springboot集成mybatisplus的方法

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。（）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: 8080

spring:
 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.driver

mybatis:
 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;

@service
public 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

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