SpringBoot整合Mybatis

创建项目

使用Intellij IDEA快速创建SpringBoot项目

image-20230104172223592

选择springboot版本号,并且勾选MyBatis与MySQL驱动

image-20230104183449780

配置MyBatis

SpringBoot项目配置MyBatis特别简单,只需要在配置文件中填写所需的连接信息就行了

application.yml配置文件中添加连接信息

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spring:
datasource:
driver-class-name: com.mysql.cj.jdbc.Driver
url: jdbc:mysql://localhost:3306/test
username: manager
password: mk123456

这样就配置完成了,是不是非常简单

创建实体类

创建一个用户装载数据库中的表的数据的实体类

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package com.example.main;

import java.util.Date;

/**
* @author makun
* @project spring-boot
* @description 用户实体类
* @date 2023/01/04 18:45:13
* version 1.0
*/
public class User {
private Integer id;
private String name;
private String gender;
private Integer age;
private String phone;
private Date birthday;
private Double balance;

public User() {
}

public User(Integer id, String name, String gender, Integer age, String phone, Date birthday, Double balance) {
this.id = id;
this.name = name;
this.gender = gender;
this.age = age;
this.phone = phone;
this.birthday = birthday;
this.balance = balance;
}

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

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 String getGender() {
return gender;
}

public void setGender(String gender) {
this.gender = gender;
}

public Integer getAge() {
return age;
}

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

public String getPhone() {
return phone;
}

public void setPhone(String phone) {
this.phone = phone;
}

public Date getBirthday() {
return birthday;
}

public void setBirthday(Date birthday) {
this.birthday = birthday;
}

public Double getBalance() {
return balance;
}

public void setBalance(Double balance) {
this.balance = balance;
}
}

创建持久层访问类

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package com.example.dao;

import com.example.main.User;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;

import java.util.List;

/**
* @author makun
* @project spring-boot
* @description 用户持久层访问
* @date 2023/01/04 18:55:06
* version 1.0
*/

// 让Mybatis知道这是一个持久层访问的接口,并且交给SpringBoot管理
@Mapper
public interface UserDao {
@Select("select * from t_user")
List<User> queryAll();
}

创建服务类

创建服务接口

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package com.example.service;

import com.example.main.User;
import java.util.List;

/**
* @author makun
* @project spring-boot
* @description 用户服务接口
* @date 2023/01/04 18:51:37
* version 1.0
*/

public interface UserService {
List<User> getAllUsers();
}

实现服务类接口

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package com.example.service.impl;

import com.example.dao.UserDao;
import com.example.main.User;
import com.example.service.UserService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import java.util.List;

/**
* @author makun
* @project spring-boot
* @description 用户服务类接口实现
* @date 2023/01/04 18:53:40
* version 1.0
*/
@Service
public class UserServiceImpl implements UserService {
@Autowired
private UserDao userDao;

@Override
public List<User> getAllUsers() {
return userDao.queryAll();
}
}

创建持久层访问接口

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package com.example.dao;

import com.example.main.User;
import org.apache.ibatis.annotations.Mapper;
import org.apache.ibatis.annotations.Select;
import java.util.List;

/**
* @author makun
* @project spring-boot
* @description 用户持久层访问
* @date 2023/01/04 18:55:06
* version 1.0
*/

// 让Mybatis知道这是一个持久层访问的接口,并且交给SpringBoot管理
@Mapper
public interface UserDao {
@Select("select * from t_user")
List<User> queryAll();
}

编写测试代码

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package com.example.service;

import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;

/**
* @author makun
* @project spring-boot
* @description
* @date 2023/01/04 19:00:17
* version 1.0
*/
@SpringBootTest
class UserServiceTest {
@Autowired
private UserService userService;
@Test
void getAllUsers() {
System.out.println(userService.getAllUsers());
}
}

如果输出正确,表示配置成功