JavaWeb练习之使用Mybatis Plus

JavaWeb练习之使用Mybatis Plus"/>

JavaWeb练习之使用Mybatis Plus

Mybatis-Plus使用练习

  这里使用的是2.3的版本，因为公司项目中用的就是2.3的版本。所以就没再去瞎捅咕（Mybatis-Plus2.x的说明文档）。具体作用就是用来快速生成文件模板的工具，相当于一键生成Controller、Service、Mapper和pojo类而且还支持lombok（这个只需要在配置中开启就行，当然别忘了添加依赖），可以说是相当的方便了。

Pom.xml配置相关的依赖

  这里跟Mybatis-Plus有关系的只有这三项。

1. mybatis-plus-boot-starter ➡️ Mybatis-Plus的依赖
2. velocity ➡️ 用来生成模板
3. lombok ➡️ 用来简化实体类（实际作用与Kotlin 的 data class 基本一致）

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns=".0.0" xmlns:xsi=""xsi:schemaLocation=".0.0 .0.0.xsd"><modelVersion>4.0.0</modelVersion><groupId>com.lyan</groupId><artifactId>web_note</artifactId><version>0.0.1-SNAPSHOT</version><packaging>jar</packaging><name>web_note</name><description>study,test,note</description><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.0.4.RELEASE</version><relativePath/> <!-- lookup parent from repository --></parent><properties><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding><project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding><mybatis_plus.version>2.3</mybatis_plus.version><velocity.version>1.7</velocity.version><lombok.version>1.18.0</lombok.version><java.version>1.8</java.version></properties><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-thymeleaf</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId><version>${mybatis_plus.version}</version></dependency><dependency><groupId>org.apache.velocity</groupId><artifactId>velocity</artifactId><version>${velocity.version}</version><scope>test</scope></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId><scope>runtime</scope></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>${lombok.version}</version><scope>provided</scope></dependency></dependencies><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build></project>

创建一个可以运行的类

  使用Main方法还是单元测试都行，只要能运行就行。这里我将生成的文件路径直接设到了项目中。代码有点长，根据步骤也写了注释，基本上还是很好理解的，这里就不分步骤了：

package com.lyan.web_note;import com.baomidou.mybatisplus.generator.AutoGenerator;
import com.baomidou.mybatisplus.generator.InjectionConfig;
import com.baomidou.mybatisplus.generator.config.*;
import com.baomidou.mybatisplus.generator.config.converts.MySqlTypeConvert;
import com.baomidou.mybatisplus.generator.config.po.TableInfo;
import com.baomidou.mybatisplus.generator.config.rules.DbColumnType;
import com.baomidou.mybatisplus.generator.config.rules.DbType;
import com.baomidou.mybatisplus.generator.config.rules.NamingStrategy;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;@RunWith(SpringRunner.class)
@SpringBootTest
public class MybatisGeneratorTest {//    private static final String WORK_PATH = "E:/Work/Java/MineWebTest/src/main";//项目工程目录private static final String WORK_PATH = "/Users/apple/MineFile/mine2018/web/MineWebTest/src/main";//项目工程目录private static final String OUTPUT_DIR = WORK_PATH + "/java/";//功能文件的输出路径（mvc）private static final String MAPPER_DIR = WORK_PATH + "/resources/mapper/";//映射文件的输出路径（mapper.xml）private static final String SQL_PATH = "localhost:3306";//数据库连接地址private static final String SQL_NAME = "test";//数据库名称private static final String TABLE_NAME = "week_day";//表名private static final String PARENT_NAME = "com.lyan.web_note.modules";//父包路径private static final String MODULE_NAME = TABLE_NAME;//模型的的包名@Testpublic void createWebFile() {AutoGenerator autoGenerator = new AutoGenerator();// 全局配置GlobalConfig globalConfig = new GlobalConfig();globalConfig.setOutputDir(OUTPUT_DIR);//创建的文件输出路径globalConfig.setFileOverride(true);//文件覆盖globalConfig.setActiveRecord(true);// 不需要ActiveRecord特性的请改为falseglobalConfig.setEnableCache(false);// XML 二级缓存globalConfig.setBaseResultMap(true);// XML ResultMapglobalConfig.setBaseColumnList(false);// XML columListglobalConfig.setAuthor("Lyan");//作者// 数据源配置DataSourceConfig dataSourceConfig = new DataSourceConfig();dataSourceConfig.setDbType(DbType.MYSQL);dataSourceConfig.setTypeConvert(new MySqlTypeConvert() {@Overridepublic DbColumnType processTypeConvert(String fieldType) {return super.processTypeConvert(fieldType);}});dataSourceConfig.setDriverName("com.mysql.jdbc.Driver");dataSourceConfig.setUsername("root");dataSourceConfig.setPassword("123456");dataSourceConfig.setUrl("jdbc:mysql://" + SQL_PATH + "/" + SQL_NAME + "?useUnicode=true&characterEncoding=utf8&useSSL=false");// 策略配置StrategyConfig strategyConfig = new StrategyConfig();strategyConfig.setInclude(TABLE_NAME);// 生成该表相关的文件strategyConfig.setNaming(NamingStrategy.underline_to_camel);// 表名生成策略strategyConfig.setRestControllerStyle(true);//使用RestControllerstrategyConfig.setEntityLombokModel(true);//使用插件生成实体类// 包配置PackageConfig packageConfig = new PackageConfig();packageConfig.setParent(PARENT_NAME);packageConfig.setModuleName(MODULE_NAME);packageConfig.setController("controller");packageConfig.setEntity("entity");//对生成的模板进行设置setTemplateOpinion(autoGenerator);// 生成模板文件autoGenerator.setGlobalConfig(globalConfig).setDataSource(dataSourceConfig).setStrategy(strategyConfig).setPackageInfo(packageConfig).execute();}private static void setTemplateOpinion(AutoGenerator autoGenerator) {// 注入自定义配置，可以在 VM 中使用 cfg.abc 【可无】InjectionConfig injectionConfig = new InjectionConfig() {@Overridepublic void initMap() {Map<String, Object> map = new HashMap<>();map.put("abc", this.getConfig().getGlobalConfig().getAuthor() + "-mp");this.setMap(map);}};List<FileOutConfig> fileOutConfigList = new ArrayList<>();//修改Mapper.xml文件生成的位置fileOutConfigList.add(new FileOutConfig("/templates/mapper.xml.vm") {@Overridepublic String outputFile(TableInfo tableInfo) {return MAPPER_DIR + tableInfo.getEntityName() + "Mapper.xml";}});injectionConfig.setFileOutConfigList(fileOutConfigList);autoGenerator.setCfg(injectionConfig);//关闭默认文件的生成TemplateConfig templateConfig = new TemplateConfig();templateConfig.setXml(null);templateConfig.setMapper("/vm/mapper.java.vm");templateConfig.setController("/vm/controller.java.vm");templateConfig.setService("/vm/service.java.vm");templateConfig.setServiceImpl("/vm/serviceImpl.java.vm");templateConfig.setEntity("/vm/entity.java.vm");autoGenerator.setTemplate(templateConfig);}}

  下面的就是准备的测试数据表。
　
  运行@Test方法，生成如下的目录结构。每个文件都生成到了目标路径中。
　　　　

测试运行

  配置application.yml。

spring:#配置数据源datasource:driver-class-name: com.mysql.jdbc.Driverurl: jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf8&useSSL=falseusername: rootpassword: 123456#配置模板thymeleaf:prefix: classpath:/templates/suffix: .htmlcache: falseencoding: UTF-8
server:port: 8080servlet:# 项目名称context-path: /webNote
#mybatis
mybatis-plus:mapper-locations: classpath:/mapper/*Mapper.xmlglobal-config:#主键类型  0:"数据库ID自增", 1:"用户输入ID",2:"全局唯一ID (数字类型唯一ID)", 3:"全局唯一ID UUID";id-type: 2#字段策略 0:"忽略判断",1:"非 NULL 判断"),2:"非空判断"field-strategy: 2#驼峰下划线转换db-column-underline: true#刷新mapper 调试神器refresh-mapper: true# SQL 解析缓存，开启后多租户 @SqlParser 注解生效sql-parser-cache: trueconfiguration:map-underscore-to-camel-case: truecache-enabled: false

  注意一下给Mapper的接口映射文件配置上@Mapper，这样就不用配置@MapperSpan了。我这里偷了个懒直接修改的模板文件，直接在模板中加上了@Mapper。

package ${package.Mapper};import ${package.Entity}.${entity};
import ${superMapperClassPackage};
import org.apache.ibatis.annotations.Mapper;
import org.springframework.stereotype.Component;/*** $!{tablement} Mapper 接口* @author ${author}* @since ${date}*/
@Mapper
@Component
public interface ${table.mapperName} extends ${superMapperClass}<${entity}> {}

  最后在WeekDayController中写一个接口，将表中的数据以Json形式返回。

package com.lyan.web_note.modules.week_day.controller;import com.baomidou.mybatisplus.mapper.EntityWrapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import com.lyan.web_note.modules.week_day.entity.WeekDay;
import com.lyan.web_note.modules.week_day.service.IWeekDayService;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;import java.util.List;/***  前端控制器* @author Lyan* @since 2018-09-17*/
@RestController
@RequestMapping("/week_day/weekDay")
@SuppressWarnings("SpringJavaAutowiredFieldsWarningInspection")
public class WeekDayController {@Autowiredprivate IWeekDayService iWeekDayService;@GetMapping("/weeks")@ResponseBodypublic List<WeekDay> getWeeks(){return iWeekDayService.selectList(new EntityWrapper<>());}
}

  运行结果如下：