MyBatis Generator系列(一)----MyBatis Generator简介

红太狼 2022-06-08 03:53 239阅读 0赞

一、什么是MyBatis Generator ?

MyBatis Generator是一个可以用来生成Mybatis dao,entity,Mapper文件的一个工具,在项目的过程中可以省去很多重复的工作,我们只要在MyBatis Generator的配置文件中配置好要生成的表名与包名，然后运行一条命令就会生成一堆文件。

目前最新的版本是:1.3.5

一些资料:

[MyBatis Generator中文文档][MyBatis Generator]

[mybatis-generator-gui][]

二、MyBatis Generator配置文件

MyBatis Generator主要是根据是根据generatorConfig.xml来生成文件，generatorConfig配置详情如下:

<?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="mysql" defaultModelType="hierarchical" targetRuntime="MyBatis3Simple" >
    
        
        <property name="autoDelimitKeywords" value="false"/>
        
        <property name="javaFileEncoding" value="UTF-8"/>
        
        <property name="javaFormatter" value="org.mybatis.generator.api.dom.DefaultJavaFormatter"/>
        
        <property name="xmlFormatter" value="org.mybatis.generator.api.dom.DefaultXmlFormatter"/>
    
        
        <property name="beginningDelimiter" value="`"/>
        <property name="endingDelimiter" value="`"/>
    
        
        <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql:///pss" userId="root" password="admin">
            
        </jdbcConnection>
    
        
        <javaTypeResolver type="org.mybatis.generator.internal.types.JavaTypeResolverDefaultImpl">
            
            <property name="forceBigDecimals" value="false"/>
        </javaTypeResolver>
    
    
        
        <javaModelGenerator targetPackage="com._520it.mybatis.domain" targetProject="src/main/java">
            
            <property name="constructorBased" value="false"/>
    
            
            <property name="enableSubPackages" value="true"/>
    
            
            <property name="immutable" value="false"/>
    
            
            <property name="rootClass" value="com._520it.mybatis.domain.BaseDomain"/>
    
            
            <property name="trimStrings" value="true"/>
        </javaModelGenerator>
    
    
        
        <sqlMapGenerator targetPackage="com._520it.mybatis.mapper" targetProject="src/main/resources">
            
            <property name="enableSubPackages" value="true"/>
        </sqlMapGenerator>
    
    
        
        <javaClientGenerator targetPackage="com._520it.mybatis.mapper" type="ANNOTATEDMAPPER" targetProject="src/main/java">
            
            <property name="enableSubPackages" value="true"/>
    
            
        </javaClientGenerator>
    
        
        <table tableName="userinfo" >
    
            
            <property name="constructorBased" value="false"/>
    
            
            <property name="ignoreQualifiersAtRuntime" value="false"/>
    
            
            <property name="immutable" value="false"/>
    
            
            <property name="modelOnly" value="false"/>
    
            
    
            
    
            
    
            
    
            
    
            
            <property name="selectAllOrderByClause" value="age desc,username asc"/>
    
            
            <property name="useActualColumnNames" value="false"/>
    
    
            
    
            
    
    
             
             <columnOverride column="username">
                 
                 <property name="property" value="userName"/>
    
                 
    
                 
    
                 
    
                 
             </columnOverride>
    
             
        </table>
    
    </context>
    
    </generatorConfiguration>

mysql配置方式:

Oracle配置方式:

三、MyBatis Generator怎么用

有四种方式可用

**第一种: 命令行式创建**

在mybatis-generator-core-1.3.2\\lib目录下配置generatorConfig.xml文件如下:

<?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>  
      
        <classPathEntry  location="mysql-connector-java-5.1.25-bin.jar"/>  
        <context id="DB2Tables"  targetRuntime="MyBatis3">  
            <commentGenerator>  
                <property name="suppressDate" value="true"/>  
                  
                <property name="suppressAllComments" value="true"/>  
            </commentGenerator>  
               
            <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://localhost:3306/test" userId="root" password="root">  
            </jdbcConnection>  
            <javaTypeResolver>  
                <property name="forceBigDecimals" value="false"/>  
            </javaTypeResolver>  
              
            <javaModelGenerator targetPackage="com.fendo.bean" targetProject="src/main/java">  
                <property name="enableSubPackages" value="true"/>  
                <property name="trimStrings" value="true"/>  
            </javaModelGenerator>  
              
            <sqlMapGenerator targetPackage="com.fendo.mapper" targetProject="src/main/java">  
                <property name="enableSubPackages" value="true"/>  
            </sqlMapGenerator>  
              
            <javaClientGenerator type="XMLMAPPER" targetPackage="com.fendo.dao" targetProject="src/main/java">  
                <property name="enableSubPackages" value="true"/>  
            </javaClientGenerator>  
              
            <table tableName="t_user" domainObjectName="Usr" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false"></table>
        </context>  
    </generatorConfiguration>

在CMD下执行命令:

java -jar mybatis-generator-core-1.3.2.jar -configfile generatorConfig.xml -overwrite

或者在该目录下新建一个install.cmd文件

echo off
    set JAVA_HOME=C:\work\java\jdk1.8.0_102
    set M2_HOME=C:\work\Java\apache-maven-3.0.3
    
    set PATHP=%PATH%
    set PATH=%PATH%;%M2_HOME%\bin;%ANT_HOME%\bin
    
    Java -jar mybatis-generator-core-1.3.2.jar -configfile generatorConfig.xml -overwrite
    
    set PATHP=%PATH%

**第二种: 使用mybatis-generator-maven-plugin插件自动生成MyBatis代码**

1. 首先需要创建一个Maven项目  
2.  修改pom.xml文件

先加入mybatis-generator依赖:

<groupId>org.mybatis.generator</groupId>
              <artifactId>mybatis-generator-core</artifactId>
              <version>1.3.2</version>
     </dependency>

然后在plugins标签下加入以下内容:

<plugin>
                   <groupId>org.mybatis.generator</groupId>
                   <artifactId>mybatis-generator-maven-plugin</artifactId>
                   <version>1.3.2</version>
                    <configuration>
                       <configurationFile>src\main\resources\generatorConfig.xml</configurationFile>
                       <verbose>true</verbose>
                        <overwrite>true</overwrite>
                    </configuration>
                    <executions>
                        <execution>
                            <id>GenerateMyBatis Artifacts</id>
                            <goals>
                               <goal>generate</goal>
                            </goals>
                        </execution>
                    </executions>
     </plugin>

如果提示:

Plugin execution not covered by lifecycle configuration: org.mybatis.generator:mybatis-generator-maven-plugin:1.3.2:generate (execution: GenerateMyBatis Artifacts, phase: generate-sources)

错误，需要在<plugins>上面加上<pluginManagement>标签就行了。

3.运行方法：在eclipse 中，选择pom.xml文件，击右键先择Run AS——>Maven Build… ——>在Goals框中输入：mybatis-generator:generate

![20171005114701483][]

**第三种方式: 通过MybatisGenerator类和配置文件生成**

1.配置文件使用上面的generatorConfig.xml  
2.创建MybatisGenerator类

package com.fendo.pays.utils;
    
    import java.io.File;
    import java.io.IOException;
    import java.sql.SQLException;
    import java.util.ArrayList;
    import java.util.List;
    
    import org.mybatis.generator.api.MyBatisGenerator;
    import org.mybatis.generator.config.Configuration;
    import org.mybatis.generator.config.xml.ConfigurationParser;
    import org.mybatis.generator.exception.InvalidConfigurationException;
    import org.mybatis.generator.exception.XMLParserException;
    import org.mybatis.generator.internal.DefaultShellCallback;
    
    /**   
     * @Title: MybatisGenerator.java 
     * @Package com.fendo.pays.utils 
     * @Description: MybatisGenerator类和配置文件生成
     * @author fendo
     * @date 2017年10月5日 上午11:48:26 
     * @version V1.0   
    */
    public class MybatisGenerator {
    
    	public static void main(String[] args) {
            try {
                System.out.println("**************start generator***************");
                List<String> warnings = new ArrayList<String>();
                boolean overwrite = true;
                File configFile = new File(MybatisGenerator.class.getResource("/generatorConfig.xml").getFile());
                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);
                System.out.println("*******************end generator*************");
            } catch (IOException e) {
                e.printStackTrace();
            } catch (XMLParserException e) {
                e.printStackTrace();
            } catch (InterruptedException e) {
                e.printStackTrace();
            } catch (SQLException e) {
                e.printStackTrace();
            } catch (InvalidConfigurationException e) {
                e.printStackTrace();
            }
        }
    }

然后运行就会自动的生成代码。

**第四种方式: 通过GeneratorAntTask类和配置文件生成**

由于使用了Ant所以要加入Ant的依赖:

<dependency>
    	  <groupId>ant</groupId>
    	   <artifactId>ant</artifactId>
    	   <version>1.6.5</version>
    </dependency>

然后新建一个类来测试:

package com.fendo.pays.utils;
    
    import org.mybatis.generator.ant.GeneratorAntTask;
    
    
    /**   
     * @Title: GeneratorAntTask.java 
     * @Package com.fendo.pays.utils 
     * @Description: TODO
     * @author fendo
     * @date 2017年10月5日 上午11:57:32 
     * @version V1.0   
    */
    public class GeneratorAnt {
    
    	 public static void main(String[] args) {
    	   try {
    	          GeneratorAntTask task = new GeneratorAntTask();
    	          task.setConfigfile("src/main/resources/generatorConfig.xml");  //（配置文件具体path）
    	          task.execute();
    	        } catch (Exception e) {
    	            e.printStackTrace();
    	        }
    	 }
    }

[MyBatis Generator]: http://git.oschina.net/free/Mybatis_Utils/blob/master/MybatisGeneator/MybatisGeneator.md
[mybatis-generator-gui]: https://github.com/zouzg/mybatis-generator-gui
[20171005114701483]: /images/20220608/ff80072859d0496fa0683f84b529321a.png