Mapper系列二：逆向工程

蔚落 2022-04-25 01:22 232阅读 0赞

参考文档： [https://github.com/abel533/Mapper/wiki/4.1.mappergenerator][https_github.com_abel533_Mapper_wiki_4.1.mappergenerator]  
原生 MyBatis 逆向工程和通用 Mapper 逆向工程对比：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpemhpcWlhbmcxMjE3_size_16_color_FFFFFF_t_70]  
1、引入相关依赖

<dependencies>
    		<dependency>
    			<groupId>tk.mybatis</groupId>
    			<artifactId>mapper</artifactId>
    			<version>4.0.0-beta3</version>
    		</dependency>
    		<dependency>
    			<groupId>org.mybatis</groupId>
    			<artifactId>mybatis</artifactId>
    			<version>3.2.8</version>
    		</dependency>
    		<dependency>
    			<groupId>mysql</groupId>
    			<artifactId>mysql-connector-java</artifactId>
    			<version>${mysql.version}</version>
    		</dependency>
    	</dependencies>

2、在pom.xml文件中添加properties

<properties>
    		
    		
    		<targetJavaProject>${basedir}/src/main/java</targetJavaProject>
    
    		
    		<targetMapperPackage>com.atguigu.shop.mappers</targetMapperPackage>
    
    		
    		<targetModelPackage>com.atguigu.shop.entities</targetModelPackage>
    
    		
    		<targetResourcesProject>${basedir}/src/main/resources</targetResourcesProject>
    
    		
    		<targetXMLPackage>mappers</targetXMLPackage>
    
    		
    		<mapper.version>4.0.0-beta3</mapper.version>
    
    		
    		<mysql.version>5.1.37</mysql.version>
    	</properties>

3、在pom.xml文件中添加plugin

<build>
    		<plugins>
    			<plugin>
    				<groupId>org.mybatis.generator</groupId>
    				<artifactId>mybatis-generator-maven-plugin</artifactId>
    				<version>1.3.2</version>
    
    				
    				<configuration>
    					<configurationFile>${basedir}/src/main/resources/generator/generatorConfig.xml</configurationFile>
    					<overwrite>true</overwrite>
    					<verbose>true</verbose>
    				</configuration>
    
    				
    				<dependencies>
    					<dependency>
    						<groupId>mysql</groupId>
    						<artifactId>mysql-connector-java</artifactId>
    						<version>${mysql.version}</version>
    					</dependency>
    					<dependency>
    						<groupId>tk.mybatis</groupId>
    						<artifactId>mapper</artifactId>
    						<version>${mapper.version}</version>
    					</dependency>
    				</dependencies>
    			</plugin>
    		</plugins>
    	</build>

4、创建config.properties

# Database connection information
    jdbc.driverClass = com.mysql.jdbc.Driver
    jdbc.url = jdbc:mysql://localhost:3306/mapper
    jdbc.user = root
    jdbc.password = root
    
    #c3p0
    jdbc.maxPoolSize=50
    jdbc.minPoolSize=10
    jdbc.maxStatements=100
    jdbc.testConnection=true
    
    # mapper
    mapper.plugin = tk.mybatis.mapper.generator.MapperPlugin
    mapper.Mapper = tk.mybatis.mapper.common.Mapper

5、创建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>
    	
    	<properties resource="config.properties" />
    
    	<context id="Mysql" targetRuntime="MyBatis3Simple"
    		defaultModelType="flat">
    		<property name="beginningDelimiter" value="`" />
    		<property name="endingDelimiter" value="`" />
    
    		
    		<plugin type="${mapper.plugin}">
    			<property name="mappers" value="${mapper.Mapper}" />
    		</plugin>
    
    		
    		<jdbcConnection 
    			driverClass="${jdbc.driverClass}"
    			connectionURL="${jdbc.url}" 
    			userId="${jdbc.user}" 
    			password="${jdbc.password}">
    		</jdbcConnection>
    	
    		
    		<javaModelGenerator 
    			targetPackage="${targetModelPackage}"
    			targetProject="${targetJavaProject}" />
    
    		
    		<sqlMapGenerator 
    			targetPackage="${targetXMLPackage}"
    			targetProject="${targetResourcesProject}" />
    
    		
    		<javaClientGenerator 
    			targetPackage="${targetMapperPackage}"
    			targetProject="${targetJavaProject}" 
    			type="XMLMAPPER" />
    
    		
    		
    		
    		
    		<table tableName="tabple_emp" domainObjectName="Employee">
    			
    			<generatedKey column="emp_id" sqlStatement="Mysql" identity="true" />
    		</table>
    	</context>
    </generatorConfiguration>

6、运行逆向工程  
 在pom.xml 这一级目录的命令行窗口。执行maven命令`mvn mybatis-generator:generate`  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpemhpcWlhbmcxMjE3_size_16_color_FFFFFF_t_70 1]  
测试：  
 创建mybatis配置文件mybatis-config.xml

<?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>
    
    	
    	<properties resource="jdbc.properties"/>
    	
    	
    	<environments default="development">
    		
    		<environment id="development">
    			
    			<transactionManager type="JDBC"/>
    			
    			<dataSource type="POOLED">
    				<property name="username" value="${jdbc.user}"/>
    				<property name="password" value="${jdbc.password}"/>
    				<property name="driver" value="${jdbc.driver}"/>
    				<property name="url" value="${jdbc.url}"/>
    			</dataSource>
    		</environment>
    	</environments>
    	
    	<mappers>
    		<package name="com.atguigu.shop.mappers"/>
    	</mappers>
    
    </configuration>

编写测试类MBGTest

public class MBGTest {
    	
    	public static void main(String[] args) {
    		SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
    		InputStream inputStream = MBGTest.class.getClassLoader().getResourceAsStream("mybatis-config.xml");
    		SqlSessionFactory factory = builder.build(inputStream);
    		SqlSession session = factory.openSession();
    		
    		//按照Java方式整合通用Mapper的特殊设置
    		//i.创建MapperHelper对象
    		MapperHelper mapperHelper = new MapperHelper();
    		
    		//ii.通过MapperHelper对象对MyBatis原生的Configuration对象进行处理
    		Configuration configuration = session.getConfiguration();
    		mapperHelper.processConfiguration(configuration);
    
    		EmployeeMapper mapper = session.getMapper(EmployeeMapper.class);
    		
    		Iterator<Employee> iterator = mapper.selectAll().iterator();
    		
    		while (iterator.hasNext()) {
    			Employee employee = iterator.next();
    			System.out.println(employee);
    		}
    		
    	}
    
    }

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpemhpcWlhbmcxMjE3_size_16_color_FFFFFF_t_70 2]

[https_github.com_abel533_Mapper_wiki_4.1.mappergenerator]: https://github.com/abel533/Mapper/wiki/4.1.mappergenerator
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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpemhpcWlhbmcxMjE3_size_16_color_FFFFFF_t_70 1]: /images/20220210/ba1c2935f6474166a6d6fee80bb6b834.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2xpemhpcWlhbmcxMjE3_size_16_color_FFFFFF_t_70 2]: /images/20220210/fe3b3379d32346ac999158f34766317a.png