[SpringBoot]在Springboot中接入Mybatis-plus

加入依赖

pom.xml

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<dependency>
    <groupId>com.baomidou</groupId>
    <artifactId>mybatis-plus-boot-starter</artifactId>
    <version>3.1.0</version>
</dependency>

配置 MapperScan 注解

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@SpringBootApplication
@MapperScan("com.your.package.**.mapper")
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(BootdoApplication.class, args);
    }

}

配置application.yml(以yml文件为例)

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mybatis:
  configuration:
    map-underscore-to-camel-case: true
  mapper-locations: classpath*:/mapper/**/*.xml
  typeAliasesPackage: com.your.package.**.entity

数据源配置

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spring:
  datasource:
    type: com.alibaba.druid.pool.DruidDataSource
    driverClassName: com.mysql.jdbc.Driver
    url: jdbc:mysql://127.0.01:3306/demo?useUnicode=true&characterEncoding=utf8
    username: root
    password: root
    initialSize: 1
    minIdle: 3
    maxActive: 20
    maxWait: 60000
    timeBetweenEvictionRunsMillis: 60000
    minEvictableIdleTimeMillis: 30000
    validationQuery: select 'x'
    testWhileIdle: true
    testOnBorrow: false
    testOnReturn: false
    poolPreparedStatements: true
    maxPoolPreparedStatementPerConnectionSize: 20
    filters: stat,wall,slf4j
    connectionProperties: druid.stat.mergeSql=true;druid.stat.slowSqlMillis=5000

创建entity

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package com.your.package.**.entity;

import io.swagger.annotations.ApiModel;
import lombok.Data;
import lombok.EqualsAndHashCode;
import lombok.experimental.Accessors;

import java.io.Serializable;

@Data
@EqualsAndHashCode(callSuper = false)
@Accessors(chain = true)
public class Demo implements Serializable {

    private static final long serialVersionUID = 1L;

    @TableId(value = "classId", type = IdType.AUTO)
    private Long classId;

    @TableField("className")
    private String className;
}

注意:这里使用了@Data注解来简化代码，否则要完整书写getter、setter类方法。
你可以增加依赖lombok来使用它

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<dependency>
    <groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <optional>true</optional>
</dependency>

另外如果你使用Idea则还需要Lombok Plugin插件，你才能正常使用getter、setter代码提示及正常编译。

创建mapper

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package com.your.package.**.mapper;

import com.your.package.**.entity.Demo;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import org.apache.ibatis.annotations.Mapper;

@Mapper
public interface DemoMapper extends BaseMapper<Demo> {}

创建service

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package com.your.package.**.service;

import com.your.package.**.entity.Demo;
import com.baomidou.mybatisplus.extension.service.IService;

public interface DemoService extends IService<Demo> {}

创建serviceImpl

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package com.your.package.**.service.impl;

import com.your.package.**.entity.Demo;
import com.your.package.**.mapper.DemoMapper;
import com.your.package.**.service.DemoService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.springframework.stereotype.Service;

@Service
public class DemoServiceImpl extends ServiceImpl<DemoMapper, Demo> implements DemoService {}

创建mapper.xml

在resources/maaper目录下

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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.your.package.**.mapper.DemoMapper">
	<!-- 通用查询映射结果 -->
    <resultMap id="BaseResultMap" type="com.your.package.**.entity.Demo">
        <id column="classId" property="classId" />
        <result column="className" property="className" />
    </resultMap>

    <!-- 通用查询结果列 -->
    <sql id="Base_Column_List">
        contentId, className
    </sql>

</mapper>

在controller中使用

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package com.your.package.**.controller;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.bind.annotation.RestController;

@RestController
@RequestMapping("/api")
public class DemoController {
    private final Logger logger = LoggerFactory.getLogger(DemoController.class);
    @Autowired
    public DemoService iDemoService;

	@RequestMapping("/demo")
	@ResponseBody
	public Page demo(
	@RequestParam(name = "page", defaultValue = "1") int page,
	@RequestParam(name = "size", defaultValue = "20") int size){
	    QueryWrapper<Demo> queryWrapper = new QueryWrapper<>();
	    queryWrapper.eq("classId",1);
	    Page ipage = new Page(page,size);
	    iDemoService.page(ipage,queryWrapper);
	    return ipage;
	}
}

结束