Mybatis Generator是一个mybatis工具项目,用于生成mybatis的model,mapper,dao持久层代码。Mybatis Generator提供了maven plugin,ant targetjava三种方式启动。现在主流的构建工具是gradle,虽然mybatis generator没有提供gradle的插件,但gradle可以调用ant任务,因此,gradle也能启动Mybatis Generator。

环境说明

  • 数据库:mysql
  • 数据库配置文件:src/main/resources/db-mysql.properties
  • 项目中使用了mybatistk.mybatis:mapper:3.3.2插件

配置依赖

build.gradle中:
运行ant需要运行环境,也就是相应的jar包,因此添加一个配置

configurations {

mybatisGenerator
}

给这个配置添加依赖

repositories {
mavenCentral()
}
dependencies {
mybatisGenerator 'org.mybatis.generator:mybatis-generator-core:1.3.2'
mybatisGenerator 'mysql:mysql-connector-java:5.1.36'
mybatisGenerator 'tk.mybatis:mapper:3.3.2'
}

配置task

build.gradle中,定义一个task,在task里面调用ant


def getDbProperties = {
def properties = new Properties()
file("src/main/resources/db-mysql.properties").withInputStream { inputStream ->
properties.load(inputStream)
}

properties;

}


task mybatisGenerate << {


def properties = getDbProperties()



ant.properties['targetProject'] = projectDir.path
ant.properties['driverClass'] = properties.getProperty("jdbc.driverClassName")
ant.properties['connectionURL'] = properties.getProperty("jdbc.url")
ant.properties['userId'] = properties.getProperty("jdbc.user")
ant.properties['password'] = properties.getProperty("jdbc.pass")
ant.properties['src_main_java'] = sourceSets.main.java.srcDirs[0].path
ant.properties['src_main_resources'] = sourceSets.main.resources.srcDirs[0].path
ant.properties['modelPackage'] = this.modelPackage
ant.properties['mapperPackage'] = this.mapperPackage
ant.properties['sqlMapperPackage'] = this.sqlMapperPackage

ant.taskdef(
name: 'mbgenerator',
classname: 'org.mybatis.generator.ant.GeneratorAntTask',
classpath: configurations.mybatisGenerator.asPath
)
ant.mbgenerator(overwrite: true,
configfile: 'db/generatorConfig.xml', verbose: true) {
propertyset {
propertyref(name: 'targetProject')
propertyref(name: 'userId')
propertyref(name: 'driverClass')
propertyref(name: 'connectionURL')
propertyref(name: 'password')
propertyref(name: 'src_main_java')
propertyref(name: 'src_main_resources')
propertyref(name: 'modelPackage')
propertyref(name: 'mapperPackage')
propertyref(name: 'sqlMapperPackage')

}
}
}

大致思路是:

  • db-mysql.propertis读取配置
  • 把配置注入ant任务
  • 运行ant,生成文件

数据库配置文件,文件在src/main/resources/db-mysql.properties

jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost/mhml
jdbc.user=root
jdbc.pass=rootpass

其他配置,gradle.propertis

modelPackage=com.dreamliner.mhml.entity
#生成的mapper接口类所在包
mapperPackage=com.dreamliner.mhml.mapper
#生成的mapper xml文件所在包,默认存储在resources目录下
sqlMapperPackage=mybatis_mapper

db/generatorConfig配置

db/generatorConfig.xml文件用于配置生成策略,官网详细介绍

<?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>
<context id="Mysql" targetRuntime="MyBatis3Simple" defaultModelType="flat">


<plugin type="tk.mybatis.mapper.generator.MapperPlugin">
<property name="mappers" value="tk.mybatis.mapper.common.Mapper"/>
<!-- caseSensitive默认false,当数据库表名区分大小写时,可以将该属性设置为true -->
<property name="caseSensitive" value="true"/>
</plugin>


<commentGenerator>
<property name="suppressAllComments" value="true"/>
</commentGenerator>

<jdbcConnection driverClass="${driverClass}"
connectionURL="${connectionURL}"
userId="${userId}"
password="${password}">
</jdbcConnection>


<javaModelGenerator targetPackage="${modelPackage}" targetProject="${src_main_java}"/>

<sqlMapGenerator targetPackage="${sqlMapperPackage}" targetProject="${src_main_resources}"/>

<javaClientGenerator targetPackage="${mapperPackage}" targetProject="${src_main_java}" type="XMLMAPPER"/>
<!-- sql占位符,表示所有的表 -->
<table tableName="%">
<generatedKey column="epa_id" sqlStatement="Mysql" identity="true" />
</table>

</context>
</generatorConfiguration>

run,生成代码

gradle  mybatisGenerate