11_逆向工程

news2024/11/26 0:43:54

MyBatis的一个主要的特点就是需要程序员自己编写SQL，那么如果表太多的话，难免会很麻烦，所以MyBatis官方提供了一个逆向工程，可以针对单表自动生成MyBatis执行所需要的代码（包括mapper.xml，mapper.java，pojo）。一般在开发中，常用的逆向工程方式是通过数据库的表生成代码。

创建maven项目导入逆向工程依赖

<dependencies>


<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.16</version>
</dependency>

<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.6.1</version>
</dependency>

<dependency>
<groupId>org.mybatis.generator</groupId>
<artifactId>mybatis-generator-core</artifactId>
<version>1.3.2</version>
</dependency>
</dependencies>

配置逆向工程配置文件在resources目录下放置一个名为generatorConfig.xml的配置文件,文件内容如下

<?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="testTables" targetRuntime="MyBatis3">
<commentGenerator>

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


<jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
connectionURL="jdbc:mysql://127.0.0.1:3306/mydb?useSSL=false&useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai&allowPublicKeyRetrieval=true"
userId="root"
password="root">
</jdbcConnection>

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

<javaModelGenerator targetPackage="com.msb.pojo"
targetProject=".\src">

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

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

<sqlMapGenerator targetPackage="com.msb.mapper"
targetProject=".\src">

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

<javaClientGenerator type="XMLMAPPER"
targetPackage="com.msb.mapper"
targetProject=".\src">

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


<table tableName="dept" domainObjectName="Dept"
enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false"
enableSelectByExample="false" selectByExampleQueryId="false" >
<columnOverride column="id" javaType="Integer" />
</table>

</context>
</generatorConfiguration>

在resources目录下放置一个名为log4j.properties的配置文件,文件内容如下

log4j.rootLogger=debug,stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.err
log4j.appender.stdout.layout=org.apache.log4j.SimpleLayout
log4j.appender.logfile=org.apache.log4j.FileAppender
log4j.appender.logfile.File=d:/msb.log
log4j.appender.logfile.layout=org.apache.log4j.PatternLayout
log4j.appender.logfile.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %l %F %p %m%n

运行逆向工程代码

package com.msb.gennerator;
import org.mybatis.generator.api.MyBatisGenerator;
import org.mybatis.generator.config.Configuration;
import org.mybatis.generator.config.xml.ConfigurationParser;
import org.mybatis.generator.internal.DefaultShellCallback;
import java.io.File;
import java.util.ArrayList;
import java.util.List;
/**
*
*/
public class GeneratorSqlmap {
public void generator() throws Exception{
List<String> warnings = new ArrayList<String>();
boolean overwrite = true;
File configFile = new File("D:\\ideaProjects\\reverse\\target\\classes\\generatorConfig.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);
}
public static void main(String[] args) throws Exception {
try {
GeneratorSqlmap generatorSqlmap = new GeneratorSqlmap();
generatorSqlmap.generator();
} catch (Exception e) {
e.printStackTrace();
}
}
}