一分钟带你学会利用mybatis-generator自动生成代码！

怼烎@ 2023-02-14 10:19 2阅读 0赞

> 之前的文章 [《SpringBoot系列-整合Mybatis（XML配置方式）》][SpringBoot_-_Mybatis_XML]介绍了XML配置方式整合的过程，本文介绍下利用Mybatis-generator生成xml、dao、entity的过程。

### 一、MyBatis Generator简介 ###

MyBatis Generator是MyBatis官方提供的代码生成器，可以生成xml、dao、entity。

官网介绍见：[http://mybatis.org/generator/][http_mybatis.org_generator]

### 二、使用方式 ###

MyBatis Generator的使用方式有4种：

*  命令行生成

*  Maven方式生成

*  使用Ant任务生成

*  使用Java代码生成

本文将使用Intel IDEA+Maven方式生成代码，因为集成和使用比较简单，配置完成后直接双击运行即可。

### 三、实战 ###

首先新建一个SpringBoot项目spring-mybatis-generator，然后按照下面步骤操作。

1.  pom.xml中配置plugin

<plugin>
        <groupId>org.mybatis.generator</groupId>
        <artifactId>mybatis-generator-maven-plugin</artifactId>
        <version>1.3.2</version>
        <configuration>
            
            <configurationFile>src/main/resources/mybatis-generator.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>
        </dependencies>
    </plugin>

1.  修改mybatis-generator.xml文件

上一步pom.xml中指定了一个配置文件，所以在resources目录下新建mybatis-generator.xml，MyBatis Generator通过这个配置文件才可以进行如下操作：

*  如何连接到数据库

*  生成什么对象，以及如何生成它们

*  哪些表应用于对象生成

完整内容下面会有，需要注意的是。

> JDBC驱动jar的路径一定要写绝对路径。  
> JDBC驱动jar的路径一定要写绝对路径。  
> JDBC驱动jar的路径一定要写绝对路径。  
>

重要的事情说3遍。

mybatis-generator.xml完整内容如下：

<?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>
    
        
        
        
        <classPathEntry location="C:\Users\java_suisui\.m2\repository\mysql\mysql-connector-java\5.1.39\mysql-connector-java-5.1.39.jar"/>
    
        
        <context id="Mysql" targetRuntime="MyBatis3Simple" defaultModelType="flat">
            <property name="autoDelimitKeywords" value="true" />
            <property name="beginningDelimiter" value="`" />
            <property name="endingDelimiter" value="`" />
            <property name="javaFileEncoding" value="utf-8" />
            <plugin type="org.mybatis.generator.plugins.SerializablePlugin" />
    
            <plugin type="org.mybatis.generator.plugins.ToStringPlugin" />
    
            
            <commentGenerator >
                <property name="suppressAllComments" value="true"/>
                <property name="suppressDate" value="true" /> 
            </commentGenerator>
    
            
            <jdbcConnection driverClass="com.mysql.jdbc.Driver"
                            connectionURL="jdbc:mysql://localhost:3306/demo"
                            userId="root"
                            password="123456">
            </jdbcConnection>
    
            
            <javaTypeResolver>
                
                <property name="forceBigDecimals" value="false"/>
            </javaTypeResolver>
    
            
            <javaModelGenerator targetPackage="com.example.springbootmybatis.generator.entity" targetProject="src/main/java">
                <property name="enableSubPackages" value="true"/>
                <property name="trimStrings" value="true"/>
            </javaModelGenerator>
    
            
            <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources" >
                <property name="enableSubPackages" value="false" />
            </sqlMapGenerator>
    
            
            <javaClientGenerator targetPackage="com.example.springbootmybatis.generator.dao" targetProject="src/main/java" type="XMLMAPPER" >
                <property name="enableSubPackages" value="false" />
            </javaClientGenerator>
    
            <table tableName="user" enableCountByExample="true" enableUpdateByExample="true" enableDeleteByExample="true" enableSelectByExample="true" selectByExampleQueryId="true">
                <generatedKey column="id" sqlStatement="Mysql" identity="true" />
            </table>
    
            <table tableName="user_role" enableCountByExample="true" enableUpdateByExample="true" enableDeleteByExample="true" enableSelectByExample="true" selectByExampleQueryId="true">
                <generatedKey column="id" sqlStatement="Mysql" identity="true" />
            </table>
    
        </context>
    </generatorConfiguration>

1.  生成代码

点击IntelIDEA右侧的“Maven Projects”，找到spring-boot-mybatis-generator下面的mybatis-generator:generate，双击运行，日志中出现“BUILD SUCCESS”说明代码已生成。

**运行截图：**

![format_png][]

**生成代码截图：**

![format_png 1][]

**运行日志：**

[INFO] Scanning for projects...
    [INFO]                                                                         
    [INFO] ------------------------------------------------------------------------
    [INFO] Building spring-boot-mybatis-generator 0.0.1-SNAPSHOT
    [INFO] ------------------------------------------------------------------------
    [INFO] 
    [INFO] --- mybatis-generator-maven-plugin:1.3.2:generate (default-cli) @ spring-mybatis-generator ---
    [INFO] Connecting to the Database
    [INFO] Introspecting table user
    log4j:WARN No appenders could be found for logger (org.mybatis.generator.internal.db.DatabaseIntrospector).
    log4j:WARN Please initialize the log4j system properly.
    log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
    [INFO] Introspecting table user_role
    [INFO] Generating Record class for table user
    [INFO] Generating Mapper Interface for table user
    [INFO] Generating SQL Map for table user
    [INFO] Generating Record class for table user_role
    [INFO] Generating Mapper Interface for table user_role
    [INFO] Generating SQL Map for table user_role
    [INFO] Saving file UserMapper.xml
    [INFO] Saving file UserRoleMapper.xml
    [INFO] Saving file User.java
    [INFO] Saving file UserMapper.java
    [INFO] Saving file UserRole.java
    [INFO] Saving file UserRoleMapper.java
    [INFO] ------------------------------------------------------------------------
    [INFO] BUILD SUCCESS
    [INFO] ------------------------------------------------------------------------

到此利用mybatis-generator自动生成代码已经全部介绍完成了，有问题欢迎留言沟通哦！

完整源码地址： [https://github.com/suisui2019/springboot-study][https_github.com_suisui2019_springboot-study]

**推荐阅读**[1.手把手带你实战下Spring的七种事务传播行为][1._Spring]

[2.SpringBoot系列-整合Mybatis（注解方式）][2.SpringBoot_-_Mybatis]

[3.SpringBoot系列-整合Mybatis（XML配置方式）][SpringBoot_-_Mybatis_XML]

[4.Java中打印日志，这4点很重要！][4.Java_4]

[5.SpringBoot集成JWT实现权限认证][5.SpringBoot_JWT]

[SpringBoot_-_Mybatis_XML]: https://link.zhihu.com/?target=https%3A//mp.weixin.qq.com/s/Ad8aKvyTgjFlzjOcadO1xQ
[http_mybatis.org_generator]: https://link.zhihu.com/?target=http%3A//mybatis.org/generator/
[format_png]: https://imgconvert.csdnimg.cn/aHR0cHM6Ly9waWMyLnpoaW1nLmNvbS84MC92Mi0yMjJmN2IyZDZkMGJmYjU0ODZiNzdmZjY1Y2YwMTFmNV83MjB3LmpwZw?x-oss-process=image/format,png
[format_png 1]: https://imgconvert.csdnimg.cn/aHR0cHM6Ly9waWMyLnpoaW1nLmNvbS84MC92Mi0yNzMyZDFjNGMyZWJjNTRlNmU1ZjdlZTA5OGQzZDY4MV83MjB3LmpwZw?x-oss-process=image/format,png
[https_github.com_suisui2019_springboot-study]: https://link.zhihu.com/?target=https%3A//github.com/suisui2019/springboot-study
[1._Spring]: https://link.zhihu.com/?target=https%3A//mp.weixin.qq.com/s/g_fCo8rFGtWseVoKWahaIQ
[2.SpringBoot_-_Mybatis]: https://link.zhihu.com/?target=https%3A//mp.weixin.qq.com/s/toH_rCF5Sf3sPK-NPp5OhQ
[4.Java_4]: https://link.zhihu.com/?target=https%3A//mp.weixin.qq.com/s/Y1S_SogYOpY-oxF0KXNZig
[5.SpringBoot_JWT]: https://link.zhihu.com/?target=https%3A//mp.weixin.qq.com/s/49JC9pgdfWYd7P2a53wA_g