1、介绍
Mybatis
Mybatis 是操作数据库的框架:提供一种Mapper类,支持用Java代码对数据库进行增删改查。 缺点:需要先在xml中写好SQL语句;
Mybatis Generator
自动为Mybatis生成简单的增删改查SQL语句的工具
Mybatis-Plus
MyBatis-Plus 是一个Mybatis 增强版工具,在 MyBatis 基础上扩充了功能(由国人团队苞米豆开发)。 作用:为了简化开发效率。
Mybatis Plus Generator
比Mybatis Generator更加强大,支持功能更多,可自动生成: Entity、Mapper、Service、Controller等
2、Mybatis Plus Generator用法演示
2.1、工程创建与依赖配置
通过IDEA新建Spring工程,在工程的pom.xml文件中配置依赖:
org.springframework.bootspring-boot-starter-weborg.springframework.bootspring-boot-devtoolsruntimetruemysqlmysql-connector-javaruntimeorg.projectlomboklomboktrueorg.springframework.bootspring-boot-starter-testtestcom.baomidoumybatis-plus-boot-starter3.2.0org.springframework.bootspring-boot-starter-freemarkermysqlmysql-connector-javaruntimecom.baomidoumybatis-plus-generator3.2.0
2.2、数据库构建与项目配置
使用Navicat创建mysql数据库 “vueblog”,创建数据表,SQL语句(自己懒得写,参考某大神的现成的SQL):
CREATE TABLE `m_user` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, `username` varchar(64) DEFAULT NULL, `avatar` varchar(255) DEFAULT NULL, `email` varchar(64) DEFAULT NULL, `password` varchar(64) DEFAULT NULL, `status` int(5) NOT NULL, `created` datetime DEFAULT NULL, `last_login` datetime DEFAULT NULL, PRIMARY KEY (`id`), KEY `UK_USERNAME` (`username`) USING BTREE ) ENGINE=InnoDB DEFAULT CHARSET=utf8; CREATE TABLE `m_blog` ( `id` bigint(20) NOT NULL AUTO_INCREMENT, `user_id` bigint(20) NOT NULL, `title` varchar(255) NOT NULL, `description` varchar(255) NOT NULL, `content` longtext, `created` datetime NOT NULL ON UPDATE CURRENT_TIMESTAMP, `status` tinyint(4) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB AUTO_INCREMENT=11 DEFAULT CHARSET=utf8mb4; INSERT INTO `vueblog`.`m_user` (`id`, `username`, `avatar`, `email`, `password`, `status`, `created`, `last_login`) VALUES ('1', 'test', 'https://image-1300566513.cos.ap-guangzhou.myqcloud.com/upload/images/5a9f48118166308daba8b6da7e466aab.jpg', NULL, '96e79218965eb72c92a549dd5a330112', '0', '2020-04-20 10:44:01', NULL);
在工程的application.properties中,配置数据源datasource与mybatis-plus:
server.port=8080 # DataSource Config spring.datasource.url=jdbc:mysql://localhost:3306/vueblog?useUnicode=true&useSSL=false&characterEncoding=utf8 spring.datasource.username=root spring.datasource.password=qixingchao spring.datasource.driver-class-name=com.mysql.jdbc.Driver mybatis-plus.mapper-locations=classpath*:/mapper/**Mapper.xml
2.3、导入、调整CodeGenerator源码
注意:数据源、包名信息一定要根据自己项目信息进行调整
package com.qxc; import com.baomidou.mybatisplus.core.exceptions.MybatisPlusException; import com.baomidou.mybatisplus.core.toolkit.StringPool; import com.baomidou.mybatisplus.core.toolkit.StringUtils; import com.baomidou.mybatisplus.generator.AutoGenerator; import com.baomidou.mybatisplus.generator.InjectionConfig; import com.baomidou.mybatisplus.generator.config.*; import com.baomidou.mybatisplus.generator.config.po.TableInfo; import com.baomidou.mybatisplus.generator.config.rules.NamingStrategy; import com.baomidou.mybatisplus.generator.engine.FreemarkerTemplateEngine; import java.util.ArrayList; import java.util.List; import java.util.Scanner; public class CodeGenerator { /** ** 读取控制台内容 **/ public static String scanner(String tip) { Scanner scanner = new Scanner(System.in); StringBuilder help = new StringBuilder(); help.append("请输入" + tip + ":"); System.out.println(help.toString()); if (scanner.hasNext()) { String ipt = scanner.next(); if (StringUtils.isNotEmpty(ipt)) { return ipt; } } throw new MybatisPlusException("请输入正确的" + tip + "!"); } public static void main(String[] args) { // 代码生成器 AutoGenerator mpg = new AutoGenerator(); // 全局配置 GlobalConfig gc = new GlobalConfig(); String projectPath = System.getProperty("user.dir"); gc.setOutputDir(projectPath + "/src/main/java"); gc.setAuthor("qixingchao"); gc.setOpen(false); gc.setServiceName("%sService"); mpg.setGlobalConfig(gc); // 数据源配置 DataSourceConfig dsc = new DataSourceConfig(); dsc.setUrl("jdbc:mysql://localhost:3306/vueblog?useUnicode=true&useSSL=false&characterEncoding=utf8&serverTimezone=UTC"); dsc.setDriverName("com.mysql.cj.jdbc.Driver"); dsc.setUsername("root"); dsc.setPassword("qixingchao"); mpg.setDataSource(dsc); // 包配置 PackageConfig pc = new PackageConfig(); pc.setModuleName(null); pc.setParent("com.qxc"); mpg.setPackageInfo(pc); // 自定义配置 InjectionConfig cfg = new InjectionConfig() { @Override public void initMap() { // to do nothing } }; // 如果模板引擎是 freemarker String templatePath = "/templates/mapper.xml.ftl"; // 如果模板引擎是 velocity // String templatePath = "/templates/mapper.xml.vm"; // 自定义输出配置 ListfocList = new ArrayList<>(); // 自定义配置会被优先输出 focList.add(new FileOutConfig(templatePath) { @Override public String outputFile(TableInfo tableInfo) { // 自定义输出文件名 , 如果你 Entity 设置了前后缀、此处注意 xml 的名称会跟着发生变化!! return projectPath + "/src/main/resources/mapper/" + "/" + tableInfo.getEntityName() + "Mapper" + StringPool.DOT_XML; } }); cfg.setFileOutConfigList(focList); mpg.setCfg(cfg); // 配置模板 TemplateConfig templateConfig = new TemplateConfig(); templateConfig.setXml(null); mpg.setTemplate(templateConfig); // 策略配置 StrategyConfig strategy = new StrategyConfig(); strategy.setNaming(NamingStrategy.underline_to_camel); strategy.setColumnNaming(NamingStrategy.underline_to_camel); strategy.setEntityLombokModel(true); strategy.setRestControllerStyle(true); strategy.setInclude(scanner("表名,多个英文逗号分割").split(",")); strategy.setControllerMappingHyphenStyle(true); strategy.setTablePrefix("m_"); mpg.setStrategy(strategy); mpg.setTemplateEngine(new FreemarkerTemplateEngine()); mpg.execute(); } }
2.4 执行CodeGenerator
右键CodeGenerator.java类 --> 选择"Run 'CodeGenerator.main()' "
IDEA底部弹出输入面板,手动输入数据库表名:
回车,自动生成基础代码:
2.5 代码测试
工程Application类增加自动扫描代码MapperScan:
package com.qxc; import org.mybatis.spring.annotation.MapperScan; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication @MapperScan("com.qxc.mapper") public class VueblogApplication { public static void main(String[] args) { SpringApplication.run(VueblogApplication.class, args); } }
UserController类里写接口测试方法:
package com.qxc.controller; import com.qxc.service.UserService; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.web.bind.annotation.GetMapping; import org.springframework.web.bind.annotation.PathVariable; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RestController; /** ** 前端控制器 ** * @author qixingchao * @since 2021-04-12 */ @RestController @RequestMapping("/user") public class UserController { @Autowired UserService userService; @GetMapping("/{id}") public Object getUserById(@PathVariable("id")long id){ return userService.getById(id); } }
通过IDEA启动工程,在浏览器输入与接口匹配的URL地址: