背景：如何使用mybatis-generator插件自动生成数据库中表的pojo类，mapper接口，mapper文件
第一步：
在src/main/resources下面创建jdbc.properties文件，内容如下：
driverClassName=com.mysql.cj.jdbc.Driver url=jdbc:mysql://ip:port/database?serverTimezone=Hongkong&useUnicode=true&characterEncoding=utf-8 username=*** password=***
第二步：
在src/main/resources下面创建generator/generatorConfig.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">
<generatorConfiguration>
<properties resource="jdbc.properties"/>
<context id="testTables" targetRuntime="MyBatis3Simple" defaultModelType="flat">
<!--注释生成器-->
<commentGenerator>
<!-- 是否去除自动生成的注释 true：是 ： false:否 -->
<!-- <property name="suppressAllComments" value="true" />-->
<property name="suppressDate" value="true"/>
</commentGenerator>
<!--数据库连接的信息：驱动类、连接地址、用户名、密码 -->
<jdbcConnection driverClass="${driverClassName}"
connectionURL="${url}" userId="${username}"
password="${password}">
</jdbcConnection>
<!-- 默认false，把JDBC DECIMAL 和 NUMERIC 类型解析为 Integer，为 true时把JDBC DECIMAL 和
NUMERIC 类型解析为java.math.BigDecimal -->
<!-- <javaTypeResolver type=""></javaTypeResolver>-->
<!-- <javaTypeResolver>-->
<!-- <property name="forceBigDecimals" value="false" />-->
<!-- </javaTypeResolver>-->
<!-- targetProject:生成PO类的位置 -->
<javaModelGenerator targetPackage="com.****.entity"
targetProject="src/main/java">
<!-- enableSubPackages:是否让schema作为包的后缀 -->
<!-- <property name="enableSubPackages" value="false" />-->
<!-- 从数据库返回的值被清理前后的空格 -->
<property name="trimStrings" value="true" />
</javaModelGenerator>
<!-- targetProject:mapper映射文件生成的位置
如果maven工程只是单独的一个工程，targetProject="src/main/java"
若果maven工程是分模块的工程，targetProject="所属模块的名称"，例如：
targetProject="ecps-manager-mapper"，下同-->
<sqlMapGenerator targetPackage="mybatis.mapper"
targetProject="src/main/resources">
<!-- enableSubPackages:是否让schema作为包的后缀 -->
<property name="enableSubPackages" value="false" />
</sqlMapGenerator>
<!-- targetPackage：mapper接口生成的位置 -->
<javaClientGenerator type="XMLMAPPER"
targetPackage="com.****.mapper"
targetProject="src/main/java">
<!-- enableSubPackages:是否让schema作为包的后缀 -->
<property name="enableSubPackages" value="false" />
</javaClientGenerator>
<table tableName="batch" domainObjectName="Batch">
<generatedKey column="id" sqlStatement="Mysql"></generatedKey>
</table>
<table tableName="batch_record" domainObjectName="BatchRecord">
<generatedKey column="id" sqlStatement="Mysql"></generatedKey>
</context>
第三步：
在pom.xml文件中增加mybatis-generator插件和mysql-connector-java依赖
<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.3.2.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.***</groupId>
<artifactId>****</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>benchmark</name>
<description>benchmark</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>2.1.3</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.26</version>
<!-- <scope>runtime</scope>-->
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-configuration-processor</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>
<!--custom-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.12</version>
</dependency>
<dependency>
<groupId>redis.clients</groupId>
<artifactId>jedis</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.75</version>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-text</artifactId>
<version>1.6</version>
</dependency>
<dependency>
<groupId>com.arronlong</groupId>
<artifactId>httpclientutil</artifactId>
<version>1.0.4</version>
</dependency>
<dependency>
<groupId>io.esastack</groupId>
<artifactId>httpclient-core</artifactId>
<version>0.1.0</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.10</version>
</dependency>
<dependency>
<groupId>jakarta.validation</groupId>
<artifactId>jakarta.validation-api</artifactId>
<version>2.0.2</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-validation</artifactId>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-assembly-plugin</artifactId>
<version>2.6</version>
<configuration>
<descriptor>src/main/assembly/assembly.xml</descriptor>
</configuration>
<executions>
<execution>
<id>make-assembly</id>
<phase>package</phase>
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>${java.version}</source>
<target>${java.version}</target>
<encoding>UTF-8</encoding>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-source-plugin</artifactId>
<version>3.2.1</version>
<configuration>
<attach>true</attach>
</configuration>
<executions>
<execution>
<phase>compile</phase>
<goals>
<goal>jar</goal>
</goals>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>${spring-boot.version}</version>
</plugin>
<plugin>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-maven-plugin</artifactId>
<version>1.3.2</version>
<configuration>
<configurationFile>src/main/resources/generator/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>1.3.2</version>
</dependency>
<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.26</version>
</dependency>
</dependencies>
</plugin>
</plugins>
</build>
</project>
第四步：
点击maven刷新按钮，下载相关依赖和安装相关插件
第五步：
双击plugins插件列表里面的mybatis-generator:generate生成pojo类，mapper接口，mapper文件
关于mybatis-generator配置文件的更详细的讲解参考：https://liuzh.blog.csdn.net/article/details/42102297