springboot整合mybatis入门案例

概述

建表

创建spring boot工程

创建susert实体类

编写mapper接口

编写mapper配置文件

编写Service接口以及实现类

编写Controller测试

在application.properties配置数据库等信息

运行测试

---

概述

我们开发项目时经常用到spring boot框架，而spring boot框架经常与第三方框架整合。因此学习如何整合第三方框架变得很重要。本篇介绍spring boot如何整合mybatis。接下来我们就一起来看吧！

建表

创建springboot工程

使用idea创建spring boot工程并加入相关依赖

        <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>2.2.2</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>

创建user实体类

package com.yss.entity;

/**
 * @author yss
 * @date 22022-05-08
 */
public class User {
    private Integer id;
    private String name;
    private Integer age;

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}

编写mapper接口

package com.yss.mapper;

import com.yss.entity.User;
import org.springframework.stereotype.Repository;

/**
 * @author yss
 * @date 200-05-08
 */
@Repository
public interface UserMapper {
    //添加一个根据id查询对象的方法
    User selectUserById(Integer id);
}

编写mapper配置文件

<?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.yss.mapper.UserMapper">
    <select id="selectUserById" resultType="com.yss.entity.User">
        SELECT id, name, age
        FROM user
        where id = #{id}
    </select>
</mapper>

mapper文件的位置

1.  编写service接口及其实现类

package com.yss.service;

import com.yss.entity.User;

/**
 * @author yss
 * @date 2022-05-08
 */
public interface UserService {
    User queryUserById(Integer id);
}

package com.yss.service;

import com.yss.entity.User;
import com.yss.mapper.UserMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

/**
 * @author yss
 * @date 2022-05-08
 */

@Service
public class UserServiceImpl implements UserService{
    @Autowired
    private UserMapper userMapper;

    @Override
    public User queryUserById(Integer id) {
        return userMapper.selectUserById(id);
    }
}

编写controller测试

package com.yss.controller;

import com.yss.entity.User;
import com.yss.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

/**
 * @author yss
 * @date 2022-05-08
 */
@RestController
public class UserController {
    @Autowired
    private UserService userService;

    @RequestMapping("/getUser")
    public String getUser(Integer id){
        User user = userService.queryUserById(id);
        return user.toString();
    }
}

在application.yaml文件配置数据库信息

spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    username: root
    password: 123456
    url: jdbc:mysql://localhost:3306/jdbcstudy?useUnicode=true&characterEncoding=utf-8&useSSL=true&serverTimezone=UTC
mybatis:
  #指定映射文件的路径
  mapper-locations: classpath:mapping/*.xml
  type-aliases-package: com.yss.entity
  #添加日志输出
  configuration:
    log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

运行测试

 如果要看日志输出的话，就配置日志信息，如下图所示。