<version>5.1.45</version>

</dependency>

<dependency>

<groupId>com.baomidou</groupId>

<artifactId>mybatis-plus-boot-starter</artifactId>

<version>3.4.0</version>

</dependency>

2.2 在 application.yml 进行配置数据源

2.2.1 新建 applicaiton.yml`

环境隔离

spring:

profiles:

active: dev

server:

compression:

请求 gzip 压缩

enabled: true

mime-types: text/html,text/xml,text/plain,text/css,text/javascript,application/javascript,application/json,application/xml

min-response-size: 1024

application:

name: edu-front-web

模板视图 thymeleaf

thymeleaf:

cache: false

prefix: classpath:/templates/

mode: HTML

encoding: UTF-8

json 的转换配置

jackson:

date-format: yyyy-MM-dd HH:mm:ss

time-zone: GMT+8

locale: zh_CN

generator:

write-numbers-as-strings: true

write-bigdecimal-as-plain: true

##mybatis 的原生态支持

mybatis-plus:

mapper-locations: classpath*:/mapper/*.xml

type-aliases-package: com.example.entity

#logging:

level:

root: debug

2.2.2 新建 applicaiton-dev.yml`

数据源的配置

spring:

datasource:

type: com.zaxxer.hikari.HikariDataSource

driver-class-name: com.mysql.jdbc.Driver

url: jdbc:mysql://127.0.0.1:3306/test?serverTimezone=GMT%2b8&useUnicode=true&characterEncoding=utf-8&useSSL=false

username: root

password: 123456

hikari:

connection-timeout: 60000

validation-timeout: 3000

idle-timeout: 60000

login-timeout: 5

max-lifetime: 60000

maximum-pool-size: 30

minimum-idle: 10

read-only: false

2.2.3 新建数据库和表

/*

Navicat MySQL Data Transfer

Source Server : localhost_3306

Source Server Version : 50635

Source Host : localhost:3306

Source Database : test

Target Server Type : MYSQL

Target Server Version : 50635

File Encoding : 65001

Date: 2021-07-23 10:19:25

*/

SET FOREIGN_KEY_CHECKS=0;

-- Table structure for user

DROP TABLE IF EXISTS user;

CREATE TABLE user (

id int(11) NOT NULL AUTO_INCREMENT,

nickname varchar(255) CHARACTER SET utf8mb4 DEFAULT NULL COMMENT '用户名',

password varchar(255) CHARACTER SET utf8mb4 DEFAULT NULL COMMENT '密码',

age int(11) DEFAULT NULL COMMENT '年龄',

male int(11) DEFAULT NULL COMMENT '性别',

PRIMARY KEY (id)

) ENGINE=InnoDB DEFAULT CHARSET=latin1;

2.2.4 新建实体

package com.example.entity;

import com.baomidou.mybatisplus.annotation.IdType;

import com.baomidou.mybatisplus.annotation.TableId;

import com.baomidou.mybatisplus.annotation.TableName;

import io.swagger.annotations.ApiModel;

import io.swagger.annotations.ApiModelProperty;

import lombok.AllArgsConstructor;

import lombok.Data;

import lombok.NoArgsConstructor;

import lombok.ToString;

import lombok.experimental.Accessors;

@Data // getter/setter

@ToString // toString

@AllArgsConstructor // 有参构造函数

@NoArgsConstructor // 无参构造函数

@TableName("user")

@Accessors(chain = true)

@ApiModel(description = "用户实体")

public class User {

// 用户编号

@TableId(type = IdType.AUTO)

@ApiModelProperty(value = "用户编号", required = true)

private Integer id;

// 用户昵称

@ApiModelProperty(value = "用户昵称", required = true)

private String nickname;

// 用户密码

@ApiModelProperty(value = "用户密码", required = true)

private String password;

// 用户年龄

@ApiModelProperty(value = "用户年龄", required = true)

private Integer age;

// 用户性别 0 女 1 男 2 保密

@ApiModelProperty(value = "用户性别", required = true)

private Integer male;

}

2.2.5 新建 mapper

package com.example.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;

import com.example.entity.User;

/**

• @Auther: 长颈鹿

• @Date: 2021/07/23/10:16

• @Description:

*/

public interface UserMapper extends BaseMapper<User> {

}

2.2.6 mybatis 和 spring 融合

在启动类上增加@MapperScan("com.kuangstudy.mapper")

package com.example;

import org.mybatis.spring.annotation.MapperScan;

import org.springframework.boot.SpringApplication;

import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication

@MapperScan

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("com.example.mapper")

public class StudyBootsMybatisApplication {

public static void main(String[] args) {

SpringApplication.run(StudyBootsMybatisApplication.class, args);

}

}

2.2.7 定义户 Service 接口和实现类

package com.example.service;

import com.baomidou.mybatisplus.extension.service.IService;

import com.example.entity.User;

/**

• @Auther: 长颈鹿

• @Date: 2021/07/23/10:22

• @Description:

*/

public interface UserService extends IService<User> {

}

package com.example.service;

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;

import com.example.entity.User;

import com.example.mapper.UserMapper;

/**

• @Auther: 长颈鹿

• @Date: 2021/07/23/10:23

• @Description:

*/

@Service

public class UserServiceImpl extends ServiceImpl<UserMapper, User> implements UserService {

}

2.2.8 测试用例

package com.example;

import com.example.entity.User;

import com.example.service.UserService;

import org.junit.jupiter.api.Test;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.boot.test.context.SpringBootTest;

@SpringBootTest

class StudyBootsMybatisApplicationTests {

@Autowired

private UserService userService;

@Test

public void saveUser(){

User user = new User();

user.setId(1);

user.setNickname("yykkxxxx");

user.setPassword("1121455");

user.setAge(34);

user.setMale(1);

userService.saveOrUpdate(user);

}

}

3、基于 xml 的原生态的 mybatis 的支持

3.1 在 application.yml 增加支持 xml 的方式

##mybatis 的原生态支持

mybatis-plus:

mapper-locations: classpath*:/mapper/*.xml

type-aliases-package: com.kuangstudy.entity

3.2 在 UserMapper 定义方法