11_逆向工程

痛定思痛。 2023-09-27 15:03 54阅读 0赞

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

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<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>

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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>

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![137e884c9d0ceb23bec5823069cab8fe.gif][]

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

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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();
            }
        }
    }

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生成的实体类和Mapper接口和Mapper映射文件,包含了基本的CURD功能,哪里需要文件就放哪里

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[2eb6bb8105b8bb96cfed6d6bfcd4e662.gif]: https://img-blog.csdnimg.cn/img_convert/2eb6bb8105b8bb96cfed6d6bfcd4e662.gif
[137e884c9d0ceb23bec5823069cab8fe.gif]: https://img-blog.csdnimg.cn/img_convert/137e884c9d0ceb23bec5823069cab8fe.gif
[409f511aeb4971ce86301974452f86ef.gif]: https://img-blog.csdnimg.cn/img_convert/409f511aeb4971ce86301974452f86ef.gif
[cd8406e6c83b05d5f8eef7de17202a49.gif]: https://img-blog.csdnimg.cn/img_convert/cd8406e6c83b05d5f8eef7de17202a49.gif
[061be0d0b10be2d9ea28dd3417e0730a.gif]: https://img-blog.csdnimg.cn/img_convert/061be0d0b10be2d9ea28dd3417e0730a.gif
[f94e3019af6559b2e26f185726bae9b4.gif]: https://img-blog.csdnimg.cn/img_convert/f94e3019af6559b2e26f185726bae9b4.gif
[db345bf1ae019fc9de7d3c10f62bfada.png]: https://img-blog.csdnimg.cn/img_convert/db345bf1ae019fc9de7d3c10f62bfada.png