src/main/java/
  └── com/example/entity/
      ├── User.java              ← 实体类（POJO）
      └── UserExample.java       ← 查询条件类（QBC风格）
  └── com/example/mapper/
      └── UserMapper.java        ← Mapper 接口
src/main/resources/
  └── mapper/
      └── UserMapper.xml         ← SQL 映射文件

 src/main/java/
   └── com/example/
       ├── entity/User.java       ← 实体类（含 Lombok / Swagger 注解）
       ├── mapper/UserMapper.java ← Mapper 接口（继承 BaseMapper）
       ├── service/
       │   ├── UserService.java       ← Service 接口
       │   └── impl/UserServiceImpl.java ← Service 实现
       └── controller/UserController.java ← Controller
 src/main/resources/
  └── mapper/
      └── UserMapper.xml         ← SQL 映射文件（可选）

 ┌──────────────────────────────────────────────────┐
 │              MyBatis Generator                    │
 │                                                    │
 │  ┌──────────┐   ┌───────────┐   ┌──────────────┐ │
 │  │ Database  │   │ Generator  │   │  Generated   │ │
 │  │  Metadata │──→│   Engine   │──→│    Code      │ │
 │  │ (JDBC)    │   │ (Java)     │   │  (Java/XML)  │ │
 │  └──────────┘   └─────┬─────┘   └──────────────┘ │
 │                       │                            │
│              ┌────────┴────────┐                   │
│              │  Configuration  │                   │
│              │  (XML / Java)   │                   │
│              └─────────────────┘                   │
└──────────────────────────────────────────────────┘

 mybatis-generator-demo/
 ├── pom.xml
 ├── src/
 │   ├── main/
 │   │   ├── java/
 │   │   │   └── com/example/
 │   │   │       ├── entity/
 │   │   │       ├── mapper/
 │   │   │       └── generator/
│   │   │           └── Generator.java
│   │   └── resources/
│   │       ├── generatorConfig.xml
│   │       └── mapper/
│   └── test/
└── lib/
    └── mysql-connector-j-8.0.33.jar

 <?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>com.example</groupId>
     <artifactId>mybatis-generator-demo</artifactId>
    <version>1.0.0</version>
    <packaging>jar</packaging>
    <properties>
        <maven.compiler.source>17</maven.compiler.source>
        <maven.compiler.target>17</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
    <dependencies>
        <!-- MyBatis -->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.16</version>
        </dependency>
        <!-- MySQL 驱动 -->
        <dependency>
            <groupId>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
            <version>8.0.33</version>
        </dependency>
        <!-- MyBatis Generator 核心 -->
        <dependency>
            <groupId>org.mybatis.generator</groupId>
            <artifactId>mybatis-generator-core</artifactId>
            <version>1.4.2</version>
        </dependency>
        <!-- Log4j2（可选，用于日志输出） -->
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>2.22.1</version>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <!-- MyBatis Generator Maven 插件 -->
            <plugin>
                <groupId>org.mybatis.generator</groupId>
                <artifactId>mybatis-generator-maven-plugin</artifactId>
                <version>1.4.2</version>
                <configuration>
                    <!-- 配置文件路径 -->
                    <configurationFile>
                        src/main/resources/generatorConfig.xml
                    </configurationFile>
                    <!-- 是否覆盖已有文件 -->
                    <overwrite>true</overwrite>
                    <!-- 是否将 MBG 的输出打印到控制台 -->
                    <verbose>true</verbose>
                </configuration>
                <dependencies>
                    <!-- MySQL 驱动（插件也需要） -->
                    <dependency>
                        <groupId>com.mysql</groupId>
                        <artifactId>mysql-connector-j</artifactId>
                        <version>8.0.33</version>
                    </dependency>
                </dependencies>
            </plugin>
        </plugins>
    </build>
</project>

 -- 创建数据库
 CREATE DATABASE IF NOT EXISTS mybatis_demo DEFAULT CHARSET utf8mb4;
 USE mybatis_demo;
 -- 部门表
 CREATE TABLE dept (
     dept_id    INT PRIMARY KEY AUTO_INCREMENT COMMENT '部门ID',
     dept_name  VARCHAR(50) NOT NULL COMMENT '部门名称',
     location   VARCHAR(100) COMMENT '部门位置'
) COMMENT '部门表';
-- 员工表
CREATE TABLE emp (
    emp_id      INT PRIMARY KEY AUTO_INCREMENT COMMENT '员工ID',
    emp_name    VARCHAR(50) NOT NULL COMMENT '员工姓名',
    gender      CHAR(1) DEFAULT 'M' COMMENT '性别 M-男 F-女',
    email       VARCHAR(100) COMMENT '邮箱',
    salary      DECIMAL(10,2) COMMENT '工资',
    dept_id     INT COMMENT '所属部门ID',
    hire_date   DATE COMMENT '入职日期',
    create_time DATETIME DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
    update_time DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT
     '更新时间',
    FOREIGN KEY (dept_id) REFERENCES dept(dept_id)
) COMMENT '员工表';
-- 插入测试数据
INSERT INTO dept VALUES (1, '研发部', '北京'), (2, '市场部', '上海'), (3, '财务部', '广州');
INSERT INTO emp VALUES
(1, '张三', 'M', 'zhangsan@qq.com', 15000.00, 1, '2020-01-15', NOW(), NOW()),
(2, '李四', 'F', 'lisi@qq.com', 12000.00, 2, '2021-03-20', NOW(), NOW()),
(3, '王五', 'M', 'wangwu@qq.com', 18000.00, 1, '2019-07-01', NOW(), NOW());

 package com.example.generator;
 import org.mybatis.generator.api.MyBatisGenerator;
 import org.mybatis.generator.config.xml.ConfigurationParser;
 import org.mybatis.generator.config.Configuration;
 import org.mybatis.generator.internal.DefaultShellCallback;
 import java.io.File;
 import java.util.ArrayList;
import java.util.List;
public class Generator {
    public static void main(String[] args) throws Exception {
        List<String> warnings = new ArrayList<>();
        boolean overwrite = true;  // 是否覆盖已有文件
        // 指向配置文件
        File configFile = new File("src/main/resources/generatorConfig.xml");
        ConfigurationParser parser = new ConfigurationParser(warnings);
        Configuration config = parser.parseConfiguration(configFile);
        DefaultShellCallback callback = new DefaultShellCallback(overwrite);
        MyBatisGenerator generator = new MyBatisGenerator(config, callback, warnings);
        // 执行生成
        generator.generate(null);
        // 打印警告信息
        for (String warning : warnings) {
            System.out.println(warning);
        }
        System.out.println("✅ 代码生成完成！");
    }
}

# 1. 准备 mybatis-generator-core 和数据库驱动
# 2. 准备 generatorConfig.xml
# 3. 执行生成命令
java -jar mybatis-generator-core-1.4.2.jar -configfile generatorConfig.xml -overwrite

# 常用参数：
# -configfile 指定配置文件路径
# -overwrite 允许覆盖可覆盖的 Java 文件
# -verbose 输出详细信息

 <?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>
     <!-- ① 引入外部属性文件 -->
     <properties resource="generator.properties"/>
    <!-- ② classPathEntry：指定数据库驱动路径（Maven插件方式可省略） -->
    <classPathEntry location="lib/mysql-connector-j-8.0.33.jar"/>
    <!-- ③ context：生成上下文（可配置多个） -->
    <context id="mysqlContext" targetRuntime="MyBatis3"
     defaultModelType="conditional">
        <!-- ====== 内置插件配置 ====== -->
        <!-- ④ 序列化插件（让实体类实现 Serializable） -->
        <plugin type="org.mybatis.generator.plugins.SerializablePlugin"/>
        <!-- ⑤ ToString 插件（生成 toString 方法） -->
        <plugin type="org.mybatis.generator.plugins.ToStringPlugin"/>
        <!-- ⑥ EqualsAndHashCode 插件 -->
        <plugin type="org.mybatis.generator.plugins.EqualsAndHashCodePlugin"/>
        <!-- ⑦ Row Bounds 插件（分页用，MySQL 不推荐） -->
        <!-- <plugin type="org.mybatis.generator.plugins.RowBoundsPlugin"/> -->
        <!-- ⑧ 虚拟主键插件 -->
        <!-- <plugin type="org.mybatis.generator.plugins.VirtualKeyPlugin"/> -->
        <!-- ====== 注释生成器 ====== -->
        <!-- ⑨ 自定义注释生成器 -->
        <commentGenerator>
            <!-- 是否去除自动生成的注释 true：去除 false：保留 -->
            <property name="suppressAllComments" value="false"/>
            <!-- 是否生成注释中的日期 -->
            <property name="suppressDate" value="true"/>
            <!-- 是否添加数据库表的字段备注 -->
            <property name="addRemarkComments" value="true"/>
        </commentGenerator>
        <!-- ====== 数据库连接 ====== -->
        <!-- ⑩ JDBC 连接配置 -->
         <jdbcConnection
             driverClass="${jdbc.driver}"
             connectionURL="${jdbc.url}"
             userId="${jdbc.username}"
             password="${jdbc.password}">
             <!-- MySQL 8.x 需要设置以下属性，才能获取表注释 -->
             <property name="useInformationSchema" value="true"/>
         </jdbcConnection>
         <!-- ====== 类型解析 ====== -->
         <!-- ⑪ Java 类型解析器 -->
         <javaTypeResolver>
             <!-- 是否强制使用 BigDecimal -->
             <property name="forceBigDecimals" value="false"/>
             <!-- 是否使用 JSR-310 日期类型（java.time） -->
             <property name="useJSR310Types" value="true"/>
         </javaTypeResolver>
         <!-- ====== 代码生成器 ====== -->
         <!-- ⑫ Java 实体类生成器 -->
         <javaModelGenerator
             targetPackage="com.example.entity"
             targetProject="src/main/java">
             <!-- 是否让 schema 作为包的后缀 -->
             <property name="enableSubPackages" value="false"/>
             <!-- 从数据库返回的值是否清理前后的空格 -->
             <property name="trimStrings" value="true"/>
             <!-- 是否为实体类生成构造方法 -->
             <property name="constructorBased" value="false"/>
             <!-- 是否不可变（final 类，全参构造，无 setter） -->
             <property name="immutable" value="false"/>
             <!-- 父类（所有实体类继承的基类） -->
             <!-- <property name="rootClass" value="com.example.BaseEntity"/> -->
         </javaModelGenerator>
         <!-- ⑬ SQL 映射文件生成器 -->
         <sqlMapGenerator
             targetPackage="mapper"
             targetProject="src/main/resources">
             <property name="enableSubPackages" value="false"/>
         </sqlMapGenerator>
         <!-- ⑭ Mapper 接口生成器 -->
         <javaClientGenerator
             type="XMLMAPPER"
             targetPackage="com.example.mapper"
             targetProject="src/main/java">
             <property name="enableSubPackages" value="false"/>
             <!-- 父接口（所有 Mapper 继承的接口） -->
             <!-- <property name="rootInterface" value="com.example.BaseMapper"/> -->
        </javaClientGenerator>
        <!-- ====== 表配置 ====== -->
        <!-- ⑮ table：每张表配置一个 -->
        <table schema="mybatis_demo" tableName="emp"
               domainObjectName="Emp"
               enableCountByExample="true"
               enableDeleteByExample="true"
               enableSelectByExample="true"
               enableUpdateByExample="true"
               enableDeleteByPrimaryKey="true"
               enableInsert="true"
               enableSelectByPrimaryKey="true"
               enableUpdateByPrimaryKey="true">
            <!-- 主键策略：将自增主键回填到实体 -->
            <generatedKey column="emp_id" sqlStatement="MySql" identity="true"/>
            <!-- 列覆盖：强制指定某列的 Java 类型 -->
            <!-- <columnOverride column="salary" property="salary"
      javaType="java.math.BigDecimal"/> -->
            <!-- 列忽略：不生成该字段 -->
            <!-- <ignoreColumn column="create_time"/> -->
        </table>
        <table schema="mybatis_demo" tableName="dept"
               domainObjectName="Dept"
               enableCountByExample="true"
               enableDeleteByExample="true"
               enableSelectByExample="true"
               enableUpdateByExample="true">
            <generatedKey column="dept_id" sqlStatement="MySql" identity="true"/>
        </table>
    </context>
</generatorConfiguration>

 insert()
 deleteByPrimaryKey()
 updateByPrimaryKey()
 selectByPrimaryKey()
 selectAll() (Simple 没有)
 countByExample()
 deleteByExample()
 selectByExample()
 updateByExampleSelective()
updateByExample()

 <jdbcConnection
     driverClass="com.mysql.cj.jdbc.Driver"
     connectionURL="jdbc:mysql://localhost:3306/mybatis_demo"
     userId="root"
     password="123456">
     <!-- ★ 关键：使用 information_schema 获取表/字段注释 -->
     <property name="useInformationSchema" value="true"/>
    <!-- 其他可选属性 -->
    <property name="nullCatalogMeansCurrent" value="true"/>
    <property name="characterEncoding" value="utf-8"/>
    <property name="serverTimezone" value="Asia/Shanghai"/>
</jdbcConnection>

 <!-- MySQL 8.x -->
 <jdbcConnection
     driverClass="com.mysql.cj.jdbc.Driver"
     connectionURL="jdbc:mysql://localhost:3306/mybatis_demo?
     useSSL=false&amp;serverTimezone=Asia/Shanghai"
     userId="root" password="123456">
     <property name="useInformationSchema" value="true"/>
 </jdbcConnection>
 <!-- PostgreSQL -->
<jdbcConnection
    driverClass="org.postgresql.Driver"
    connectionURL="jdbc:postgresql://localhost:5432/mydb"
    userId="postgres" password="123456"/>
<!-- Oracle -->
<jdbcConnection
    driverClass="oracle.jdbc.OracleDriver"
    connectionURL="jdbc:oracle:thin:@localhost:1521:orcl"
    userId="scott" password="tiger"/>
<!-- SQL Server -->
<jdbcConnection
    driverClass="com.microsoft.sqlserver.jdbc.SQLServerDriver"
    connectionURL="jdbc:sqlserver://localhost:1433;databaseName=mydb"
    userId="sa" password="123456"/>

 <javaModelGenerator
     targetPackage="com.example.entity"
     targetProject="src/main/java">
     <!-- 是否让 schema 作为包名后缀 -->
     <!-- true: com.example.entity.mybatis_demo.Emp -->
     <!-- false: com.example.entity.Emp -->
     <property name="enableSubPackages" value="false"/>
    <!-- 是否清理从数据库返回的字符串前后的空格 -->
    <property name="trimStrings" value="true"/>
    <!-- 是否基于构造方法（生成全参构造 + setter） -->
    <property name="constructorBased" value="false"/>
    <!-- 是否生成不可变类（final + 全参构造 + 无 setter） -->
    <property name="immutable" value="false"/>
    <!-- 所有实体类的父类 -->
    <!-- <property name="rootClass" value="com.example.BaseEntity"/> -->
</javaModelGenerator>

 package com.example.entity;
 import java.math.BigDecimal;
 import java.time.LocalDate;
 import java.time.LocalDateTime;
 public class Emp {
     private Integer empId;
    private String empName;
    private String gender;
    private String email;
    private BigDecimal salary;
    private Integer deptId;
    private LocalDate hireDate;
    private LocalDateTime createTime;
    private LocalDateTime updateTime;
    // ====== 构造方法 ======
    public Emp(Integer empId, String empName, String gender, String email,
               BigDecimal salary, Integer deptId, LocalDate hireDate,
               LocalDateTime createTime, LocalDateTime updateTime) {
        this.empId = empId;
        this.empName = empName == null ? null : empName.trim();
        this.gender = gender;
        this.email = email == null ? null : email.trim();
        this.salary = salary;
        this.deptId = deptId;
        this.hireDate = hireDate;
        this.createTime = createTime;
        this.updateTime = updateTime;
    }
    public Emp() {
    }
    // ====== getter / setter ======
    public Integer getEmpId() {
        return empId;
    }
    public void setEmpId(Integer empId) {
        this.empId = empId;
    }
    public String getEmpName() {
        return empName;
    }
    public void setEmpName(String empName) {
        this.empName = empName == null ? null : empName.trim();
    }
    // ... 其他 getter/setter 省略 ...
}

// BaseEntity.java — 所有实体类的父类
package com.example.entity;
import java.time.LocalDateTime;
public abstract class BaseEntity {
    private LocalDateTime createTime;
    private LocalDateTime updateTime;
    // getter / setter
    public LocalDateTime getCreateTime() { return createTime; }
    public void setCreateTime(LocalDateTime createTime) { this.createTime = createTime;
     }
    public LocalDateTime getUpdateTime() { return updateTime; }
    public void setUpdateTime(LocalDateTime updateTime) { this.updateTime = updateTime;
     }
}

 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
         "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
 <mapper namespace="com.example.mapper.EmpMapper">
     <resultMap id="BaseResultMap" type="com.example.entity.Emp">
         <id column="emp_id" property="empId" jdbcType="INTEGER"/>
         <result column="emp_name" property="empName" jdbcType="VARCHAR"/>
         <result column="gender" property="gender" jdbcType="CHAR"/>
        <result column="email" property="email" jdbcType="VARCHAR"/>
        <result column="salary" property="salary" jdbcType="DECIMAL"/>
        <result column="dept_id" property="deptId" jdbcType="INTEGER"/>
        <result column="hire_date" property="hireDate" jdbcType="DATE"/>
        <result column="create_time" property="createTime" jdbcType="TIMESTAMP"/>
        <result column="update_time" property="updateTime" jdbcType="TIMESTAMP"/>
    </resultMap>
    <!-- 通用列名 -->
    <sql id="Base_Column_List">
        emp_id, emp_name, gender, email, salary, dept_id, hire_date, create_time,
        update_time
    </sql>
    <!-- 按主键查询 -->
    <select id="selectByPrimaryKey" parameterType="java.lang.Integer"
            resultMap="BaseResultMap">
        SELECT
        <include refid="Base_Column_List"/>
        FROM emp
        WHERE emp_id = #{empId,jdbcType=INTEGER}
    </select>
    <!-- 删除 -->
    <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer">
        DELETE FROM emp
        WHERE emp_id = #{empId,jdbcType=INTEGER}
    </delete>
    <!-- 插入 -->
    <insert id="insert" parameterType="com.example.entity.Emp"
            useGeneratedKeys="true" keyProperty="empId">
        INSERT INTO emp (emp_name, gender, email,
                         salary, dept_id, hire_date,
                         create_time, update_time)
        VALUES (#{empName,jdbcType=VARCHAR}, #{gender,jdbcType=CHAR},
                #{email,jdbcType=VARCHAR}, #{salary,jdbcType=DECIMAL},
                #{deptId,jdbcType=INTEGER}, #{hireDate,jdbcType=DATE},
                #{createTime,jdbcType=TIMESTAMP}, #{updateTime,jdbcType=TIMESTAMP})
    </insert>
    <!-- 选择性插入（null 字段不插入） -->
    <insert id="insertSelective" parameterType="com.example.entity.Emp"
            useGeneratedKeys="true" keyProperty="empId">
        INSERT INTO emp
        <trim prefix="(" suffix=")" suffixOverrides=",">
            <if test="empName != null">emp_name,</if>
            <if test="gender != null">gender,</if>
            <if test="email != null">email,</if>
            <if test="salary != null">salary,</if>
            <if test="deptId != null">dept_id,</if>
            <if test="hireDate != null">hire_date,</if>
            <if test="createTime != null">create_time,</if>
            <if test="updateTime != null">update_time,</if>
        </trim>
        <trim prefix="VALUES (" suffix=")" suffixOverrides=",">
            <if test="empName != null">#{empName,jdbcType=VARCHAR},</if>
            <if test="gender != null">#{gender,jdbcType=CHAR},</if>
            <if test="email != null">#{email,jdbcType=VARCHAR},</if>
            <if test="salary != null">#{salary,jdbcType=DECIMAL},</if>
            <if test="deptId != null">#{deptId,jdbcType=INTEGER},</if>
            <if test="hireDate != null">#{hireDate,jdbcType=DATE},</if>
            <if test="createTime != null">#{createTime,jdbcType=TIMESTAMP},</if>
            <if test="updateTime != null">#{updateTime,jdbcType=TIMESTAMP},</if>
        </trim>
    </insert>
    <!-- 选择性更新 -->
     <update id="updateByPrimaryKeySelective" parameterType="com.example.entity.Emp">
         UPDATE emp
         <set>
             <if test="empName != null">emp_name = #{empName,jdbcType=VARCHAR},</if>
             <if test="gender != null">gender = #{gender,jdbcType=CHAR},</if>
             <if test="email != null">email = #{email,jdbcType=VARCHAR},</if>
             <if test="salary != null">salary = #{salary,jdbcType=DECIMAL},</if>
             <if test="deptId != null">dept_id = #{deptId,jdbcType=INTEGER},</if>
             <if test="hireDate != null">hire_date = #{hireDate,jdbcType=DATE},</if>
             <if test="createTime != null">create_time = #
      {createTime,jdbcType=TIMESTAMP},</if>
             <if test="updateTime != null">update_time = #
      {updateTime,jdbcType=TIMESTAMP},</if>
         </set>
         WHERE emp_id = #{empId,jdbcType=INTEGER}
     </update>
     <!-- 全量更新 -->
     <update id="updateByPrimaryKey" parameterType="com.example.entity.Emp">
         UPDATE emp
         SET emp_name    = #{empName,jdbcType=VARCHAR},
             gender      = #{gender,jdbcType=CHAR},
             email       = #{email,jdbcType=VARCHAR},
             salary      = #{salary,jdbcType=DECIMAL},
            dept_id     = #{deptId,jdbcType=INTEGER},
            hire_date   = #{hireDate,jdbcType=DATE},
            create_time = #{createTime,jdbcType=TIMESTAMP},
            update_time = #{updateTime,jdbcType=TIMESTAMP}
        WHERE emp_id = #{empId,jdbcType=INTEGER}
    </update>
</mapper>

 package com.example.mapper;
 import com.example.entity.Emp;
 import com.example.entity.EmpExample;
 import java.util.List;
 import org.apache.ibatis.annotations.Param;
 public interface EmpMapper {
    // ====== 按 Example 查询 ======
    long countByExample(EmpExample example);
    int deleteByExample(EmpExample example);
    List<Emp> selectByExample(EmpExample example);
    int updateByExampleSelective(@Param("record") Emp record,
                                  @Param("example") EmpExample example);
    int updateByExample(@Param("record") Emp record,
                         @Param("example") EmpExample example);
    // ====== 按主键操作 ======
    int deleteByPrimaryKey(Integer empId);
    int insert(Emp record);
    int insertSelective(Emp record);
    Emp selectByPrimaryKey(Integer empId);
    int updateByPrimaryKeySelective(Emp record);
    int updateByPrimaryKey(Emp record);
}

// 纯注解，没有 XML 文件
public interface EmpMapper {
    @Insert({
        "INSERT INTO emp (emp_name, gender, ...)",
        "VALUES (#{empName,jdbcType=VARCHAR}, #{gender,jdbcType=CHAR}, ...)"
    })
     @Options(useGeneratedKeys = true, keyProperty = "empId")
     int insert(Emp record);
    @Select({
        "SELECT emp_id, emp_name, gender, ...",
        "FROM emp",
        "WHERE emp_id = #{empId,jdbcType=INTEGER}"
    })
    @ResultMap("BaseResultMap")
    Emp selectByPrimaryKey(Integer empId);
    // ... 其他方法
}

 <table
     schema="mybatis_demo"           <!-- 数据库名/schema -->
     tableName="emp"                  <!-- 数据库表名（支持通配符 %） -->
     domainObjectName="Emp"           <!-- 生成的实体类名 -->
     mapperName="EmpMapper"           <!-- 生成的 Mapper 接口名（可含包名） -->
     sqlMapName="EmpMapper"           <!-- 生成的 XML 文件名 -->
     alias="e"                        <!-- 表别名（用于多表查询） -->
     enableCountByExample="true"      <!-- 是否生成 countByExample -->
     enableDeleteByExample="true"     <!-- 是否生成 deleteByExample -->
    enableSelectByExample="true"     <!-- 是否生成 selectByExample -->
    enableUpdateByExample="true"     <!-- 是否生成 updateByExample -->
    enableDeleteByPrimaryKey="true"  <!-- 是否生成 deleteByPrimaryKey -->
    enableInsert="true"              <!-- 是否生成 insert -->
    enableSelectByPrimaryKey="true"  <!-- 是否生成 selectByPrimaryKey -->
    enableUpdateByPrimaryKey="true"  <!-- 是否生成 updateByPrimaryKey -->
    selectByPrimaryKeyQueryId="false"
    selectByExampleQueryId="false"
    modelType="conditional"          <!-- 覆盖 context 的 defaultModelType -->
    delimitIdentifiers="false"       <!-- 是否给所有标识符加分隔符 -->
    delimitAllColumns="false"        <!-- 是否给所有列加分隔符 -->
>

 <table tableName="emp" domainObjectName="Emp">
     <!-- 方式一：MySQL 自增主键 -->
     <generatedKey column="emp_id" sqlStatement="MySql" identity="true"/>
     <!-- 方式二：SQL Server 自增主键 -->
     <!-- <generatedKey column="id" sqlStatement="SQL Server" identity="true"/> -->
     <!-- 方式三：Oracle 序列 -->
     <!-- <generatedKey column="id" sqlStatement="select SEQ_EMP.nextval from dual"
     identity="false"/> -->
    <!-- 方式四：PostgreSQL -->
    <!-- <generatedKey column="id" sqlStatement="PostgreSQL" identity="true"/> -->
</table>

<table tableName="emp" domainObjectName="Emp">
    <!-- 强制指定某列的 Java 类型和 jdbcType -->
    <columnOverride column="salary"
                    property="salary"
                    javaType="java.math.BigDecimal"
                    jdbcType="DECIMAL"/>
    <!-- 强制指定枚举类型 -->
     <columnOverride column="gender"
                    property="gender"
                    javaType="com.example.enums.Gender"
                    typeHandler="com.example.handler.GenderTypeHandler"/>
    <!-- 修改属性名（驼峰自定义） -->
    <columnOverride column="emp_name" property="name"/>
    <!-- 强制 BLOB 类型 -->
    <columnOverride column="content" isBlob="true" javaType="java.lang.String"/>
</table>

mybatis-generator-demo/
├── src/main/java/com/example/
│   ├── entity/
│   │   ├── Emp.java              ← 员工实体类
│   │   ├── EmpExample.java       ← 员工查询条件类
│   │   ├── Dept.java             ← 部门实体类
│   │   └── DeptExample.java      ← 部门查询条件类
│   ├── mapper/
 │   │   ├── EmpMapper.java        ← 员工 Mapper 接口
│   │   └── DeptMapper.java       ← 部门 Mapper 接口
│   └── generator/
│       └── Generator.java        ← 生成器启动类
├── src/main/resources/
│   ├── generatorConfig.xml       ← MBG 配置文件
│   ├── generator.properties      ← 属性文件
│   ├── mapper/
│   │   ├── EmpMapper.xml         ← 员工 SQL 映射
│   │   └── DeptMapper.xml        ← 部门 SQL 映射
│   └── mybatis-config.xml        ← MyBatis 主配置
└── pom.xml

 public class EmpExample {
     protected String orderByClause;          // 排序字段
     protected boolean distinct;              // 是否去重
     protected List<Criteria> oredCriteria;   // OR 条件列表
     // 设置排序
     public void setOrderByClause(String orderByClause) { ... }
     // 设置去重
    public void setDistinct(boolean distinct) { ... }
    // 获取 OR 条件列表
    public List<Criteria> getOredCriteria() { ... }
    // 创建一个 OR 条件（相当于 OR (...)）
    public Criteria or() { ... }
    // 添加一个 Criteria 到 OR 列表
    public void or(Criteria criteria) { ... }
    // 创建一个 Criteria（相当于一个 AND 条件组）
    public Criteria createCriteria() { ... }
    // = createCriteria()，内部调用
    protected Criteria createCriteriaInternal() { ... }
    // 清空所有条件
    public void clear() { ... }
    // ====== Criteria 内部类 ======
    public abstract static class GeneratedCriteria {
        // 等于
        public Criteria andEmpIdEqualTo(Integer value) { ... }
        // 不等于
        public Criteria andEmpIdNotEqualTo(Integer value) { ... }
        // 大于
        public Criteria andEmpIdGreaterThan(Integer value) { ... }
        // 大于等于
        public Criteria andEmpIdGreaterThanOrEqualTo(Integer value) { ... }
        // 小于
        public Criteria andEmpIdLessThan(Integer value) { ... }
        // 小于等于
        public Criteria andEmpIdLessThanOrEqualTo(Integer value) { ... }
        // IN
        public Criteria andEmpIdIn(List<Integer> values) { ... }
        // NOT IN
        public Criteria andEmpIdNotIn(List<Integer> values) { ... }
        // BETWEEN
        public Criteria andEmpIdBetween(Integer value1, Integer value2) { ... }
        // NOT BETWEEN
        public Criteria andEmpIdNotBetween(Integer value1, Integer value2) { ... }
        // LIKE
        public Criteria andEmpNameLike(String value) { ... }
        // NOT LIKE
        public Criteria andEmpNameNotLike(String value) { ... }
        // IS NULL
        public Criteria andEmpNameIsNull() { ... }
        // IS NOT NULL
        public Criteria andEmpNameIsNotNull() { ... }
        // ... 每个字段都有以上方法
    }
    // ====== Criteria 继承类 ======
    public static class Criteria extends GeneratedCriteria {
        // ...
    }
}

 // ====== 1. 查询所有 ======
 List<Emp> allEmps = empMapper.selectByExample(new EmpExample());
 // ====== 2. 按主键查询 ======
 Emp emp = empMapper.selectByPrimaryKey(1);
 // ====== 3. 等值查询：gender = 'M' ======
 EmpExample example = new EmpExample();
 example.createCriteria().andGenderEqualTo("M");
List<Emp> males = empMapper.selectByExample(example);
// ====== 4. 多条件 AND 查询 ======
// WHERE gender = 'M' AND salary > 10000 AND dept_id = 1
EmpExample example = new EmpExample();
example.createCriteria()
        .andGenderEqualTo("M")
        .andSalaryGreaterThan(new BigDecimal("10000"))
        .andDeptIdEqualTo(1);
List<Emp> result = empMapper.selectByExample(example);
// ====== 5. OR 条件查询 ======
// WHERE (gender = 'M' AND salary > 15000) OR (gender = 'F' AND salary > 12000)
EmpExample example = new EmpExample();
example.createCriteria()
        .andGenderEqualTo("M")
        .andSalaryGreaterThan(new BigDecimal("15000"));
example.or()
        .andGenderEqualTo("F")
        .andSalaryGreaterThan(new BigDecimal("12000"));
List<Emp> result = empMapper.selectByExample(example);
// ====== 6. LIKE 查询 ======
// WHERE emp_name LIKE '%张%'
EmpExample example = new EmpExample();
example.createCriteria().andEmpNameLike("%张%");
List<Emp> result = empMapper.selectByExample(example);
// ====== 7. IN 查询 ======
// WHERE dept_id IN (1, 2, 3)
EmpExample example = new EmpExample();
example.createCriteria().andDeptIdIn(Arrays.asList(1, 2, 3));
List<Emp> result = empMapper.selectByExample(example);
// ====== 8. BETWEEN 查询 ======
// WHERE salary BETWEEN 8000 AND 20000
EmpExample example = new EmpExample();
example.createCriteria()
        .andSalaryBetween(new BigDecimal("8000"), new BigDecimal("20000"));
List<Emp> result = empMapper.selectByExample(example);
// ====== 9. IS NULL 查询 ======
// WHERE email IS NULL
EmpExample example = new EmpExample();
example.createCriteria().andEmailIsNull();
List<Emp> result = empMapper.selectByExample(example);
// ====== 10. 排序 ======
// ORDER BY salary DESC
EmpExample example = new EmpExample();
example.setOrderByClause("salary DESC");
List<Emp> result = empMapper.selectByExample(example);
// ====== 11. 去重 ======
EmpExample example = new EmpExample();
example.setDistinct(true);
example.setOrderByClause("dept_id");
List<Emp> result = empMapper.selectByExample(example);
// ====== 12. 条件删除 ======
// DELETE FROM emp WHERE dept_id = 3
EmpExample example = new EmpExample();
example.createCriteria().andDeptIdEqualTo(3);
empMapper.deleteByExample(example);
// ====== 13. 条件更新 ======
// UPDATE emp SET salary = 20000 WHERE dept_id = 1
EmpExample example = new EmpExample();
example.createCriteria().andDeptIdEqualTo(1);
Emp record = new Emp();
record.setSalary(new BigDecimal("20000"));
empMapper.updateByExampleSelective(record, example);
// ====== 14. 条件计数 ======
EmpExample example = new EmpExample();
example.createCriteria().andGenderEqualTo("M");
long count = empMapper.countByExample(example);

 package com.example.generator;
 import org.mybatis.generator.api.IntrospectedColumn;
 import org.mybatis.generator.api.IntrospectedTable;
 import org.mybatis.generator.api.dom.java.*;
 import org.mybatis.generator.api.dom.xml.XmlElement;
 import org.mybatis.generator.internal.DefaultCommentGenerator;
 import java.util.Properties;
/**
 * 自定义注释生成器
 * 生成数据库字段注释到 Java 实体类中
 */
public class CustomCommentGenerator extends DefaultCommentGenerator {
    private boolean addRemarkComments;
    @Override
    public void addConfigurationProperties(Properties properties) {
        super.addConfigurationProperties(properties);
        this.addRemarkComments = Boolean.parseBoolean(
            properties.getProperty("addRemarkComments"));
    }
    /**
     * 给字段添加注释（数据库列注释）
     */
    @Override
    public void addFieldComment(Field field,
                                 IntrospectedTable introspectedTable,
                                 IntrospectedColumn introspectedColumn) {
        if (addRemarkComments) {
            String remark = introspectedColumn.getRemarks();
            if (remark != null && !remark.trim().isEmpty()) {
                field.addJavaDocLine("/**");
                field.addJavaDocLine(" * " + remark);
                field.addJavaDocLine(" */");
            }
        }
    }
    /**
     * 给类添加注释（表注释）
     */
    @Override
    public void addClassComment(InnerClass innerClass,
                                 IntrospectedTable introspectedTable) {
        String remark = introspectedTable.getRemarks();
        innerClass.addJavaDocLine("/**");
        if (remark != null && !remark.trim().isEmpty()) {
            innerClass.addJavaDocLine(" * " + remark);
        }
        innerClass.addJavaDocLine(" * 对应数据库表: " +
            introspectedTable.getFullyQualifiedTable());
        innerClass.addJavaDocLine(" */");
    }
    /**
     * 给 getter 方法添加注释
     */
    @Override
    public void addGetterComment(Method method,
                                  IntrospectedTable introspectedTable,
                                  IntrospectedColumn introspectedColumn) {
        // 不生成 getter 注释（保持简洁）
    }
    /**
     * 给 setter 方法添加注释
     */
    @Override
    public void addSetterComment(Method method,
                                  IntrospectedTable introspectedTable,
                                  IntrospectedColumn introspectedColumn) {
        // 不生成 setter 注释（保持简洁）
    }
}

 <context id="mysqlContext" targetRuntime="MyBatis3">
     <!-- 使用自定义注释生成器 -->
     <commentGenerator type="com.example.generator.CustomCommentGenerator">
         <property name="suppressAllComments" value="false"/>
         <property name="suppressDate" value="true"/>
         <property name="addRemarkComments" value="true"/>
     </commentGenerator>
    <!-- ... 其他配置 ... -->
</context>

 /**
  * 员工表
  * 对应数据库表: mybatis_demo.emp
  */
 public class Emp {
     /**
      * 员工ID
      */
    private Integer empId;
    /**
     * 员工姓名
     */
    private String empName;
    /**
     * 性别 M-男 F-女
     */
    private String gender;
    // ... getter/setter
}

 MBG 生成流程
     ↓
 ┌─────────────────────────────────┐
 │  阶段1: Model Class 生成         │ ← Plugin 可拦截
 ├─────────────────────────────────┤
 │  阶段2: SQL Map (XML) 生成       │ ← Plugin 可拦截
 ├─────────────────────────────────┤
 │  阶段3: Client (Mapper) 生成     │ ← Plugin 可拦截
 ├─────────────────────────────────┤
│  阶段4: Example Class 生成       │ ← Plugin 可拦截
└─────────────────────────────────┘

 package com.example.generator;
 import org.mybatis.generator.api.IntrospectedTable;
 import org.mybatis.generator.api.PluginAdapter;
 import org.mybatis.generator.api.dom.java.*;
 import java.util.List;
 /**
 * 自定义 Lombok 插件
 * 让生成的实体类使用 @Data 注解，去掉 getter/setter
 */
public class LombokPlugin extends PluginAdapter {
    @Override
    public boolean validate(List<String> warnings) {
        return true;
    }
    /**
     * 给实体类添加 Lombok 注解
     */
    @Override
    public boolean modelBaseRecordClassGenerated(TopLevelClass topLevelClass,
                                                  IntrospectedTable introspectedTable)
     {
        // 添加 @Data 注解
        topLevelClass.addImportedType("lombok.Data");
        topLevelClass.addAnnotation("@Data");
        // 添加 @Builder 注解（可选）
        topLevelClass.addImportedType("lombok.Builder");
        topLevelClass.addAnnotation("@Builder");
        // 添加 @NoArgsConstructor
        topLevelClass.addImportedType("lombok.NoArgsConstructor");
        topLevelClass.addAnnotation("@NoArgsConstructor");
        // 添加 @AllArgsConstructor
        topLevelClass.addImportedType("lombok.AllArgsConstructor");
        topLevelClass.addAnnotation("@AllArgsConstructor");
        return true;
    }
    /**
     * 给主键类添加 Lombok 注解（如果有）
     */
    @Override
    public boolean modelPrimaryKeyClassGenerated(TopLevelClass topLevelClass,
                                                  IntrospectedTable introspectedTable)
     {
        topLevelClass.addImportedType("lombok.Data");
        topLevelClass.addAnnotation("@Data");
        return true;
    }
    /**
     * 禁止生成 getter 方法（由 Lombok @Data 提供）
     */
    @Override
    public boolean modelGetterMethodGenerated(Method method,
                                               TopLevelClass topLevelClass,
                                               IntrospectedColumn introspectedColumn,
                                               IntrospectedTable introspectedTable,
                                               ModelClassType modelClassType) {
        return false;  // false = 不生成 getter
    }
    /**
     * 禁止生成 setter 方法
     */
    @Override
    public boolean modelSetterMethodGenerated(Method method,
                                               TopLevelClass topLevelClass,
                                               IntrospectedColumn introspectedColumn,
                                               IntrospectedTable introspectedTable,
                                               ModelClassType modelClassType) {
        return false;  // false = 不生成 setter
    }
}

 <context id="mysqlContext" targetRuntime="MyBatis3">
     <!-- 内置插件 -->
     <plugin type="org.mybatis.generator.plugins.SerializablePlugin"/>
     <plugin type="org.mybatis.generator.plugins.EqualsAndHashCodePlugin"/>
     <!-- ★ 自定义 Lombok 插件 -->
     <plugin type="com.example.generator.LombokPlugin"/>
    <!-- ★ 重命名 Example 类为 Query -->
    <plugin type="org.mybatis.generator.plugins.RenameExampleClassPlugin">
        <property name="searchString" value="Example$"/>
        <property name="replaceString" value="Query"/>
    </plugin>
    <!-- 自定义注释生成器 -->
    <commentGenerator type="com.example.generator.CustomCommentGenerator">
        <property name="suppressAllComments" value="false"/>
        <property name="addRemarkComments" value="true"/>
    </commentGenerator>
    <!-- ... 其他配置 ... -->
</context>

package com.example.generator;
import org.mybatis.generator.api.IntrospectedTable;
import org.mybatis.generator.api.PluginAdapter;
import org.mybatis.generator.api.dom.java.FullyQualifiedJavaType;
import org.mybatis.generator.api.dom.java.Interface;
 import org.mybatis.generator.api.dom.java.TopLevelClass;
 import java.util.List;
/**
 * 让所有生成的 Mapper 接口继承自定义的 BaseMapper
 */
public class BaseMapperPlugin extends PluginAdapter {
    private String baseMapperPackage;
    @Override
    public boolean validate(List<String> warnings) {
        baseMapperPackage = properties.getProperty("baseMapperPackage");
        return baseMapperPackage != null && !baseMapperPackage.trim().isEmpty();
    }
    @Override
    public boolean clientGenerated(Interface interfaze,
                                    TopLevelClass topLevelClass,
                                    IntrospectedTable introspectedTable) {
        // 导入 BaseMapper
        FullyQualifiedJavaType baseMapperType =
            new FullyQualifiedJavaType(baseMapperPackage);
        interfaze.addImportedType(baseMapperType);
        // 让 Mapper 继承 BaseMapper<实体类>
        FullyQualifiedJavaType entityType =
            new FullyQualifiedJavaType(introspectedTable.getBaseRecordType());
        interfaze.addSuperInterface(
            new FullyQualifiedJavaType(baseMapperPackage + "<" +
     entityType.getShortName() + ">"));
        return true;
    }
}
<plugin type="com.example.generator.BaseMapperPlugin">
    <property name="baseMapperPackage" value="com.example.mapper.BaseMapper"/>
</plugin>

 <dependencies>
     <!-- MyBatis-Plus（包含 MyBatis） -->
     <dependency>
         <groupId>com.baomidou</groupId>
         <artifactId>mybatis-plus-boot-starter</artifactId>
         <version>3.5.7</version>
     </dependency>
     <!-- MP 代码生成器核心 -->
    <dependency>
        <groupId>com.baomidou</groupId>
        <artifactId>mybatis-plus-generator</artifactId>
        <version>3.5.7</version>
    </dependency>
    <!-- 模板引擎（Freemarker / Velocity / Beetl 任选其一） -->
    <dependency>
        <groupId>org.freemarker</groupId>
        <artifactId>freemarker</artifactId>
        <version>2.3.32</version>
    </dependency>
    <!-- MySQL 驱动 -->
    <dependency>
        <groupId>com.mysql</groupId>
        <artifactId>mysql-connector-j</artifactId>
        <version>8.0.33</version>
    </dependency>
    <!-- Lombok（可选） -->
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.18.34</version>
        <scope>provided</scope>
    </dependency>
    <!-- Swagger / SpringDoc（可选） -->
    <dependency>
        <groupId>org.springdoc</groupId>
        <artifactId>springdoc-openapi-starter-webmvc-ui</artifactId>
        <version>2.5.0</version>
    </dependency>
</dependencies>

 package com.example.generator;
 import com.baomidou.mybatisplus.generator.FastAutoGenerator;
 import com.baomidou.mybatisplus.generator.config.OutputFile;
 import com.baomidou.mybatisplus.generator.config.rules.NamingStrategy;
 import com.baomidou.mybatisplus.generator.engine.FreemarkerTemplateEngine;
 import java.util.Collections;
public class MpGenerator {
    public static void main(String[] args) {
        FastAutoGenerator.create(
                "jdbc:mysql://localhost:3306/mybatis_demo?
     useSSL=false&serverTimezone=Asia/Shanghai",
                "root",
                "123456")
            // ====== 全局配置 ======
            .globalConfig(builder -> {
                builder.author("example")               // 作者
                       .outputDir("src/main/java")      // 输出目录
                       .enableSwagger()                  // 开启 Swagger 注解
                       .commentDate("yyyy-MM-dd");       // 注释日期格式
            })
            // ====== 包配置 ======
            .packageConfig(builder -> {
                builder.parent("com.example")           // 父包名
                       .entity("entity")                // 实体类包名
                       .mapper("mapper")                // Mapper 包名
                       .service("service")              // Service 包名
                       .serviceImpl("service.impl")     // Service 实现包名
                       .controller("controller")        // Controller 包名
                       .xml("mapper")                   // XML 资源路径
                       .pathInfo(Collections.singletonMap(
                           OutputFile.xml,
                           "src/main/resources/mapper")); // XML 输出目录
            })
            // ====== 策略配置 ======
            .strategyConfig(builder -> {
                builder.addInclude("emp", "dept")       // 表名（可变参数）
                       .addTablePrefix("t_", "sys_")    // 过滤表前缀
                       .entityBuilder()
                       .naming(NamingStrategy.underline_to_camel)  // 下划线转驼峰
                       .columnNaming(NamingStrategy.underline_to_camel)
                       .enableLombok()                   // 使用 Lombok
                       .enableTableFieldAnnotation()     // 生成字段注解
                       .logicDeleteColumnName("deleted") // 逻辑删除字段
                       .versionColumnName("version")     // 乐观锁字段
                       .idType(IdType.AUTO)              // 主键策略
                       .formatFileName("%s")             // 实体类名格式
                       .mapperBuilder()
                       .enableMapperAnnotation()          // 生成 @Mapper 注解
                       .formatMapperFileName("%sMapper")   // Mapper 文件名格式
                       .formatXmlFileName("%sMapper")      // XML 文件名格式
                       .serviceBuilder()
                       .formatServiceFileName("%sService")     // Service 接口名
                       .formatServiceImplFileName("%sServiceImpl") // Service 实现名
                       .controllerBuilder()
                       .enableRestStyle();                // 生成 @RestController
            })
            // ====== 模板引擎 ======
            .templateEngine(new FreemarkerTemplateEngine())
            // ====== 执行 ======
            .execute();
        System.out.println("✅ MyBatis-Plus 代码生成完成！");
    }
}

 src/main/java/com/example/
 ├── entity/
 │   ├── Emp.java              ← @Data + @TableName + 字段注解
 │   └── Dept.java
 ├── mapper/
 │   ├── EmpMapper.java        ← extends BaseMapper<Emp>
 │   └── DeptMapper.java
 ├── service/
 │   ├── EmpService.java       ← extends IService<Emp>
│   └── impl/
│       └── EmpServiceImpl.java  ← extends ServiceImpl<EmpMapper, Emp>
└── controller/
    ├── EmpController.java    ← @RestController
    └── DeptController.java
src/main/resources/
└── mapper/
    ├── EmpMapper.xml
    └── DeptMapper.xml

package com.example.generator;
import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.generator.AutoGenerator;
 import com.baomidou.mybatisplus.generator.config.*;
 import com.baomidou.mybatisplus.generator.config.rules.NamingStrategy;
 import com.baomidou.mybatisplus.generator.engine.FreemarkerTemplateEngine;
 public class MpFullGenerator {
    public static void main(String[] args) {
        // ====== 1. 数据源配置 ======
        DataSourceConfig dataSourceConfig = DataSourceConfig.builder(
                "jdbc:mysql://localhost:3306/mybatis_demo?
     useSSL=false&serverTimezone=Asia/Shanghai",
                "com.mysql.cj.jdbc.Driver",
                "root",
                "123456")
            .build();
        // ====== 2. 全局配置 ======
        GlobalConfig globalConfig = GlobalConfig.builder()
                .author("example")
                .outputDir("src/main/java")
                .enableSwagger()                    // Swagger 注解
                .disableOpenDir()                    // 生成后不自动打开目录
                .commentDate("yyyy-MM-dd")
                .dateType(DateType.TIME_PACK)        // 使用 java.time 包
                .build();
        // ====== 3. 包配置 ======
        PackageConfig packageConfig = PackageConfig.builder()
                .parent("com.example")
                .moduleName("system")               // 模块名（会加到包路径中）
                .entity("entity")
                .mapper("mapper")
                .service("service")
                .serviceImpl("service.impl")
                .controller("controller")
                .xml("mapper.xml")
                .pathInfo(java.util.Collections.singletonMap(
                    OutputFile.xml,
                    "src/main/resources/mapper"))
                .build();
        // ====== 4. 模板配置 ======
        TemplateConfig templateConfig = TemplateConfig.builder()
                .entity("templates/entity.java")    // 使用自定义模板
                .mapper("templates/mapper.java")
                .xml("templates/mapper.xml")
                .service("templates/service.java")
                .serviceImpl("templates/serviceImpl.java")
                .controller("templates/controller.java")
                .build();
        // ====== 5. 策略配置 ======
         StrategyConfig strategyConfig = StrategyConfig.builder()
                 .addInclude("emp", "dept")          // 要生成的表
                 .addTablePrefix("t_", "sys_")       // 过滤表前缀
                 .addTableSuffix("_tab")             // 过滤表后缀
                 // 实体策略
                 .entityBuilder()
                 .naming(NamingStrategy.underline_to_camel)
                 .columnNaming(NamingStrategy.underline_to_camel)
                 .enableLombok()                     // Lombok 注解
                 .enableTableFieldAnnotation()       // @TableField 注解
                 .enableActiveRecord()               // ActiveRecord 模式
                 .enableFileOverride()               // 覆盖已有文件
                 .logicDeleteColumnName("deleted")   // 逻辑删除
                 .versionColumnName("version")       // 乐观锁
                 .idType(IdType.AUTO)                // 主键策略
                 .formatFileName("%s")               // 实体类名格式
                 .superClass("com.example.BaseEntity")  // 父类
                 // Mapper 策略
                 .mapperBuilder()
                 .enableMapperAnnotation()           // @Mapper 注解
                 .enableBaseResultMap()              // 生成 BaseResultMap
                 .enableBaseColumnList()             // 生成 BaseColumnList
                 .formatMapperFileName("%sMapper")
                 .formatXmlFileName("%sMapper")
                 // Service 策略
                 .serviceBuilder()
                 .formatServiceFileName("%sService")
                 .formatServiceImplFileName("%sServiceImpl")
                 .superServiceClass("com.example.BaseService")
                 .superServiceImplClass("com.example.BaseServiceImpl")
                 // Controller 策略
                 .controllerBuilder()
                 .enableRestStyle()                  // @RestController
                 .enableHyphenStyle()                // URL 连字符风格
                 .formatFileName("%sController")
                 .build();
         // ====== 6. 注入配置（自定义变量） ======
         InjectionConfig injectionConfig = InjectionConfig.builder()
                 .customMap(java.util.Map.of(
                     "author", "example",
                     "version", "1.0.0"))
                 .build();
        // ====== 7. 组装执行 ======
        AutoGenerator generator = new AutoGenerator(dataSourceConfig);
        generator.global(globalConfig);
        generator.packageInfo(packageConfig);
        generator.template(templateConfig);
        generator.strategy(strategyConfig);
        generator.injection(injectionConfig);
        generator.templateEngine(new FreemarkerTemplateEngine());
        generator.execute();
        System.out.println("✅ 代码生成完成！");
    }
}

 // MySQL 8.x 类型映射自定义
 DataSourceConfig dataSourceConfig = DataSourceConfig.builder(
         url, driver, username, password)
     .typeConvert(new ITypeConvert() {
         @Override
         public IColumnType executeTypeConvert(TableInfo tableInfo, String fieldName,
     String fieldType) {
             // 自定义类型映射
             if ("tinyint(1)".equalsIgnoreCase(fieldType)) {
                 return DbColumnType.BOOLEAN;
            }
            if ("json".equalsIgnoreCase(fieldType)) {
                return DbColumnType.OBJECT;
            }
            // 默认使用 MP 内置映射
            return TypeConverts.useDefault(tableInfo, fieldName, fieldType);
        }
    })
    .build();

 package ${package.Entity};
 <#list table.importPackages as pkg>
 import ${pkg};
 </#list>
 <#if swagger2>
 import io.swagger.v3.oas.annotations.media.Schema;
 </#if>
 <#if entityLombokAnnotations>
import lombok.Data;
import lombok.experimental.Accessors;
</#if>
/**
 * <p>
 * ${table.comment!}
 * </p>
 *
 * @author ${author}
 * @since ${date}
 */
<#if entityLombokAnnotations>
@Data
@Accessors(chain = true)
</#if>
<#if swagger2>
@Schema(description = "${table.comment!}")
</#if>
@TableName("${schemaName}${table.name}")
public class ${entity} implements Serializable {
    private static final long serialVersionUID = 1L;
<#-- ----------  BEGIN 字段循环遍历  ---------->
<#list table.fields as field>
    <#if field.keyFlag>
        <#if field.keyIdentityFlag>
    @TableId(value = "${field.annotationColumnName}", type = IdType.AUTO)
        <#elseif idType??>
    @TableId(value = "${field.annotationColumnName}", type = IdType.${idType})
        <#else>
    @TableId(value = "${field.annotationColumnName}", type = IdType.ASSIGN_ID)
        </#if>
    <#elseif field.fill??>
    <#-- 通用填充字段 -->
    @TableField(value = "${field.annotationColumnName}", fill =
     FieldFill.${field.fill})
    <#elseif !field.propertyType?ends_with("Serializable")>
    @TableField("${field.annotationColumnName}")
    </#if>
    <#if swagger2>
    @Schema(description = "${field.comment!}")
    </#if>
    private ${field.propertyType} ${field.propertyName};
</#list>
<#------------  END 字段循环遍历  ---------->
<#if !entityLombokAnnotations>
    <#list table.fields as field>
        <#if field.propertyType == "boolean">
            <#assign getprefix="is"/>
        <#else>
            <#assign getprefix="get"/>
        </#if>
    public ${field.propertyType} ${getprefix}${field.capitalPropertyName}() {
        return ${field.propertyName};
    }
    public void set${field.capitalPropertyName}(${field.propertyType}
     ${field.propertyName}) {
        this.${field.propertyName} = ${field.propertyName};
    }
    </#list>
</#if>
}

 package ${package.Controller};
 import ${package.Entity}.${entity};
 import ${package.Service}.${entity}Service;
 <#if swagger2>
 import io.swagger.v3.oas.annotations.tags.Tag;
 import io.swagger.v3.oas.annotations.Operation;
 </#if>
 import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
import java.util.List;
/**
 * <p>
 * ${table.comment!} 前端控制器
 * </p>
 *
 * @author ${author}
 * @since ${date}
 */
<#if swagger2>
@Tag(name = "${table.comment!}")
</#if>
@RestController
@RequestMapping("/${table.entityPath}")
public class ${entity}Controller {
    @Autowired
    private ${entity}Service ${table.entityPath}Service;
    @Operation(summary = "查询所有")
    @GetMapping
    public List<${entity}> list() {
        return ${table.entityPath}Service.list();
    }
    @Operation(summary = "根据ID查询")
    @GetMapping("/{id}")
    public ${entity} getById(@PathVariable ${entity} ${table.entityPath}) {
        return ${table.entityPath}Service.getById(${table.entityPath});
    }
    @Operation(summary = "新增")
    @PostMapping
    public boolean save(@RequestBody ${entity} ${table.entityPath}) {
        return ${table.entityPath}Service.save(${table.entityPath});
    }
    @Operation(summary = "修改")
    @PutMapping
    public boolean update(@RequestBody ${entity} ${table.entityPath}) {
        return ${table.entityPath}Service.updateById(${table.entityPath});
    }
    @Operation(summary = "根据ID删除")
    @DeleteMapping("/{id}")
    public boolean delete(@PathVariable ${entity} ${table.entityPath}) {
        return ${table.entityPath}Service.removeById(${table.entityPath});
    }
}

 <dependencies>
     <!-- Spring Boot Starter -->
     <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-web</artifactId>
     </dependency>
     <!-- MyBatis Spring Boot Starter -->
     <dependency>
        <groupId>org.mybatis.spring.boot</groupId>
        <artifactId>mybatis-spring-boot-starter</artifactId>
        <version>3.0.3</version>
    </dependency>
    <!-- MySQL -->
    <dependency>
        <groupId>com.mysql</groupId>
        <artifactId>mysql-connector-j</artifactId>
        <scope>runtime</scope>
    </dependency>
</dependencies>
<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
        <!-- MBG 插件 -->
        <plugin>
            <groupId>org.mybatis.generator</groupId>
            <artifactId>mybatis-generator-maven-plugin</artifactId>
            <version>1.4.2</version>
            <executions>
                <!-- 可选：绑定到 generate-sources 阶段自动执行 -->
                <execution>
                    <id>Generate MyBatis Artifacts</id>
                    <goals>
                        <goal>generate</goal>
                    </goals>
                    <!-- 取消注释则每次构建自动生成 -->
                    <!-- <phase>generate-sources</phase> -->
                </execution>
            </executions>
            <configuration>
                <configurationFile>
                    src/main/resources/generator/generatorConfig.xml
                </configurationFile>
                <overwrite>true</overwrite>
                <verbose>true</verbose>
            </configuration>
            <dependencies>
                <dependency>
                    <groupId>com.mysql</groupId>
                    <artifactId>mysql-connector-j</artifactId>
                    <version>8.0.33</version>
                </dependency>
            </dependencies>
        </plugin>
    </plugins>
</build>

 <dependencies>
     <dependency>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-web</artifactId>
     </dependency>
     <dependency>
         <groupId>com.baomidou</groupId>
         <artifactId>mybatis-plus-spring-boot3-starter</artifactId>
        <version>3.5.7</version>
    </dependency>
    <dependency>
        <groupId>com.baomidou</groupId>
        <artifactId>mybatis-plus-generator</artifactId>
        <version>3.5.7</version>
    </dependency>
    <dependency>
        <groupId>org.freemarker</groupId>
        <artifactId>freemarker</artifactId>
    </dependency>
    <dependency>
        <groupId>com.mysql</groupId>
        <artifactId>mysql-connector-j</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <optional>true</optional>
    </dependency>
</dependencies>