Mybatis Plus最新代码生成器AutoGenerator，更简单更高效！

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MyBatis-Plus（简称 MP）是一个 MyBatis 的增强工具，在 MyBatis 的基础上只做增强不做改变，为简化开发、提高效率而生。

今天的主角是MP推出的一款代码生成器，本文主要来介绍一下它强大的代码生成功能。

一、概述

AutoGenerator 是 MyBatis Plus推出的代码生成器，可以快速生成Entity、Mapper、Mapper XML、Service、Controller等各个模块的代码，比Mybatis Generator更强大，开发效率更高。

以往我们使用mybatis generator生成代码正常需要配置mybatis-generator-config.xml，代码配置比较繁琐复杂，比如：

<generatorConfiguration>
    <context id="myContext" targetRuntime="MyBatis3" defaultModelType="flat">
    <span class="hljs-comment">&lt;!-- 注释 --&gt;</span>
    <span class="hljs-tag">&lt;<span class="hljs-name">commentGenerator</span>&gt;</span>
        <span class="hljs-comment">&lt;!-- 是否不生成注释 --&gt;</span>
        <span class="hljs-tag">&lt;<span class="hljs-name">property</span> <span class="hljs-attr">name</span>=<span class="hljs-string">"suppressAllComments"</span> <span class="hljs-attr">value</span>=<span class="hljs-string">"true"</span>/&gt;</span>
    <span class="hljs-tag">&lt;/<span class="hljs-name">commentGenerator</span>&gt;</span>

    <span class="hljs-comment">&lt;!-- jdbc连接 --&gt;</span>
    <span class="hljs-tag">&lt;<span class="hljs-name">jdbcConnection</span> <span class="hljs-attr">driverClass</span>=<span class="hljs-string">"com.mysql.cj.jdbc.Driver"</span> <span class="hljs-attr">connectionURL</span>=<span class="hljs-string">"jdbc:mysql://ip:3306/codingmoretiny02?useUnicode=true<span class="hljs-symbol">&amp;amp;</span>characterEncoding=utf-8<span class="hljs-symbol">&amp;amp;</span>serverTimezone=Asia/Shanghai<span class="hljs-symbol">&amp;amp;</span>useSSL=false"</span> <span class="hljs-attr">userId</span>=<span class="hljs-string">"codingmoretiny02"</span> <span class="hljs-attr">password</span>=<span class="hljs-string">"123456"</span>&gt;</span>
        <span class="hljs-comment">&lt;!--高版本的 mysql-connector-java 需要设置 nullCatalogMeansCurrent=true--&gt;</span>
        <span class="hljs-tag">&lt;<span class="hljs-name">property</span> <span class="hljs-attr">name</span>=<span class="hljs-string">"nullCatalogMeansCurrent"</span> <span class="hljs-attr">value</span>=<span class="hljs-string">"true"</span>/&gt;</span>
    <span class="hljs-tag">&lt;/<span class="hljs-name">jdbcConnection</span>&gt;</span>

    <span class="hljs-comment">&lt;!-- 类型转换 --&gt;</span>
    <span class="hljs-tag">&lt;<span class="hljs-name">javaTypeResolver</span>&gt;</span>
        <span class="hljs-tag">&lt;<span class="hljs-name">property</span> <span class="hljs-attr">name</span>=<span class="hljs-string">"forceBigDecimals"</span> <span class="hljs-attr">value</span>=<span class="hljs-string">"true"</span>/&gt;</span>
    <span class="hljs-tag">&lt;/<span class="hljs-name">javaTypeResolver</span>&gt;</span>

    <span class="hljs-comment">&lt;!-- 生成实体类地址 --&gt;</span>
    <span class="hljs-tag">&lt;<span class="hljs-name">javaModelGenerator</span> <span class="hljs-attr">targetPackage</span>=<span class="hljs-string">"com.codingmore.mbg.po"</span> <span class="hljs-attr">targetProject</span>=<span class="hljs-string">"src/main/java"</span>&gt;</span>
        <span class="hljs-comment">&lt;!-- 是否针对string类型的字段在set方法中进行修剪，默认false --&gt;</span>
        <span class="hljs-tag">&lt;<span class="hljs-name">property</span> <span class="hljs-attr">name</span>=<span class="hljs-string">"trimStrings"</span> <span class="hljs-attr">value</span>=<span class="hljs-string">"true"</span>/&gt;</span>
    <span class="hljs-tag">&lt;/<span class="hljs-name">javaModelGenerator</span>&gt;</span>


    <span class="hljs-comment">&lt;!-- 生成Mapper.xml文件 --&gt;</span>
    <span class="hljs-tag">&lt;<span class="hljs-name">sqlMapGenerator</span> <span class="hljs-attr">targetPackage</span>=<span class="hljs-string">"com.codingmore.mbg.mapper"</span> <span class="hljs-attr">targetProject</span>=<span class="hljs-string">"src/main/resources"</span>&gt;</span>
    <span class="hljs-tag">&lt;/<span class="hljs-name">sqlMapGenerator</span>&gt;</span>

    <span class="hljs-comment">&lt;!-- 生成 XxxMapper.java 接口--&gt;</span>
    <span class="hljs-tag">&lt;<span class="hljs-name">javaClientGenerator</span> <span class="hljs-attr">targetPackage</span>=<span class="hljs-string">"com.codingmore.mbg.dao"</span> <span class="hljs-attr">targetProject</span>=<span class="hljs-string">"src/main/java"</span> <span class="hljs-attr">type</span>=<span class="hljs-string">"XMLMAPPER"</span>&gt;</span>
    <span class="hljs-tag">&lt;/<span class="hljs-name">javaClientGenerator</span>&gt;</span>

    <span class="hljs-tag">&lt;<span class="hljs-name">table</span> <span class="hljs-attr">schema</span>=<span class="hljs-string">""</span> <span class="hljs-attr">tableName</span>=<span class="hljs-string">"user"</span> <span class="hljs-attr">domainObjectName</span>=<span class="hljs-string">"User"</span> <span class="hljs-attr">enableCountByExample</span>=<span class="hljs-string">"false"</span> <span class="hljs-attr">enableDeleteByExample</span>=<span class="hljs-string">"false"</span> <span class="hljs-attr">enableSelectByExample</span>=<span class="hljs-string">"false"</span> <span class="hljs-attr">enableUpdateByExample</span>=<span class="hljs-string">"false"</span> <span class="hljs-attr">selectByExampleQueryId</span>=<span class="hljs-string">"false"</span>&gt;</span>
    <span class="hljs-tag">&lt;/<span class="hljs-name">table</span>&gt;</span>
<span class="hljs-tag">&lt;/<span class="hljs-name">context</span>&gt;</span>

</generatorConfiguration>

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二、使用AutoGenerator

1. 初始化数据库表结构（以User用户表为例）

SET NAMES utf8mb4;
SET FOREIGN_KEY_CHECKS = 0;
– ----------------------------

– Table structure for user

– ----------------------------

DROP TABLE IF EXISTS <span class="hljs-keyword">user</span>;

CREATE TABLE <span class="hljs-keyword">user</span>  (

id bigint(20) NOT NULL AUTO_INCREMENT,

username varchar(50) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT ‘用户名’,

mobile varchar(100) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT ‘手机号’,

create_by varchar(64) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT ‘创建人’,

create_time datetime(0) NULL DEFAULT NULL COMMENT ‘创建时间’,

PRIMARY KEY (id) USING BTREE,

UNIQUE INDEX username(username) USING BTREE

) ENGINE = InnoDB AUTO_INCREMENT = 2 CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci COMMENT = ‘用户’ ROW_FORMAT = Dynamic;
SET FOREIGN_KEY_CHECKS = 1;
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2. 在 pom.xml 文件中添加 AutoGenerator 的依赖。

<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-generator</artifactId>
    <version>3.4.1</version>
</dependency>
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3. 添加模板引擎依赖，MyBatis-Plus 支持 Velocity（默认）、Freemarker、Beetl，这里使用Freemarker引擎。

<dependency>
   <groupId>org.freemarker</groupId>
   <artifactId>freemarker</artifactId>
   <version>2.3.31</version>
</dependency>
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4. 全局配置

package com.shardingspherejdbc.mybatisplus.genertor;
import com.baomidou.mybatisplus.annotation.FieldFill;

import com.baomidou.mybatisplus.annotation.IdType;

import com.baomidou.mybatisplus.generator.FastAutoGenerator;

import com.baomidou.mybatisplus.generator.config.OutputFile;

import com.baomidou.mybatisplus.generator.config.rules.DateType;

import com.baomidou.mybatisplus.generator.fill.Column;

import com.baomidou.mybatisplus.generator.fill.Property;

import com.shardingspherejdbc.mybatisplus.engine.EnhanceFreemarkerTemplateEngine;
import java.util.Collections;

import java.util.HashMap;

import java.util.Map;
/** * 代码生成器 * * @author: austin * @since: 2023/2/6 15:28 */

public class CodeGenerator {

public static void main(String[] args) {

// 数据源配置

FastAutoGenerator.create(“jdbc:mysql://localhost:3306/sharding-db0?serverTimezone=GMT%2B8”, “root”, “admin”)

.globalConfig(builder -> {

builder.author(“austin”)        // 设置作者

.enableSwagger()        // 开启 swagger 模式 默认值:false

.disableOpenDir()       // 禁止打开输出目录 默认值:true

.commentDate(“yyyy-MM-dd”) // 注释日期

.dateType(DateType.ONLY_DATE)   //定义生成的实体类中日期类型 DateType.ONLY_DATE 默认值: DateType.TIME_PACK

.outputDir(System.getProperty(“user.dir”) + “/src/main/java”); // 指定输出目录

})
            .packageConfig(builder -> {
                builder.parent(<span class="hljs-string">"com.shardingspherejdbc.mybatisplus"</span>) <span class="hljs-comment">// 父包模块名</span>
                        .controller(<span class="hljs-string">"controller"</span>)   <span class="hljs-comment">//Controller 包名 默认值:controller</span>
                        .entity(<span class="hljs-string">"entity"</span>)           <span class="hljs-comment">//Entity 包名 默认值:entity</span>
                        .service(<span class="hljs-string">"service"</span>)         <span class="hljs-comment">//Service 包名 默认值:service</span>
                        .mapper(<span class="hljs-string">"mapper"</span>)           <span class="hljs-comment">//Mapper 包名 默认值:mapper</span>
                        .other(<span class="hljs-string">"model"</span>)
                        <span class="hljs-comment">//.moduleName("xxx") // 设置父包模块名 默认值:无</span>
                        .pathInfo(Collections.singletonMap(OutputFile.xml, System.getProperty(<span class="hljs-string">"user.dir"</span>) + <span class="hljs-string">"/src/main/resources/mapper"</span>)); <span class="hljs-comment">// 设置mapperXml生成路径</span>
                <span class="hljs-comment">//默认存放在mapper的xml下</span>
            })

            .injectionConfig(consumer -&gt; {
                Map&lt;String, String&gt; customFile = <span class="hljs-keyword">new</span> <span class="hljs-title class_">HashMap</span>&lt;&gt;();
                <span class="hljs-comment">// DTO、VO</span>
                customFile.put(<span class="hljs-string">"DTO.java"</span>, <span class="hljs-string">"/templates/entityDTO.java.ftl"</span>);
                customFile.put(<span class="hljs-string">"VO.java"</span>, <span class="hljs-string">"/templates/entityVO.java.ftl"</span>);

                consumer.customFile(customFile);
            })

            .strategyConfig(builder -&gt; {
                builder.addInclude(<span class="hljs-string">"user"</span>) <span class="hljs-comment">// 设置需要生成的表名 可边长参数“user”, “user1”</span>
                        .addTablePrefix(<span class="hljs-string">"tb_"</span>, <span class="hljs-string">"gms_"</span>) <span class="hljs-comment">// 设置过滤表前缀</span>
                        .serviceBuilder()<span class="hljs-comment">//service策略配置</span>
                        .formatServiceFileName(<span class="hljs-string">"%sService"</span>)
                        .formatServiceImplFileName(<span class="hljs-string">"%sServiceImpl"</span>)
                        .entityBuilder()<span class="hljs-comment">// 实体类策略配置</span>
                        .idType(IdType.ASSIGN_ID)<span class="hljs-comment">//主键策略 雪花算法自动生成的id</span>
                        .addTableFills(<span class="hljs-keyword">new</span> <span class="hljs-title class_">Column</span>(<span class="hljs-string">"create_time"</span>, FieldFill.INSERT)) <span class="hljs-comment">// 自动填充配置</span>
                        .addTableFills(<span class="hljs-keyword">new</span> <span class="hljs-title class_">Property</span>(<span class="hljs-string">"update_time"</span>, FieldFill.INSERT_UPDATE))
                        .enableLombok() <span class="hljs-comment">//开启lombok</span>
                        .logicDeleteColumnName(<span class="hljs-string">"deleted"</span>)<span class="hljs-comment">// 说明逻辑删除是哪个字段</span>
                        .enableTableFieldAnnotation()<span class="hljs-comment">// 属性加上注解说明</span>
                        .controllerBuilder() <span class="hljs-comment">//controller 策略配置</span>
                        .formatFileName(<span class="hljs-string">"%sController"</span>)
                        .enableRestStyle() <span class="hljs-comment">// 开启RestController注解</span>
                        .mapperBuilder()<span class="hljs-comment">// mapper策略配置</span>
                        .formatMapperFileName(<span class="hljs-string">"%sMapper"</span>)
                        .enableMapperAnnotation()<span class="hljs-comment">//@mapper注解开启</span>
                        .formatXmlFileName(<span class="hljs-string">"%sMapper"</span>);
            })


            <span class="hljs-comment">// 使用Freemarker引擎模板，默认的是Velocity引擎模板</span>
            <span class="hljs-comment">//.templateEngine(new FreemarkerTemplateEngine())</span>
            .templateEngine(<span class="hljs-keyword">new</span> <span class="hljs-title class_">EnhanceFreemarkerTemplateEngine</span>())
            .execute();

}

}

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5. 自定义模板生成DTO、VO

package com.shardingspherejdbc.mybatisplus.engine;
import com.baomidou.mybatisplus.generator.config.OutputFile;

import com.baomidou.mybatisplus.generator.config.po.TableInfo;

import com.baomidou.mybatisplus.generator.engine.FreemarkerTemplateEngine;

import org.springframework.stereotype.Component;
import java.io.File;

import java.util.Map;
/** * 代码生成器支持自定义[DTO\VO等]模版 * * @author: austin * @since: 2023/2/9 13:00 */

@Component

public class EnhanceFreemarkerTemplateEngine extends FreemarkerTemplateEngine {
<span class="hljs-meta">@Override</span>
<span class="hljs-keyword">protected</span> <span class="hljs-built_in">void</span> <span class="hljs-title function_">outputCustomFile</span>(<span class="hljs-params"><span class="hljs-built_in">Map</span>&lt;<span class="hljs-built_in">String</span>, <span class="hljs-built_in">String</span>&gt; customFile, TableInfo tableInfo, <span class="hljs-built_in">Map</span>&lt;<span class="hljs-built_in">String</span>, <span class="hljs-built_in">Object</span>&gt; objectMap</span>) {
    <span class="hljs-title class_">String</span> entityName = tableInfo.<span class="hljs-title function_">getEntityName</span>();
    <span class="hljs-title class_">String</span> otherPath = <span class="hljs-variable language_">this</span>.<span class="hljs-title function_">getPathInfo</span>(<span class="hljs-title class_">OutputFile</span>.<span class="hljs-property">other</span>);
    customFile.<span class="hljs-title function_">forEach</span>((key, value) -&gt; {
        <span class="hljs-title class_">String</span> fileName = <span class="hljs-title class_">String</span>.<span class="hljs-title function_">format</span>(otherPath + <span class="hljs-title class_">File</span>.<span class="hljs-property">separator</span> + entityName + <span class="hljs-string">"%s"</span>, key);
        <span class="hljs-variable language_">this</span>.<span class="hljs-title function_">outputFile</span>(<span class="hljs-keyword">new</span> <span class="hljs-title class_">File</span>(fileName), objectMap, value, <span class="hljs-literal">true</span>);
    });
}

}

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未生成代码前的项目目录如下：

运行CodeGenerator生成代码：

14:20:21.127 [main] DEBUG com.baomidou.mybatisplus.generator.AutoGenerator - ==========================准备生成文件...==========================
14:20:22.053 [main] DEBUG com.baomidou.mybatisplus.generator.config.querys.MySqlQuery - 执行SQL:show table status WHERE 1=1  AND NAME IN ('user')
14:20:22.081 [main] DEBUG com.baomidou.mybatisplus.generator.config.querys.MySqlQuery - 返回记录数:1,耗时(ms):26
14:20:22.167 [main] DEBUG com.baomidou.mybatisplus.generator.config.querys.MySqlQuery - 执行SQL:show full fields from `user`
14:20:22.171 [main] WARN com.baomidou.mybatisplus.generator.IDatabaseQuery$DefaultDatabaseQuery - 当前表[user]的主键为自增主键，会导致全局主键的ID类型设置失效!
14:20:22.182 [main] DEBUG com.baomidou.mybatisplus.generator.config.querys.MySqlQuery - 返回记录数:5,耗时(ms):14
14:20:22.502 [main] DEBUG com.baomidou.mybatisplus.generator.AutoGenerator - ==========================文件生成完成！！！==========================
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项目成功生成了Entity、Service、Controller、Mapper、Mapper.xml、DTO、VO文件。

User用户类

package com.shardingspherejdbc.mybatisplus.entity;
import com.baomidou.mybatisplus.annotation.FieldFill;

import com.baomidou.mybatisplus.annotation.IdType;

import com.baomidou.mybatisplus.annotation.TableField;

import com.baomidou.mybatisplus.annotation.TableId;

import com.baomidou.mybatisplus.annotation.TableName;

import io.swagger.annotations.ApiModel;

import io.swagger.annotations.ApiModelProperty;

import lombok.Getter;

import lombok.Setter;
import java.io.Serializable;

import java.util.Date;
/** * <p> * 用户 * </p> * * @author austin * @since 2023-02-09 */

@Getter

@Setter

@TableName(“user”)

@ApiModel(value = “User对象”, description = “用户”)

public class User implements Serializable {
<span class="hljs-keyword">private</span> static <span class="hljs-keyword">final</span> long serialVersionUID = <span class="hljs-number">1L</span>;

<span class="hljs-meta">@TableId(value = <span class="hljs-string">"id"</span>, type = IdType.AUTO)</span>
<span class="hljs-keyword">private</span> <span class="hljs-built_in">Long</span> id;

<span class="hljs-meta">@ApiModelProperty(<span class="hljs-string">"用户名"</span>)</span>
<span class="hljs-meta">@TableField(<span class="hljs-string">"username"</span>)</span>
<span class="hljs-keyword">private</span> String username;

<span class="hljs-meta">@ApiModelProperty(<span class="hljs-string">"手机号"</span>)</span>
<span class="hljs-meta">@TableField(<span class="hljs-string">"mobile"</span>)</span>
<span class="hljs-keyword">private</span> String mobile;

<span class="hljs-meta">@ApiModelProperty(<span class="hljs-string">"创建人"</span>)</span>
<span class="hljs-meta">@TableField(<span class="hljs-string">"create_by"</span>)</span>
<span class="hljs-keyword">private</span> String createBy;

<span class="hljs-meta">@ApiModelProperty(<span class="hljs-string">"创建时间"</span>)</span>
<span class="hljs-meta">@TableField(value = <span class="hljs-string">"create_time"</span>, fill = FieldFill.INSERT)</span>
<span class="hljs-keyword">private</span> Date createTime;

}

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想了解MyBatis Plus代码生成配置可以参考官方配置：代码生成器配置新

总结

对比Mybatis的Generator和MyBatis-Plus的AutoGenerator，就可以得出这样一条结论：后者的配置更简单，开发效率也更高，功能也更强大——可快速生成Mapper、Model、Service、Controller、DTO/VO层代码，到这里AutoGenerator生成器的介绍已经完成，文章如果对你有所帮助，欢迎点赞👍+关注❤+收藏✔，我是👨‍🎓austin流川枫，我们下期见!