Mybatis逆向工程

1、什么是Mybatis逆向工程

  • 简单的理解,MyBatis逆向工程,就是使用相应插件,然后根据你数据库表的设计,自动生成MyBatis数据库连接的一些文件。
  • 自动生成的文件有实体类pojo,实现业务逻辑的接口mapper/dao,操作数据库表所需的映射文件*mapper.xml。
  • 在实际的开发过程中,大大减轻了手动编写实体,接口和实现接口的SQL语句的压力。

Mybatis逆向工程_sql

2、添加依赖pop.xml

<dependencies>
    <!--mybatis逆向工程-->
    <dependency>
        <groupId>org.mybatis.generator</groupId>
        <artifactId>mybatis-generator-core</artifactId>
        <version>1.3.7</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.21</version>
    </dependency>
</dependencies>

<build>
    <plugins>
        <!-- mybatis逆向工程插件 -->
        <plugin>
            <groupId>org.mybatis.generator</groupId>
            <artifactId>mybatis-generator-maven-plugin</artifactId>
            <version>1.3.7</version>
            <dependencies>
                <dependency>
                    <groupId>mysql</groupId>
                    <artifactId>mysql-connector-java</artifactId>
                    <version>8.0.21</version>
                </dependency>
            </dependencies>
            <configuration>
                <!--配置文件的路径-->
                <configurationFile>src/main/resources/generator/generatorConfig.xml</configurationFile>
                <overwrite>true</overwrite>
            </configuration>
        </plugin>
    </plugins>

    <resources>
        <resource>
            <includes>
                <include>**/*.*</include>
            </includes>
            <directory>src/main/resources</directory>
        </resource>
    </resources>
</build>

3、generatorConfig.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>
    <!--指定了驱动jar包的位置,这个是针对下载Jar包的方式,因为用了maven所以这个就用不上了-->
    <!-- <classPathEntry location="D:/mvn_repository_new/mysql/mysql-connector-java/5.1.45/mysql-connector-java-5.1.45.jar"/>-->

    <context id="DB2Tables" targetRuntime="MyBatis3">
        <commentGenerator>
            <property name="suppressDate" value="false"/>
            <!-- 是否去除自动生成的注释 true:是 : false:否 -->
            <property name="suppressAllComments" value="true"/>
        </commentGenerator>

        <!--数据库链接URL,用户名、密码 -->
        <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
                        connectionURL="jdbc:mysql://localhost:3306/online?useSSL=false&amp;serverTimezone=Asia/Shanghai&amp;allowPublicKeyRetrieval=true"
                        userId="root"
                        password="mc123456">
        </jdbcConnection>
        <!--指定生成entity实体类的具体位置-->
        <javaModelGenerator targetPackage="com.mc.entity" targetProject="./src/main/java">
            <property name="enableSubPackages" value="true"/>
            <property name="trimStrings" value="true"/>
        </javaModelGenerator>
        <!--指定生成mybatis映射xml文件的包名和位置-->
        <sqlMapGenerator targetPackage="mapper" targetProject="./src/main/resources">
            <property name="enableSubPackages" value="true"/>
        </sqlMapGenerator>
        <!--指定生成mapper接口的具体位置-->
        <javaClientGenerator targetPackage="com.mc.mapper" targetProject="./src/main/java" type="XMLMAPPER">
            <property name="enableSubPackages" value="true"/>
        </javaClientGenerator>

        <!--要生成entity/mapper的表名及自定义的DO名-->
        <!--<table tableName="users" domainObjectName="User"/>-->

        <!--<table tableName="product_brand" domainObjectName="ProductBrand" />-->

        <!--mybatis generator代码生成器在默认的情况下会生成对于表实体类的一个Examle类, 可以更改生成器的配置可避免生成Examle类,
        enableCountByExample,enableUpdateByExample,enableDeleteByExample,enableSelectByExample等配置为false后, 就不会生成生成Examle类了 -->

        <table tableName="t_bis_wallet" enableCountByExample="false" enableUpdateByExample="false"
               enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"/>
       
    <!--或者直接写表名-->
	<!--<table schema="" tableName="product_type"></table>-->

    </context>
</generatorConfiguration>

4、启动程序

package com.mybatisTools;

import java.io.File;
import java.util.ArrayList;
import java.util.List;
import org.mybatis.generator.api.MyBatisGenerator;
import org.mybatis.generator.api.ProgressCallback;
import org.mybatis.generator.config.Configuration;
import org.mybatis.generator.config.xml.ConfigurationParser;
import org.mybatis.generator.internal.DefaultShellCallback;

public class GeneratorSqlmap {
    public GeneratorSqlmap() {
    }

    public void generator() throws Exception {
        List<String> warnings = new ArrayList();
        boolean overwrite = true;
        File configFile = new File("src/main/resources/generator/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((ProgressCallback)null);
    }

    public static void main(String[] args) throws Exception {
        try {
            GeneratorSqlmap generatorSqlmap = new GeneratorSqlmap();
            generatorSqlmap.generator();
        } catch (Exception var2) {
            var2.printStackTrace();
        }

    }
}