使用Mybatis逆向工程(generator)的意義分別有哪些?
- 可以幫助我們將表中字段封裝到實體類中
- 可以幫助我們生成實體映射文件
- 可以幫助我們生成實體接口類
使用Mybatis逆向工程(generator)步驟:
第一步:在pom.xml文件中引入MyBatis generator的依賴包
第二步:根據官方文檔提示創建一個全局的配置文件mbg.xml
第三步:執行生成
開始項目結構示意圖,如下:
第一步我們既然要使用Mybatis逆向工程(generator),那我們就得去下載mybatis generator的包,實例圖如下:
以前都是下載包然後把包構建到項目中去,現在我們使用了maven,說以我們不用去下載了,直接複製包的地址,然後在pom文件中進行配置,配置完成,maven會自動幫助我們下載指定包,配置pom文件代碼如下:
pom.xml
<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>
<groupId>com.anzhuo.cm</groupId>
<artifactId>SSM_studentInfoManager</artifactId>
<version>0.0.1-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.8.8</version>
</dependency>
<dependency>
<groupId>com.github.pagehelper</groupId>
<artifactId>pagehelper</artifactId>
<version>5.0.0</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>4.3.7.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>4.3.7.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>4.3.7.RELEASE</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aspects</artifactId>
<version>4.3.7.RELEASE</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis</artifactId>
<version>3.4.5</version>
</dependency>
<dependency>
<groupId>org.mybatis</groupId>
<artifactId>mybatis-spring</artifactId>
<version>1.3.0</version>
</dependency>
<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.1.1</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.41</version>
</dependency>
<dependency>
<groupId>jstl</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.0.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-core</artifactId>
<version>1.3.5</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>5.4.1.Final</version>
</dependency>
<!--這以下的是加載到mybatis generator的jar包-->
<dependency>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-core</artifactId>
<version>1.3.5</version>
</dependency>
</dependencies>
</project>
第三步:既然我們都以經把包的部分整好了,那我們現在該去根據文檔來配置我們的mbg.xml配置文件了,首先我們得先有這個mbg的文件,在項目》》》右擊》》》新建》》》other》》》xml》》》給文件命名爲mbg.xml》》》完成
示例圖如下:
創建好了之後我們就就可以去查看官方文檔了,根據官方文檔來編寫mbg.xml配置文件,那我們現在來看下官方文檔,示例圖如下:
找到了怎麼配置mbg文件之後我們將它全部複製,粘貼到我們的mbg文件中去,那麼,我們需要修改寫什麼呢,修改如下:
修改前:
mbg.xml
<?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>
<classPathEntry location="/Program Files/IBM/SQLLIB/java/db2java.zip" />
<context id="DB2Tables" targetRuntime="MyBatis3">
<jdbcConnection driverClass="COM.ibm.db2.jdbc.app.DB2Driver"
connectionURL="jdbc:db2:TEST"
userId="db2admin"
password="db2admin">
</jdbcConnection>
<javaTypeResolver >
<property name="forceBigDecimals" value="false" />
</javaTypeResolver>
<javaModelGenerator targetPackage="test.model" targetProject="\MBGTestProject\src">
<property name="enableSubPackages" value="true" />
<property name="trimStrings" value="true" />
</javaModelGenerator>
<sqlMapGenerator targetPackage="test.xml" targetProject="\MBGTestProject\src">
<property name="enableSubPackages" value="true" />
</sqlMapGenerator>
<javaClientGenerator type="XMLMAPPER" targetPackage="test.dao" targetProject="\MBGTestProject\src">
<property name="enableSubPackages" value="true" />
</javaClientGenerator>
<table schema="DB2ADMIN" tableName="ALLTYPES" domainObjectName="Customer" >
<property name="useActualColumnNames" value="true"/>
<generatedKey column="ID" sqlStatement="DB2" identity="true" />
<columnOverride column="DATE_FIELD" property="startDate" />
<ignoreColumn column="FRED" />
<columnOverride column="LONG_VARCHAR_FIELD" jdbcType="VARCHAR" />
</table>
</context>
</generatorConfiguration>
修改後:
mbg.xml
<?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="DB2Tables" targetRuntime="MyBatis3">
<!-- 去除生成代碼中的註釋 -->
<commentGenerator>
<property name="suppressAllComments" value="true"/>
</commentGenerator>
<!-- 配置數據源 -->
<jdbcConnection driverClass="com.mysql.jdbc.Driver"
connectionURL="jdbc:mysql://localhost:3306/studentinfomanager"
userId="root"
password="123">
</jdbcConnection>
<javaTypeResolver >
<property name="forceBigDecimals" value="false" />
</javaTypeResolver>
<!-- 配置生成的實體類放在哪個包下面 -->
<javaModelGenerator targetPackage="com.anzhuo.cm.pojo" targetProject=".\src\main\java">
<property name="enableSubPackages" value="true" />
<property name="trimStrings" value="true" />
</javaModelGenerator>
<!-- 配置生成的實體映射文件放在哪個文件夾下面 -->
<sqlMapGenerator targetPackage="mapper" targetProject=".\src\main\resources">
<property name="enableSubPackages" value="true" />
</sqlMapGenerator>
<!-- 配置生成的接口放在哪個包下面 -->
<javaClientGenerator type="XMLMAPPER" targetPackage="com.anzhuo.cm.dao" targetProject=".\src\main\java">
<property name="enableSubPackages" value="true" />
</javaClientGenerator>
<!-- 配置所有數據庫中的表,將要生成的實體類名 -->
<table schema="DB2ADMIN" tableName="s_aattendance" domainObjectName="Saattendance" >
</table>
<table schema="DB2ADMIN" tableName="s_badbehavior" domainObjectName="Sbadbehavior" >
</table>
<table schema="DB2ADMIN" tableName="s_basicmessage" domainObjectName="Sbasicmessage" >
</table>
<table schema="DB2ADMIN" tableName="s_charge" domainObjectName="Scharge" >
</table>
<table schema="DB2ADMIN" tableName="s_charge_launch" domainObjectName="Scharge_launch" >
</table>
<table schema="DB2ADMIN" tableName="s_class" domainObjectName="Sclass" >
</table>
<table schema="DB2ADMIN" tableName="s_honour" domainObjectName="Shonour" >
</table>
<table schema="DB2ADMIN" tableName="s_login" domainObjectName="Slogin" >
</table>
<table schema="DB2ADMIN" tableName="s_performance" domainObjectName="Sperformance" >
</table>
<table schema="DB2ADMIN" tableName="s_profession" domainObjectName="Srofession" >
</table>
<table schema="DB2ADMIN" tableName="s_reg" domainObjectName="Sreg" >
</table>
<table schema="DB2ADMIN" tableName="s_work" domainObjectName="Swork" >
</table>
</context>
</generatorConfiguration>
第三步:根據官方文檔遍寫執行生成代碼,首先需要有個執行生成的類,在src/test/resource下新建一個Testmbg.java文件,結構如下:
然後把複製的代碼,粘貼到自己的Testmbg.java中,示例如下:
Testmbg.java
package com.anzhuo.cm.test;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.mybatis.generator.api.MyBatisGenerator;
import org.mybatis.generator.config.Configuration;
import org.mybatis.generator.config.xml.ConfigurationParser;
import org.mybatis.generator.exception.XMLParserException;
import org.mybatis.generator.internal.DefaultShellCallback;
public class Testmbg {
public static void main(String[] args) throws Exception{
List<String> warnings = new ArrayList<String>();
boolean overwrite = true;
/* 加載你的mbg配置文件*/
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);
myBatisGenerator.generate(null);
System.out.println("ojbk");
}
}
當你運行成時,你在刷新一下你的項目,就可以看到你生成的東西啦
開始項目結構示意圖,如下: