作者：Orson

来源：cnblogs.com/java-class/p/6237564.html

IDEA 逆向 MyBatis 工程时，不像支持 Hibernate 那样有自带插件，需要集成第三方的 MyBatis Generator。

MyBatis Generator的详细介绍 http://mybatis.github.io/generator/index.html

本篇博客图解 MyBatis Generator 的使用过程，并结合实战说明逆向工程的使用方式。

搭建 MyBatis Generator 插件环境

a. 添加插件依赖 pom.xml

<plugin>     <groupId>org.mybatis.generatorgroupId>     <artifactId>mybatis-generator-maven-pluginartifactId>     <version>1.3.2version>     <configuration>        <configurationFile>src/main/resources/generatorConfig.xmlconfigurationFile>        <verbose>trueverbose>        <overwrite>trueoverwrite>     configuration>     <executions>        <execution>           <id>Generate MyBatis Artifactsid>        execution>     executions>     <dependencies>        <dependency>          <groupId>org.mybatis.generatorgroupId>          <artifactId>mybatis-generator-coreartifactId>          <version>1.3.2version>        dependency>     dependencies>plugin>

b.配置文件 generatorConfig.xml

xml version="1.0" encoding="UTF-8"?>br mpa-from-tpl="t"  />        PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd"><generatorConfiguration>    <properties resource="jdbc.properties"/>    <classPathEntry location="${jdbc_driverLocation}"/>

    <context id="default" targetRuntime="MyBatis3">

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

        <jdbcConnectiondriverClass="${jdbc_driverClass}"connectionURL="${jdbc_url}"userId="${jdbc_user}"password="${jdbc_pwd}">        jdbcConnection>

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

        <javaModelGenerator targetPackage="com.rambo.sdm.dao.pojo" targetProject="src/main/java">

            <property name="enableSubPackages" value="false"/>

            <property name="constructorBased" value="true"/>

            <property name="trimStrings" value="true"/>

            <property name="immutable" value="false"/>        javaModelGenerator>

        <sqlMapGenerator targetPackage="com.rambo.sdm.dao.mapper" targetProject="src/main/java">            <property name="enableSubPackages" value="false"/>        sqlMapGenerator>

        <javaClientGenerator targetPackage="com.rambo.sdm.dao.inter" targetProject="src/main/java" type="XMLMAPPER">            <property name="enableSubPackages" value="true"/>        javaClientGenerator>

        <table tableName="user" domainObjectName="UserPO">            <generatedKey column="uuid" sqlStatement="SELECT REPLACE(UUID(),'-','') UUID FROM DUAL"/>        table>    context>generatorConfiguration>

c.数据库配置文件 jdbc.properties

jdbc_driverLocation=D:\\Program Files\\Repository\\mysql\\mysql-connector-java\\5.1.38\\mysql-connector-java-5.1.38.jarjdbc_driverClass=com.mysql.jdbc.Driverjdbc_url=jdbc:mysql://localhost:3306/db_test?useUnicode=true&characterEncoding=utf-8jdbc_user=rootjdbc_pwd=123456validationQuery = select 1

d. 配置插件启动项

项目实战

User类就是普通的实体类，定义了数据库对应的字段，以及set/get方法。Mybatis 引入了 Example 类，用来封装数据库查询条件。

a.比如在一个项目 我们要删除某个小组下某个用户的信息

public int deleteUserApplyInfo(long user_id,long team_id){        StudyTeamUserApplyInfoExample ue = new StudyTeamUserApplyInfoExample();        ue.createCriteria().andUserIdEqualTo(new BigDecimal(user_id)).andTeamIdEqualTo(new BigDecimal(team_id));        return studyTeamUserApplyInfoDAO.deleteByExample(ue);}

b.根据小组ID(非主键 更新小组信息)

public int updateStudyTeamInfo(StudyTeamInfo st){        StudyTeamInfoExample ste = new StudyTeamInfoExample();        ste.createCriteria().andTeamIdEqualTo(st.getTeamId());        return studyTeamInfoDAO.updateByExampleSelective(st,ste);}

c.其它

(1)模糊查询并且排序

public List getStudyTeamInfoByName(String team_name){        StudyTeamInfoExample se = new StudyTeamInfoExample();        se.createCriteria().andTeamNameLike("%"+team_name+"%").andEnableEqualTo((short)1);        se.setOrderByClause("team_score desc");List ls = studyTeamInfoDAO.selectByExample(se);if(ls!=null&&ls.size()>0){return ls;        }return null;    }

(2)大于等于某个分数 并且小于某个分数的查询

public StudyTeamLevel getStudyTeamLevel(long score){        StudyTeamLevelExample le = new StudyTeamLevelExample();        le.createCriteria().andNeedScoreLessThanOrEqualTo(score).andUpScoreGreaterThan(score);        List ls = studyTeamLevelDAO.selectByExample(le);if(ls!=null&&ls.size()>0){return ls.get(0);        }return null;}

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