作者：Orson

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

• 1. 搭建 MyBatis Generator 插件環境
  • a. 添加插件依賴 pom.xml
  • b. 配置文件 generatorConfig.xml
  • c. 數據庫配置文件 jdbc.properties
  • d. 配置插件啟動項
• 2.項目實戰
  • a. 比如在一個項目 我們要刪除某個小組下某個用戶的信息
  • b. 根據小組ID(非主鍵 更新小組信息)
  • c. 各種查詢

IDEA 逆向 MyBatis 工程時，不像支持 Hibernate 那樣有自帶插件，需要集成第三方的 MyBatis Generator。

MyBatis Generator的詳細介紹 http://mybatis.github.io/generator/index.html

本篇博客圖解 MyBatis Generator 的使用過程，并結合實戰說明逆向工程的使用方式。

1. 搭建 MyBatis Generator 插件環境

a. 添加插件依賴 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"?>
generatorConfiguration
????????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. 數據庫配置文件 jdbc.properties

jdbc_driverLocation=D:\\Program Files\\Repository\\mysql\\mysql-connector-java\\5.1.38\\mysql-connector-java-5.1.38.jar
jdbc_driverClass=com.mysql.jdbc.Driver
jdbc_url=jdbc:mysql://localhost:3306/db_test?useUnicode=true&characterEncoding=utf-8
jdbc_user=root
jdbc_pwd=123456
validationQuery = select 1

d. 配置插件啟動項

2.項目實戰

User類就是普通的實體類，定義了數據庫對應的字段，以及set/get方法

Mybatis 引入了 Example 類，用來封裝數據庫查詢條件。

a. 比如在一個項目 我們要刪除某個小組下某個用戶的信息

????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. 根據小組ID(非主鍵 更新小組信息)

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

c. 各種查詢

(1)模糊查詢并且排序

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)大于等于某個分數 并且小于某個分數的查詢

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);

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