mybais逆向工程快速生成实体和基本xml

妖狐艹你老母 2023-10-18 16:45 117阅读 0赞

在ssm或者使用mybatis的项目中，如果有大量的表需要建设实体到数据库的表映射关系，在程序中一个个手动创建对象是很费时间的事情，mybatis提供了一个很好用的插件可以帮助我们快速生成基本的实体对象到数据库的表映射以及xml文件，下面就看看具体的配置，

1、pom依赖文件，

<properties>
    		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    	</properties>
    	
    	
    	<dependencies>
    			
    		
    		<dependency>
    		    <groupId>org.springframework.boot</groupId>
    		    <artifactId>spring-boot-starter-log4j</artifactId>
    		    <version>1.3.8.RELEASE</version>
    		</dependency>
    		
            
    		<dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid</artifactId>
                <version>1.1.0</version>
            </dependency>
            <dependency>
                <groupId>com.alibaba</groupId>
                <artifactId>druid-spring-boot-starter</artifactId>
                <version>1.1.0</version>
            </dependency>
            
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>5.1.41</version>
            </dependency>
    
            
    		<dependency>
    		    <groupId>org.mybatis.spring.boot</groupId>
    		    <artifactId>mybatis-spring-boot-starter</artifactId>
    		    <version>1.3.1</version>
    		</dependency>
    		
    		<dependency>
    		    <groupId>tk.mybatis</groupId>
    		    <artifactId>mapper-spring-boot-starter</artifactId>
    		    <version>1.2.4</version>
    		</dependency>
    		
    		<dependency>
    		    <groupId>com.github.pagehelper</groupId>
    		    <artifactId>pagehelper-spring-boot-starter</artifactId>
    		    <version>1.2.3</version>
    		</dependency>
    	
    		
     		<dependency>
                <groupId>org.mybatis.generator</groupId>
                <artifactId>mybatis-generator-core</artifactId>
                <version>1.3.2</version>
                <scope>compile</scope>
                <optional>true</optional>
            </dependency>
    	</dependencies>

2、项目结构，  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nY29uZ3lpNDIw_size_16_color_FFFFFF_t_70]  
这里面有个很重要的配置文件就是 generatorConfig.xml ,通过配置这里面的数据库连接信息将数据库的表生成到我们的项目中，具体配置如下，

<?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="MysqlContext" targetRuntime="MyBatis3Simple" defaultModelType="flat">
            <property name="beginningDelimiter" value="`"/>
            <property name="endingDelimiter" value="`"/>
    
            <plugin type="tk.mybatis.mapper.generator.MapperPlugin">
                <property name="mappers" value="com.congge.utils.MyMapper"/>
            </plugin>
    
            <jdbcConnection driverClass="com.mysql.jdbc.Driver"
                            connectionURL="jdbc:mysql://localhost:3306/muxin-dev"
                            userId="root"
                            password="root">
            </jdbcConnection>
    
            
            <javaModelGenerator targetPackage="com.congge.entity" targetProject="src/main/java"/>
    
    		
            <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources/mybatis"/>
    
    		
            <javaClientGenerator targetPackage="com.congge.mapper" targetProject="src/main/java" type="XMLMAPPER"/>
    
    
    		<table tableName="users"></table>
    		<table tableName="my_friends"></table>
    		<table tableName="friends_request"></table>
    		<table tableName="chat_msg"></table>
    		 
        </context>
    </generatorConfiguration>

对应的数据库里面提前创建好了几张表，  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nY29uZ3lpNDIw_size_16_color_FFFFFF_t_70 1]  
关于这个配置文件，没有太多可说的，大家很容易看明白，配置里面有个工具类和项目中的这个类对应，  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nY29uZ3lpNDIw_size_16_color_FFFFFF_t_70 2]

对应项目中的这个接口，

/**
     * 继承自己的MyMapper
     *
     */
    public interface MyMapper<T> extends Mapper<T>, MySqlMapper<T> {
        //TODO
        //FIXME 特别注意，该接口不能被扫描到，否则会出错
    }

最后就是我们的主启动类，执行这个类里面的main函数即可，

public class GeneratorDisplay {
    
    	public void generator() throws Exception{
    
    		List<String> warnings = new ArrayList<String>();
    		boolean overwrite = true;
    		//指定 逆向工程配置文件
    		File configFile = new File("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 {
    			GeneratorDisplay generatorSqlmap = new GeneratorDisplay();
    			generatorSqlmap.generator();
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		
    	}
    }

执行一下，可以看到实体类和xml文件已经生成，注意需要刷新一下目录，  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nY29uZ3lpNDIw_size_16_color_FFFFFF_t_70 3]  
有个问题需要注意，就是当你修改配置文件或者表结构的时候，如果要重新获得实体类和xml文件，必须要删掉之前的重新生成才行。

**本篇到此结束，感谢观看！**

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