【串线篇】Mybatis拓展之MBG

MBG-逆向工程

一、介绍

MBG：MyBatis Generator：代码生成器；

MyBatis官方提供的代码生成器；帮我们逆向生成；

正向：

table----javaBean---BookDao---dao.xml---xxx

逆向工程：

根据数据表table，逆向分析数据表，自动生成javaBean---BookDao---dao.xml---xxx

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二、配置

1、导包：mbg的核心包

….. mybatis-generator-core-1.3.2.jar

2、编写mbg.xml配置文件

<?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>

    <!--
    MyBatis3Simple：基础班CRUD
    MyBatis3：复杂版CRUD
     -->
    <context id="DB2Tables" targetRuntime="MyBatis3">
        <commentGenerator>
            <property name="suppressAllComments" value="true"/>
        </commentGenerator>
        <!-- jdbcConnection:指导连接到哪个数据库 -->
        <jdbcConnection

            driverClass="com.mysql.jdbc.Driver"
            connectionURL="jdbc:mysql://localhost:3306/mybatis_0325"

            userId="root"

            password="123456">
        </jdbcConnection>

        <javaTypeResolver>
            <property name="forceBigDecimals" value="false" />
        </javaTypeResolver>

        <!-- javaModelGenerator：生成pojo

        targetPackage：生成的pojo放在哪个包
        targetProject：放在哪个工程下
        -->
        <javaModelGenerator targetPackage="com.atguigu.bean"
            targetProject=".\src">
            <property name="enableSubPackages" value="true" />
            <property name="trimStrings" value="true" />
        </javaModelGenerator>

        <!--sqlMapGenerator：sql映射文件生成器；指定xml生成的地方  -->
        <sqlMapGenerator targetPackage="com.atguigu.dao"
            targetProject=".\conf">
            <property name="enableSubPackages" value="true" />
        </sqlMapGenerator>

        <!-- javaClientGenerator：dao接口生成的地方 -->
        <javaClientGenerator type="XMLMAPPER"
            targetPackage="com.atguigu.dao"

            targetProject=".\src">
            <property name="enableSubPackages" value="true" />
        </javaClientGenerator>

        <!-- table：指定要逆向生成哪个数据表
        tableName="t_cat"：表名
        domainObjectName=""：这个表对应的对象名
         -->
        <table tableName="t_cat" domainObjectName="Cat"></table>
        <table tableName="t_employee" domainObjectName="Employee"></table>
        <table tableName="t_teacher" domainObjectName="Teacher"></table>

    </context>
</generatorConfiguration>

三、测试

public class MBGTest {

    public static void main(String[] args) throws Exception {
        List<String> warnings = new ArrayList<String>();
        boolean overwrite = true;
        File configFile = new File("mbg.xml");
        ConfigurationParser cp = new ConfigurationParser(warnings);
        Configuration config = cp.parseConfiguration(configFile);
        DefaultShellCallback callback = new DefaultShellCallback(overwrite);
        MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config,
                callback, warnings);
        //代码生成
        myBatisGenerator.generate(null);
        System.out.println("生成ok了！");
    }

}