SpringBoot 整合 Mybatis generator

一、简介：

​ Mybatis generator 是 MyBatis 官方提供的代码生成器，可以根据数据库生成 model、mapper.xml、mapper 接口和 Example，通常情况下的单表查询不用再手写 mapper。

二、使用步骤：

1. 创建 SpringBoot 项目，导入 Maven 坐标

   <dependencies>
       <!--SpringBoot通用依赖模块-->
       <dependency>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-web</artifactId>
       </dependency>
       <dependency>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-actuator</artifactId>
       </dependency>
       <dependency>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-aop</artifactId>
       </dependency>
       <dependency>
           <groupId>org.springframework.boot</groupId>
           <artifactId>spring-boot-starter-test</artifactId>
           <scope>test</scope>
       </dependency>
       <!--MyBatis分页插件-->
       <dependency>
           <groupId>com.github.pagehelper</groupId>
           <artifactId>pagehelper-spring-boot-starter</artifactId>
           <version>1.2.10</version>
       </dependency>
       <!--集成druid连接池-->
       <dependency>
           <groupId>com.alibaba</groupId>
           <artifactId>druid-spring-boot-starter</artifactId>
           <version>1.1.22</version>
       </dependency>
       <!-- MyBatis 生成器 -->
       <dependency>
           <groupId>org.mybatis.generator</groupId>
           <artifactId>mybatis-generator-core</artifactId>
           <version>1.4.0</version>
       </dependency>
       <!--Mysql数据库驱动-->
       <dependency>
           <groupId>mysql</groupId>
           <artifactId>mysql-connector-java</artifactId>
           <version>8.0.15</version>
       </dependency>
       <!-- swagger2 和 swagger-ui -->
       <dependency>
           <groupId>io.springfox</groupId>
           <artifactId>springfox-swagger2</artifactId>
           <version>2.9.2</version>
       </dependency>
       <dependency>
           <groupId>io.springfox</groupId>
           <artifactId>springfox-swagger-ui</artifactId>
           <version>2.9.2</version>
       </dependency>
   </dependencies>
   

2. 在 application.yml 中添加数据源配置和 MyBatis 的 mapper.xml 的路径配置

   server:
     port: 8080
   
   spring:
     datasource:
       url: jdbc:mysql://localhost:3306/mall?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai
       username: root
       password: root
   
   mybatis:
     mapper-locations:
       - classpath:mapper/*.xml
       - classpath*:com/**/mapper/*.xml
   

3. 配置数据库连接，Mybatis generator生成model、mapper接口及mapper.xml的路径

   在项目的 resource 下创建 generatorConfig.xml 文件:

   <?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>
       <!-- 连接数据库需要的信息-->
       <properties resource="generator.properties"/>
       <context id="MySqlContext" targetRuntime="MyBatis3" defaultModelType="flat">
           <property name="beginningDelimiter" value="`"/>
           <property name="endingDelimiter" value="`"/>
           <property name="javaFileEncoding" value="UTF-8"/>
           <!-- 为模型生成序列化方法-->
           <plugin type="org.mybatis.generator.plugins.SerializablePlugin"/>
           <!-- 为生成的Java模型创建一个toString方法 -->
           <plugin type="org.mybatis.generator.plugins.ToStringPlugin"/>
           <!--生成mapper.xml时覆盖原文件-->
           <plugin type="org.mybatis.generator.plugins.UnmergeableXmlMappersPlugin" />
   
           <commentGenerator type="cn.blue.CommentGenerator">
               <!-- 是否去除自动生成的注释 true：是 ： false:否 -->
               <property name="suppressAllComments" value="true"/>
               <property name="suppressDate" value="true"/>
               <property name="addRemarkComments" value="true"/>
           </commentGenerator>
   
           <jdbcConnection driverClass="${jdbc.driverClass}"
                           connectionURL="${jdbc.connectionURL}"
                           userId="${jdbc.userId}"
                           password="${jdbc.password}">
               <!--解决mysql驱动升级到8.0后不生成指定数据库代码的问题-->
               <property name="nullCatalogMeansCurrent" value="true" />
           </jdbcConnection>
   
           <javaModelGenerator targetPackage="cn.blue.mbg.model" targetProject="mall-mbg\src\main\java"/>
   
           <sqlMapGenerator targetPackage="cn.blue.mbg.mapper" targetProject="mall-mbg\src\main\resources"/>
   
           <javaClientGenerator type="XMLMAPPER" targetPackage="cn.blue.mbg.mapper"
                                targetProject="mall-mbg\src\main\java"/>
           <!--生成全部表tableName设为%-->
           <table tableName="%">
               <generatedKey column="id" sqlStatement="MySql" identity="true"/>
           </table>
       </context>
   </generatorConfiguration>
   

   generator.properties文件:

   jdbc.driverClass=com.mysql.cj.jdbc.Driver
   jdbc.connectionURL=jdbc:mysql://localhost:3306/数据库名?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai
   jdbc.userId=root
   jdbc.password=root
   

4. 自定义注释生成器:

   package cn.blue;
   
   import org.mybatis.generator.api.IntrospectedColumn;
   import org.mybatis.generator.api.IntrospectedTable;
   import org.mybatis.generator.api.dom.java.CompilationUnit;
   import org.mybatis.generator.api.dom.java.Field;
   import org.mybatis.generator.api.dom.java.FullyQualifiedJavaType;
   import org.mybatis.generator.internal.DefaultCommentGenerator;
   import org.mybatis.generator.internal.util.StringUtility;
   
   import java.util.Properties;
   
   /**
    * 自定义注释生成器
    * Created by macro on 2018/4/26.
    */
   public class CommentGenerator extends DefaultCommentGenerator {
       private boolean addRemarkComments = false;
       private static final String EXAMPLE_SUFFIX="Example";
       private static final String MAPPER_SUFFIX="Mapper";
       private static final String API_MODEL_PROPERTY_FULL_CLASS_NAME="io.swagger.annotations.ApiModelProperty";
   
       /**
        * 设置用户配置的参数
        */
       @Override
       public void addConfigurationProperties(Properties properties) {
           super.addConfigurationProperties(properties);
           this.addRemarkComments = StringUtility.isTrue(properties.getProperty("addRemarkComments"));
       }
   
       /**
        * 给字段添加注释
        */
       @Override
       public void addFieldComment(Field field, IntrospectedTable introspectedTable,
                                   IntrospectedColumn introspectedColumn) {
           String remarks = introspectedColumn.getRemarks();
           //根据参数和备注信息判断是否添加备注信息
           if(addRemarkComments&&StringUtility.stringHasValue(remarks)){
   //            addFieldJavaDoc(field, remarks);
               //数据库中特殊字符需要转义
               if(remarks.contains("\"")){
                   remarks = remarks.replace("\"","'");
               }
               //给model的字段添加swagger注解
               field.addJavaDocLine("@ApiModelProperty(value = \""+remarks+"\")");
           }
       }
   
       /**
        * 给model的字段添加注释
        */
       private void addFieldJavaDoc(Field field, String remarks) {
           //文档注释开始
           field.addJavaDocLine("/**");
           //获取数据库字段的备注信息
           String[] remarkLines = remarks.split(System.getProperty("line.separator"));
           for(String remarkLine:remarkLines){
               field.addJavaDocLine(" * "+remarkLine);
           }
           addJavadocTag(field, false);
           field.addJavaDocLine(" */");
       }
   
       @Override
       public void addJavaFileComment(CompilationUnit compilationUnit) {
           super.addJavaFileComment(compilationUnit);
           //只在model中添加swagger注解类的导入
           if(!compilationUnit.getType().getFullyQualifiedName().contains(MAPPER_SUFFIX)&&!compilationUnit.getType().getFullyQualifiedName().contains(EXAMPLE_SUFFIX)){
               compilationUnit.addImportedType(new FullyQualifiedJavaType(API_MODEL_PROPERTY_FULL_CLASS_NAME));
           }
       }
   }
   
   

5. 运行Generator的main函数生成代码:

   package cn.blue;
   
   import org.mybatis.generator.api.MyBatisGenerator;
   import org.mybatis.generator.config.Configuration;
   import org.mybatis.generator.config.xml.ConfigurationParser;
   import org.mybatis.generator.internal.DefaultShellCallback;
   
   import java.io.InputStream;
   import java.util.ArrayList;
   import java.util.List;
   
   /**
    * 用于生产MBG的代码
    * Created by macro on 2018/4/26.
    */
   public class Generator {
       public static void main(String[] args) throws Exception {
           //MBG 执行过程中的警告信息
           List<String> warnings = new ArrayList<String>();
           //当生成的代码重复时，覆盖原代码
           boolean overwrite = true;
           //读取我们的 MBG 配置文件
           InputStream is = Generator.class.getResourceAsStream("/generatorConfig.xml");
           ConfigurationParser cp = new ConfigurationParser(warnings);
           Configuration config = cp.parseConfiguration(is);
           is.close();
   
           DefaultShellCallback callback = new DefaultShellCallback(overwrite);
           //创建 MBG
           MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);
           //执行生成代码
           myBatisGenerator.generate(null);
           //输出警告信息
           for (String warning : warnings) {
               System.out.println(warning);
           }
       }
   }
   

   此时已经可以根据数据库生产代码，下面代码是实现 PmsBrand 表中的添加、修改、删除及分页查询，检验生成的代码
   

6. 用于配置需要动态生成的mapper接口的路径:

   package com.macro.mall.tiny.config;
   
   import org.mybatis.spring.annotation.MapperScan;
   import org.springframework.context.annotation.Configuration;
   
   /**
    * MyBatis配置类
    * Created by macro on 2019/4/8.
    */
   @Configuration
   @MapperScan("cn.blue.mbg.mapper")
   public class MyBatisConfig {
   }
   

7. Controller

   
   
   /**
    * 品牌管理Controller
    * Created by macro on 2019/4/19.
    */
   @Controller
   @RequestMapping("/brand")
   public class PmsBrandController {
       @Autowired
       private PmsBrandService demoService;
   
       private static final Logger LOGGER = LoggerFactory.getLogger(PmsBrandController.class);
   
       @RequestMapping(value = "listAll", method = RequestMethod.GET)
       @ResponseBody
       public CommonResult<List<PmsBrand>> getBrandList() {
           return CommonResult.success(demoService.listAllBrand());
       }
   
       @RequestMapping(value = "/create", method = RequestMethod.POST)
       @ResponseBody
       public CommonResult createBrand(@RequestBody PmsBrand pmsBrand) {
           CommonResult commonResult;
           int count = demoService.createBrand(pmsBrand);
           if (count == 1) {
               commonResult = CommonResult.success(pmsBrand);
               LOGGER.debug("createBrand success:{}", pmsBrand);
           } else {
               commonResult = CommonResult.failed("操作失败");
               LOGGER.debug("createBrand failed:{}", pmsBrand);
           }
           return commonResult;
       }
   
       @RequestMapping(value = "/update/{id}", method = RequestMethod.POST)
       @ResponseBody
       public CommonResult updateBrand(@PathVariable("id") Long id, @RequestBody PmsBrand pmsBrandDto, BindingResult result) {
           CommonResult commonResult;
           int count = demoService.updateBrand(id, pmsBrandDto);
           if (count == 1) {
               commonResult = CommonResult.success(pmsBrandDto);
               LOGGER.debug("updateBrand success:{}", pmsBrandDto);
           } else {
               commonResult = CommonResult.failed("操作失败");
               LOGGER.debug("updateBrand failed:{}", pmsBrandDto);
           }
           return commonResult;
       }
   
       @RequestMapping(value = "/delete/{id}", method = RequestMethod.GET)
       @ResponseBody
       public CommonResult deleteBrand(@PathVariable("id") Long id) {
           int count = demoService.deleteBrand(id);
           if (count == 1) {
               LOGGER.debug("deleteBrand success :id={}", id);
               return CommonResult.success(null);
           } else {
               LOGGER.debug("deleteBrand failed :id={}", id);
               return CommonResult.failed("操作失败");
           }
       }
   
       @RequestMapping(value = "/list", method = RequestMethod.GET)
       @ResponseBody
       public CommonResult<CommonPage<PmsBrand>> listBrand(@RequestParam(value = "pageNum", defaultValue = "1") Integer pageNum,
                                                           @RequestParam(value = "pageSize", defaultValue = "3") Integer pageSize) {
           List<PmsBrand> brandList = demoService.listBrand(pageNum, pageSize);
           return CommonResult.success(CommonPage.restPage(brandList));
       }
   
       @RequestMapping(value = "/{id}", method = RequestMethod.GET)
       @ResponseBody
       public CommonResult<PmsBrand> brand(@PathVariable("id") Long id) {
           return CommonResult.success(demoService.getBrand(id));
       }
   }
   

8. Service 接口

   public interface PmsBrandService {
       List<PmsBrand> listAllBrand();
   
       int createBrand(PmsBrand brand);
   
       int updateBrand(Long id, PmsBrand brand);
   
       int deleteBrand(Long id);
   
       List<PmsBrand> listBrand(int pageNum, int pageSize);
   
       PmsBrand getBrand(Long id);
   }
   

9. `Service 实现

   @Service
   public class PmsBrandServiceImpl implements PmsBrandService {
       @Autowired
       private PmsBrandMapper brandMapper;
   
       @Override
       public List<PmsBrand> listAllBrand() {
           return brandMapper.selectByExample(new PmsBrandExample());
       }
   
       @Override
       public int createBrand(PmsBrand brand) {
           return brandMapper.insertSelective(brand);
       }
   
       @Override
       public int updateBrand(Long id, PmsBrand brand) {
           brand.setId(id);
           return brandMapper.updateByPrimaryKeySelective(brand);
       }
   
       @Override
       public int deleteBrand(Long id) {
           return brandMapper.deleteByPrimaryKey(id);
       }
   
       @Override
       public List<PmsBrand> listBrand(int pageNum, int pageSize) {
           PageHelper.startPage(pageNum, pageSize);
           return brandMapper.selectByExample(new PmsBrandExample());
       }
   
       @Override
       public PmsBrand getBrand(Long id) {
           return brandMapper.selectByPrimaryKey(id);
       }
   }