介绍：
Mybatis-Plus（简称MP）是一个 Mybatis 的增强工具，在 Mybatis 的基础上只做增强不做改变，为简化开发、提高效率而生。（摘自mybatis-plus官网）Mybatis虽然已经给我们提供了很大的方便，但它还是有不足之处，MP的存在就是为了稍稍弥补Mybatis的不足。在我们使用Mybatis时会发现，每当要写一个业务逻辑的时候都要在DAO层写一个方法，再对应一个SQL，即使是简单的条件查询、即使仅仅改变了一个条件都要在DAO层新增一个方法，针对这个问题，MP这样一个框架，一种集Mybatis与Hibernate的优点一起的框架。它提供了Hibernate的单表CURD操作的方便同时，又保留了Mybatis的特性。
本章只教大家怎么使用MybatisPlus，如果想深入了解底层是怎么实现的可以去官网下载源代码进行解读。
一、创建项目
这里就不一步一步来了，我直接给出创建后的项目结构，在本章的最后我会给出源码地址需要看效果的可以进行下载。
二、引入依赖
<?xml version="1.0" encoding="UTF-8"?><project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.chaoqi</groupId> <artifactId>springboot_mybatisplus</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>springboot_mybatisplus</name> <description>Demo project for Spring Boot</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.0.0.RELEASE</version> <relativePath/> </parent> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.mybatis.spring.boot</groupId> <artifactId>mybatis-spring-boot-starter</artifactId> <version>1.3.2</version> </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> <!--添加jsp依赖 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-tomcat</artifactId> </dependency> <dependency> <groupId>org.apache.tomcat.embed</groupId> <artifactId>tomcat-embed-jasper</artifactId> </dependency> <!-- SpringBoot - MyBatis 逆向工程 --> <dependency> <groupId>org.mybatis.generator</groupId> <artifactId>mybatis-generator-core</artifactId> <version>1.3.2</version> </dependency> <!-- MyBatis 通用 Mapper --> <dependency> <groupId>tk.mybatis</groupId> <artifactId>mapper-spring-boot-starter</artifactId> <version>1.1.4</version> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> <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>Generate MyBatis Artifacts</id> <goals> <goal>generate</goal> </goals> </execution> </executions> <dependencies> <dependency> <groupId>org.mybatis.generator</groupId> <artifactId>mybatis-generator-core</artifactId> <version>1.3.2</version> </dependency> <dependency> <groupId>tk.mybatis</groupId> <artifactId>mapper</artifactId> <version>3.5.0</version> </dependency> </dependencies> </plugin> </plugins> </build></project>
三、编辑application.yml
server: port: 8080spring: mvc: view: prefix: /WEB-INF/jsp/ suffix: .jsp datasource: url: jdbc:mysql://localhost:3306/test?characterEncoding=UTF-8&useUnicode=true&useSSL=false username: root password: 123456 driver-class-name: com.mysql.jdbc.Drivermybatis: mapper-locations: classpath:mapper/*.xml type-aliases-package: com.chaoqi.springboot_mybatisplus.domain
四、逆向生成pojo，mapper
创建generatorConfig.xml
<?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> <properties resource="application.yml"/> <classPathEntry location="D:/mysql/mysql-connector-java-5.1.46/mysql-connector-java-5.1.46.jar"/> <context id="Mysql" targetRuntime="MyBatis3Simple" defaultModelType="flat"> <property name="beginningDelimiter" value="`"/> <property name="endingDelimiter" value="`"/> <property name="javaFileEncoding" value="UTF-8"/> <plugin type="tk.mybatis.mapper.generator.MapperPlugin"> <property name="mappers" value="tk.mybatis.mapper.common.Mapper"/> </plugin> <!-- 注释 --> <commentGenerator> <!-- 是否生成注释代时间戳 --> <property name="suppressDate" value="true"/> <!-- 是否去除自动生成的注释 true：是 ： false:否 --> <property name="suppressAllComments" value="false"/> </commentGenerator> <!-- JDBC连接 --> <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://localhost:3306/test?characterEncoding=UTF-8" userId="root" password="123456"> </jdbcConnection> <!-- 生成实体类地址 --> <javaModelGenerator targetPackage="com.chaoqi.springboot_mybatisplus.dao.domain" targetProject="src/main/java"/> <!-- 生成mapper xml文件 --> <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources"/> <!-- 生成mapper xml对应Client--> <javaClientGenerator targetPackage="com.chaoqi.springboot_mybatisplus.dao.mapper" targetProject="src/main/java" type="XMLMAPPER"/> <!-- 配置表信息 --> <table tableName="%"> <!--mysql 配置--> <generatedKey column="id" sqlStatement="Mysql"/> <!--oracle 配置--> <!--<generatedKey column="id" sqlStatement="select SEQ_{1}.nextval from dual" identity="false" type="pre"/>--> </table> </context></generatorConfiguration>maven运行generator
生成完后的项目结构如下
五、整合mybatisplus
创建service接口以及service实现类
package com.chaoqi.springboot_mybatisplus.service;import com.chaoqi.springboot_mybatisplus.dao.domain.MusicInfo;import java.util.List;public interface MusicInfoService { public List<MusicInfo> getMusicInfo();}package com.chaoqi.springboot_mybatisplus.service.impl;import com.chaoqi.springboot_mybatisplus.dao.domain.MusicInfo;import com.chaoqi.springboot_mybatisplus.dao.mapper.MusicInfoMapper;import com.chaoqi.springboot_mybatisplus.service.MusicInfoService;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import java.util.List;@Servicepublic class MusicInfoServiceImpl implements MusicInfoService { @Autowired private MusicInfoMapper musicInfoMapper; @Override public List<MusicInfo> getMusicInfo() { List<MusicInfo> musicInfos = musicInfoMapper.selectAll(); return musicInfos; }}创建Controller
package com.chaoqi.springboot_mybatisplus.web;import com.chaoqi.springboot_mybatisplus.dao.domain.MusicInfo;import com.chaoqi.springboot_mybatisplus.service.MusicInfoService;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RestController;import java.util.List;@RestController@RequestMapping(value = "/music")public class MusicInfoController { @Autowired private MusicInfoService musicInfoService; @RequestMapping("/showMusic") public List<MusicInfo> getMusicInfo() { List<MusicInfo> musicInfo1 = musicInfoService.getMusicInfo(); return musicInfo1; }}这里我的mapper并不要写sql，一些简单的sqlmybatiplus都给封装好了，节省了许多开发时间，如果是一些复杂的sql，也可以通过写原生sql来实现，在我的第二篇博客中有讲到springboot+springmvc+mybatis项目整合
运行SpringbootMybatisplusApplication主函数
package com.chaoqi.springboot_mybatisplus;import org.mybatis.spring.annotation.MapperScan;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;@SpringBootApplication@MapperScan("com.chaoqi.springboot_mybatisplus.dao.mapper")public class SpringbootMybatisplusApplication { public static void main(String[] args) { SpringApplication.run(SpringbootMybatisplusApplication.class, args); }}查看数据库
下面给出mybatisplus封装的一些方法，这些方法具体怎么使用，感兴趣的小伙伴可以查看下源代码，mybatisplus还有一个强大的分页功能，如果有兴趣也可以去这里学习
（源码下载地址）
最后谢谢大家的观看，写博客经验不足，写得不好请见谅