MyBatis Generator (MBG) 是一个Mybatis的代码生成器,可以自动生成一些简单的CRUD(插入,查询,更新,删除)操作代码,model代码,及mapper配置文件,只需要5步即可实现mybatis代码的自动生成。
- 添加数据库和mybatis相关依赖
- 引入mybatis-generator-maven插件
- 配置数据库连接
- 配置mybatis-generator代码生成策略
- 配置mybatis-generator运行方法
一、在pox.xml中添加依赖
<!-- mysql -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.35</version>
</dependency>
<!-- mybatis -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.0</version>
</dependency>
二、引入mybatis-generator插件
<plugin>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-maven-plugin</artifactId>
<version>1.3.6</version>
<configuration>
<verbose>true</verbose>
<overwrite>true</overwrite>
<configurationFile>src/main/resources/generatorConfig.xml</configurationFile>
</configuration>
<dependencies>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.35</version>
</dependency>
</dependencies>
<executions>
<execution>
<id>Generate MyBatis Artifacts</id>
<goals>
<goal>generate</goal>
</goals>
</execution>
</executions>
</plugin>
mybatis-generator
插件在使用时需要mysql-connector-java
驱动支持,在<configurationFile>
标签中指定generator配置文件路径,省缺时默认寻找src/main/resources/generatorConfig.xml
文件。
三、application-dev.properties配置数据库连接
spring.datasource.name=test
spring.datasource.url=jdbc:mysql://127.0.0.1:3306/test
spring.datasource.username=root
spring.datasource.password=test123
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
四、generator代码自动生成策略
<?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>
<!-- 导入配置文件 -->
<properties resource="application-dev.properties"/>
<!-- defaultModelType="flat" 设置复合主键时不单独为主键创建实体 -->
<context id="MySql" defaultModelType="flat" targetRuntime="MyBatis3Simple">
<!-- 生成的POJO实现java.io.Serializable接口 -->
<plugin type="org.mybatis.generator.plugins.SerializablePlugin" />
<!--注释-->
<commentGenerator>
<!-- 是否去除自动生成的注释 true:是 : false:否 -->
<property name="suppressAllComments" value="true"/>
<!-- 将数据库中表的字段描述信息添加到注释 -->
<property name="addRemarkComments" value="true"/>
<!-- 注释里不添加日期 -->
<property name="suppressDate" value="true"/>
</commentGenerator>
<!-- 数据库连接,直接通过${}读取application.properties里的配置 -->
<jdbcConnection
driverClass="${spring.datasource.driver-class-name}"
connectionURL="${spring.datasource.url}"
userId="${spring.datasource.username}"
password="${spring.datasource.password}"/>
<javaTypeResolver>
<property name="forceBigDecimals" value="false"/>
</javaTypeResolver>
<!-- 生成POJO对象,并将类放到com.songguoliang.springboot.entity包下 -->
<javaModelGenerator targetPackage="com.soft.springboot.entity" targetProject="src/main/java">
<property name="enableSubPackages" value="true"/>
<property name="trimStrings" value="true"/>
</javaModelGenerator>
<!-- 生成mapper xml文件,并放到resources下的mapper文件夹下 -->
<sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources">
<property name="enableSubPackages" value="true"/>
</sqlMapGenerator>
<!-- 生成mapper xml对应dao接口,放到com.songguoliang.springboot.mapper包下-->
<javaClientGenerator targetPackage="com.soft.springboot.mapper" targetProject="src/main/java" type="XMLMAPPER">
<property name="enableSubPackages" value="true"/>
</javaClientGenerator>
<!-- table标签可以有多个,至少一个,tableName指定表名,可以使用_和%通配符 -->
<table tableName="user" domainObjectName="User" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false">
<!-- 是否只生成POJO对象 -->
<property name="modelOnly" value="false"/>
<!-- 数据库中表名有时我们都会带个前缀,而实体又不想带前缀,这个配置可以把实体的前缀去掉 -->
<domainObjectRenamingRule searchString="^Tbl" replaceString=""/>
</table>
</context>
</generatorConfiguration>
在配置文件中需要配置数据库连接,还要指定自动生成后存放pojo对象、mapper xml文件、dao接口的文件路径,并且指定数据库中需要自动生成文件的表名,tableName
属性可以使用通配符,为了修改方便,我们引用配置文件application-dev.properties
,读取配置文件中的数据库配置,需要注意的是:generator配置文件中至少要配置一个<table>
,MyBatis3Simple 这是默认值不会有"by example"一类的方法,只有少量的动态SQL。flat该模型为每一张表只生成一个实体类。这个实体类包含表中的所有字段。
五、运行mybatis-generator插件生成代码
直接运行即可
六、完整的pox.xml文件
<?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>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.3.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.soft.springboot</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</name>
<description>Demo project for Spring Boot</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.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<!-- mysql -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.35</version>
</dependency>
<!-- mybatis -->
<dependency>
<groupId>org.mybatis.spring.boot</groupId>
<artifactId>mybatis-spring-boot-starter</artifactId>
<version>1.3.0</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
<!-- mybatis代码自动生成插件 -->
<plugin>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-maven-plugin</artifactId>
<version>1.3.6</version>
<configuration>
<verbose>true</verbose>
<overwrite>true</overwrite>
<configurationFile>src/main/resources/generatorConfig.xml</configurationFile>
</configuration>
<dependencies>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.35</version>
</dependency>
</dependencies>
<executions>
<execution>
<id>Generate MyBatis Artifacts</id>
<goals>
<goal>generate</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>