mybatis的逆向工程（generate）

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一、添加依赖与插件

  在maven工程中的pom.xml文件中：

<dependencies>
	<dependency>
		<groupId>org.mybatis</groupId>
		<artifactId>mybatis</artifactId>
		<version>3.5.9</version>
	</dependency>
	<dependency>
		<groupId>junit</groupId>
		<artifactId>junit</artifactId>
		<version>4.13.2</version>
		<scope>test</scope>
	</dependency>
	<dependency>
		<groupId>mysql</groupId>
		<artifactId>mysql-connector-java</artifactId>
		<version>8.0.27</version>
	</dependency>
	<dependency>
		<groupId>log4j</groupId>
		<artifactId>log4j</artifactId>
		<version>1.2.17</version>
	</dependency>
</dependencies>

<build>
	<plugins>
		<!-- 构建逆向工程的相关插件 -->
		<plugin>
			<groupId>org.mybatis.generator</groupId>
			<artifactId>mybatis-generator-maven-plugin</artifactId>
			<version>1.3.0</version>
			<!-- 插件的依赖 -->
			<dependencies>
				<!-- 核心依赖 -->
				<dependency>
					<groupId>org.mybatis.generator</groupId>
					<artifactId>mybatis-generator-core</artifactId>
					<version>1.3.2</version>
				</dependency>
				<!-- 数据库连接池 -->
				<dependency>
					<groupId>com.mchange</groupId>
					<artifactId>c3p0</artifactId>
					<version>0.9.2</version>
				</dependency>
				<!-- MySQL驱动 -->
				<dependency>
					<groupId>mysql</groupId>
					<artifactId>mysql-connector-java</artifactId>
					<version>8.0.27</version>
				</dependency>
			</dependencies>
		</plugin>
	</plugins>
</build>

二、核心配置文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
//加载外部配置文件
    <properties resource="jdbc.properties"/>
//自定义别名
    <typeAliases>
        <package name=""/>
    </typeAliases>

    <environments default="development">
        <environment id="development">
//事务管理器 
            <transactionManager type="JDBC"/>
//数据源类型
            <dataSource type="POOLED">
                <property name="driver" value="${jdbc.driver}"/>
                <property name="url" value="${jdbc.url}"/>
                <property name="username" value="${jdbc.username}"/>
                <property name="password" value="${jdbc.password}"/>
            </dataSource>
        </environment>
    </environments>
//加载映射文件
    <mappers>
    //映射文件所在的包
        <package name=""/>
        //或者写映射文件全限路径
    	//<mapper resource=""/>
    </mappers>
</configuration>

三、逆向工程的xml文件

  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>
    <!--
    targetRuntime可选值: 
   		 MyBatis3Simple: 生成基本的CRUD
   		 MyBatis3: 生成带条件的CRUD
    -->
    <context id="DB2Tables" targetRuntime="MyBatis3">
        <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
                        connectionURL="jdbc:mysql://localhost:3306/mybatis"
                        userId="root"
                        password="root">
        </jdbcConnection>
        <!-- java实体的生成-->
        <javaModelGenerator targetPackage="pojo" targetProject=".\src\main\java">
        <!--enableSubPackages是否允许子包-->
            <property name="enableSubPackages" value="true" />
        <!--trimStrings去除数据库字段名的空格-->    
            <property name="trimStrings" value="true" />
        </javaModelGenerator>
        <!-- SQL映射文件的生成 -->
        <sqlMapGenerator targetPackage="mapper"
                         targetProject=".\src\main\resources">
            <property name="enableSubPackages" value="true" />
        </sqlMapGenerator>
        <!-- Mapper接口的生成 -->
        <javaClientGenerator type="XMLMAPPER"
                             targetPackage="mapper" targetProject=".\src\main\java">
            <property name="enableSubPackages" value="true" />
        </javaClientGenerator>
        <!-- tableName：
		        数据库中的数据表名，若
		        设置为*号，可以对应所有表，此时不写domainObjectName -->
        <!-- domainObjectName属性指定生成出来的类名 -->
        <table tableName="t_emp" domainObjectName="Emp"/>
        <table tableName="t_dept" domainObjectName="Dept"/>
    </context>
</generatorConfiguration>

此时maven管理下：点击即可逆向生成实体等相关文件