spring-boot-starter</artifactId>
    <version>1.3.2</version>
</dependency>

<!-- mybatis-generator-core 反向生成java代码-->
<dependency>
    <groupId>org.mybatis.generator</groupId>
    <artifactId>mybatis-generator-core</artifactId>
    <version>1.3.5</version>
</dependency>    

2、application.properties配置数据库连接信息：

#mysql数据配置
spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test?useSSL=false&useUnicode=true&characterEncoding=utf-8
spring.datasource.username=test
spring.datasource.password=test

3、写mybatis-generator.xml文件：

<?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">
<!-- mybatis逆向生成xml配置 -->
<generatorConfiguration>
    <properties resource="application.properties" /> <!-- 数据库连接配置文件 -->
    <context id="sqlserverTables" targetRuntime="MyBatis3">
        <!-- 生成的pojo，将implements Serializable-->
        <plugin type="org.mybatis.generator.plugins.SerializablePlugin"></plugin>
        <commentGenerator>
            <!-- 是否去除自动生成的注释 true：是 ： false:否 -->
            <property name="suppressAllComments" value="true" />
        </commentGenerator>

        <!-- 数据库链接URL、用户名、密码 -->
        <jdbcConnection driverClass="${spring.datasource.driverClassName}"
                        connectionURL="${spring.datasource.url}"
                        userId="${spring.datasource.username}"
                        password="${spring.datasource.password}">
        </jdbcConnection>

        <!--
            默认false，把JDBC DECIMAL 和 NUMERIC 类型解析为 Integer
            true，把JDBC DECIMAL 和 NUMERIC 类型解析为java.math.BigDecimal
        -->
        <javaTypeResolver>
            <property name="forceBigDecimals" value="false" />
        </javaTypeResolver>

        <!--
            生成model模型，对应的包路径，以及文件存放路径(targetProject)，targetProject可以指定具体的路径,如./src/main/java，
            也可以使用“MAVEN”来自动生成，这样生成的代码会在target/generatord-source目录下
        -->
        <!--<javaModelGenerator targetPackage="com.joey.mybaties.test.pojo" targetProject="MAVEN">-->
        <javaModelGenerator targetPackage="com.example.demo.entity" targetProject="./src/main/java">
            <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>

        <!--对应的mapper.xml文件  -->
        <sqlMapGenerator targetPackage="config/xml" targetProject="./src/main/resources">
            <property name="enableSubPackages" value="true"/>
        </sqlMapGenerator>

        <!-- 对应的Mapper接口类文件 -->
        <javaClientGenerator type="XMLMAPPER" targetPackage="com.example.demo.mapper" targetProject="./src/main/java">
            <property name="enableSubPackages" value="true"/>
        </javaClientGenerator>

        <!-- 列出要生成代码的所有表，这里配置的是不生成Example文件 -->
        <table tableName="user_info" domainObjectName="UserInfo"
               enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false"
               enableSelectByExample="false" selectByExampleQueryId="false" >
            <property name="useActualColumnNames" value="false"/>
        </table>
    </context>
</generatorConfiguration>

4、编写GenMain.java类：

package com.example.demo.CodeGenerator;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import org.mybatis.generator.api.MyBatisGenerator;
import org.mybatis.generator.config.Configuration;
import org.mybatis.generator.config.xml.ConfigurationParser;
import org.mybatis.generator.exception.InvalidConfigurationException;
import org.mybatis.generator.exception.XMLParserException;
import org.mybatis.generator.internal.DefaultShellCallback;
import org.springframework.util.ResourceUtils;
/**************************************
* 类说明:
*     mybatis逆向工程main函数
***************************************
*/
public class GenMain {
    public static void main(String[] args) throws FileNotFoundException {
        List<String> warnings = new ArrayList<String>();  
        boolean overwrite = true;
        //如果这里出现空指针，直接写绝对路径即可。
        String genCfg = "E:\\cloud\\demo\\src\\test\\resources\\config\\mybatis-generator.xml";
//        File configFile = new File(GenMain.class.getResource(genCfg).getFile()); //获取路径出错
        File configFile = ResourceUtils.getFile(genCfg);
        ConfigurationParser cp = new ConfigurationParser(warnings);
        Configuration config = null;  
        try {  
            config = cp.parseConfiguration(configFile);  
        } catch (IOException e) {  
            e.printStackTrace();  
        } catch (XMLParserException e) {  
            e.printStackTrace();  
        }  
        DefaultShellCallback callback = new DefaultShellCallback(overwrite);  
        MyBatisGenerator myBatisGenerator = null;  
        try {  
            myBatisGenerator = new MyBatisGenerator(config, callback, warnings);  
        } catch (InvalidConfigurationException e) {  
            e.printStackTrace();  
        }  
        try {  
            myBatisGenerator.generate(null);  
        } catch (SQLException e) {  
            e.printStackTrace();  
        } catch (IOException e) {  
            e.printStackTrace();  
        } catch (InterruptedException e) {  
            e.printStackTrace();  
        }  
    }
}

5、运行GenMain.java类的main方法，刷新项目即可。