SpringBoot快速內建MyBatis-plus---(第一篇)

SpringBoot整合Mybatis-plus

git項目位址 完整版

1.建立項目

首先我們需要建立一個SpringBoot建立,我使用的是maven建構SpringBoot項目.在這裡我們就不貼圖了

2.導入SpringBoot以及其他的依賴

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>

        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.3.1</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.22</version>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.16</version>
        </dependency>
    </dependencies>

<build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>

        </plugins>
        <!--生産xml-->
        <!-- 如果不添加此節點mybatis的mapper.xml檔案都會被漏掉。 -->
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.yml</include>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.yml</include>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                    <include>**/*.html</include>
                    <include>**/*.css</include>
                    <include>**/*.js</include>
                    <include>**/*.*</include>
                </includes>
                <filtering>false</filtering>
            </resource>
        </resources>
    </build>

           

​ 注:我用得mysql為 5.7版本的你們可根據自身版本挑選依賴

2.1建立SpringBoot啟動類

public static void main(String[] args) throws Exception{
        Long s1 = System.currentTimeMillis();
        ConfigurableApplicationContext application = SpringApplication.run(MybatisApplication.class, args);
        Long s2 = System.currentTimeMillis();

        Environment env = application.getEnvironment();
        String ip = InetAddress.getLocalHost().getHostAddress();
        String port = env.getProperty("server.port");
        String path = env.getProperty("server.servlet.context-path");

        System.out.println("=======================================>");
        System.out.println("啟動耗時=======>"+(s2-s1));
        System.out.println("Local:http://localhost:" + port + path);
        System.out.println("serve start-up success");
        System.out.println("=======================================>");
    }
           

2.2建立yml檔案

#配置端口号
server:
  port: 8085


#配置資料庫連接配接
spring:
  datasource:
#配置的資料源為druid
    type: com.alibaba.druid.pool.DruidDataSource
    driver-class-name: com.mysql.jdbc.Driver
    url: jdbc:mysql://localhost:3306/gxhserve?UseSSL=true&characterEncoding=UTF-8&UseUnicode=true
    username: root
    password: 123456



#配置MybatisPlus
mybatis-plus:
  global-config:
    #關閉啟動MybatisPlus自帶的banner圖
    banner: false
  #配置掃描xml資源路徑
  mapper-locations: classpath*:com/gxh/modules/**/xml/*Mapper.xml
  #自動駝峰映射
  configuration:
    map-underscore-to-camel-case: true
           

2.3 MybatisPlusConfig

/***
 * @author gxh
 * @date 2021-8-21
 */

@Configuration
@MapperScan(value = {"com.gxh.modules.**.mapper*"})
public class MybatisPlusConfig {

    /**
     *  分頁插件  MybatisPlus提供的分頁
     */
    @Bean
    public PaginationInterceptor paginationInterceptor() {
        // 設定sql的limit為無限制，預設是500
        return new PaginationInterceptor().setLimit(-1);
    }

}
           

貼出我的目錄結構

測試運作

1.建立一張表

id	username	password
1	admin	123456

2.建立實體

package com.gxh.modules.entity;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.Data;
import java.io.Serializable;
import java.util.Objects;

@TableName("sys_user")//mybatisPlus 注解:映射表名
@Data// lombok代碼簡化注解,包裝Get/Set/構造器
public class SysUser implements Serializable {

    private Integer id;

    private String username;

    private String password;


    /**
     * 重寫父類Object 提供的 toString方法,友善測試
     * @return
     */
    @Override
    public String toString() {
        return "SysUser{" +
                "id='" + id + '\'' +
                ", username='" + username + '\'' +
                ", password='" + password + '\'' +
                '}';
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        SysUser sysUser = (SysUser) o;
        return Objects.equals(id, sysUser.id) &&
                Objects.equals(username, sysUser.username) &&
                Objects.equals(password, sysUser.password);
    }

    @Override
    public int hashCode() {
        return Objects.hash(id, username, password);
    }
}
           

3.建立Dao(Mapper)層接口---------------映射xml檔案

package com.gxh.modules.mapper;
import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.gxh.modules.entity.SysUser;

//                                              BaseMapper 是MyBatisPlus提供
public interface SysUserMapper extends BaseMapper<SysUser> {
}

           

<?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">
<!--引用指向的mapper接口-->
<mapper namespace="com.gxh.modules.mapper.SysUserMapper">

</mapper>
           

4建立業務層及其實作類

package com.gxh.modules.service;
import com.baomidou.mybatisplus.extension.service.IService;
import com.gxh.modules.entity.SysUser;

public interface ISysUserService extends IService<SysUser> {
}
           

package com.gxh.modules.service.impl;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.gxh.modules.entity.SysUser;
import com.gxh.modules.mapper.SysUserMapper;
import com.gxh.modules.service.ISysUserService;
import lombok.RequiredArgsConstructor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;


@Service
//lombok 提供的注解簡化,  簡化了多個 @Autowired / @Resource
@RequiredArgsConstructor(onConstructor = @__(@Autowired))
public class SysUserServiceImpl
        extends ServiceImpl<SysUserMapper, SysUser>
        implements ISysUserService {

    //切記使用lombok 注入方式,必須private final 修飾,否則引起注入空指針
    private final SysUserMapper sysUserMapper;
}
           

5建立控制器并測試執行

package com.gxh.modules.controller;
import com.gxh.modules.entity.SysUser;
import com.gxh.modules.service.ISysUserService;
import lombok.RequiredArgsConstructor;
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;
import javax.websocket.server.PathParam;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@RestController
@RequestMapping("/sys/user")
//lombok 提供的注解簡化,  簡化了多個 @Autowired / @Resource
@RequiredArgsConstructor(onConstructor = @__(@Autowired))
public class SysUserController {

    //切記使用lombok 注入方式,必須private final 修飾,否則引起注入空指針
    private final ISysUserService sysUserService;


    @GetMapping("/{id}")
    public Map<String,Object> queryUserById(@PathVariable("id") Integer id){
        Map<String,Object> infoMap = new HashMap<>();
        SysUser sysUser = this.sysUserService.getById(id);
        infoMap.put("user",sysUser);
        return infoMap;
    }

    @GetMapping("/list")
    public Map<String,Object> userList(){
        Map<String,Object> infoMap = new HashMap<>();
        List<SysUser> users = this.sysUserService.list();
        infoMap.put("userList",users);
        return infoMap;
    }
}
           

測試圖示

最終工程結構

到此結束,以上就是SpringBoot和mybatis-plus的整合過程,關于其中的一些實戰開發中的用法下期在講解

SpringBoot快速內建MyBatis-plus—(第二篇)