六步SpringBoot整合Mybatis

SpringBoot整合Mybatis

1 导入依赖

导入的依赖有：

• mybatis-spring-boot-starter
• spring-boot-starter-jdbc
• spring-boot-starter-web
• mysql-connector-java

具体如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" 
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 
                             https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.5.6</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.xzzlx</groupId>
    <artifactId>springboot-05-mybatis</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>springboot-05-mybatis</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>11</java.version>
    </properties>
    <dependencies>
        <!-- mybatis-spring-boot-starter -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.2.0</version>
        </dependency>
        <!-- jdbc -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <!-- web -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- mysql -->
        <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>
    </dependencies>

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

</project>

2 修改resources中配置文件

修改application.yaml

spring:
    datasource:
        url: jdbc:mysql://192.168.18.176:3306/win_database01?useSSL=true&useUnicode=true&
        characterEncoding=UTF-8&serverTimeZone=Aisa/Shanghai
        driver-class-name: com.mysql.cj.jdbc.Driver
        username: root
        password: 123456
---
mybatis:
    mapper-locations: classpath:mybatis/mapper/*.xml
    type-aliases-package: com.xzzlx.pojo

核心：

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

type-aliases-package: com.xzzlx.pojo

3 连接数据库创建实体类

创建pojo包，新建User类

package com.xzzlx.pojo;


public class User {

  private Long id;
  private String name;
  private String password;


  public User() {
  }

  public User(Long id, String name, String password) {
    this.id = id;
    this.name = name;
    this.password = password;
  }

  public Long getId() {
    return id;
  }

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


  public String getName() {
    return name;
  }

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


  public String getPassword() {
    return password;
  }

  public void setPassword(String password) {
    this.password = password;
  }

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

4 创建mapper文件

创建接口

package com.xzzlx.mapper;

import com.xzzlx.pojo.User;
import org.apache.ibatis.annotations.Mapper;
import org.springframework.stereotype.Repository;
import org.springframework.web.bind.annotation.PathVariable;

import java.util.List;


// 表明这是一个mybatis的mapper类

@Mapper
@Repository
public interface UserMapper {

    /**
     * 返回全部用户
     * @return 用户列表
     */
    List<User> queryUserList();

    /**
     * 查找某个用户
     * @param id 用户id
     * @return 用户对象
     */
    User queryUserById(@PathVariable("id") Long id);

    /**
     * 增加用户
     * @param user 用户对象
     * @return 操作是否成功 0 失败  1 成功
     */
    Long addUser(User user);

    /**
     * 修改用户
     * @param user 用户对象
     * @return 操作是否成功 0 失败  1 成功
     */
    Long updateUser(User user);

    /**
     * 删除用户
     * @param id 用户id
     * @return 操作是否成功 0 失败  1 成功
     */
    Long deleteUser(@PathVariable("id") Long id);

}

5 创建xml文件

在resources文件夹下创建mybatis文件，然后在mybatis创建mapper文件，在这里创建UserMapper.xml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.xzzlx.mapper.UserMapper">

    <select id="queryUserList" resultType="user">
        select * from win_database01.user
    </select>

    <select id="queryUserById" parameterType="_Long" resultType="user">
        select * from win_database01.user where id = #{id}
    </select>

    <insert id="addUser" parameterType="user">
        insert into win_database01.user (id, name, password) VALUES (#{id}, #{name}, #{password})
    </insert>

    <update id="updateUser" parameterType="user">
        update win_database01.user set name = #{name}, password = #{password} where id = #{id}
    </update>

    <delete id="deleteUser" parameterType="_Long">
        delete from win_database01.user where id = #{id}
    </delete>
</mapper>

6 创建controller层

创建UserController类

package com.xzzlx.controller;

import com.xzzlx.mapper.UserMapper;
import com.xzzlx.pojo.User;
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.RestController;

import java.util.List;

@RestController
public class UserController {

    @Autowired
    private UserMapper userMapper;

    @GetMapping("/queryUserList")
    public List<User> queryUserList(){
        List<User> users = userMapper.queryUserList();
        for (User user : users) {
            System.out.println(user);
        }
        return users;
    }

    @GetMapping("/queryUserById/{id}")
    public User queryUserById(@PathVariable("id") Long id){
        User user = userMapper.queryUserById(id);
        System.out.println(user);
        return user;
    }

    @GetMapping("/addUser")
    public String addUser(User user){
        userMapper.addUser(new User(2L, "邓局", "123456"));
        return "新增成功";
    }

    @GetMapping("/updateUser")
    public String updateUser(User user){
        userMapper.updateUser(new User(2L, "邓局", "18888886"));
        return "修改成功";
    }

    @GetMapping("/deleteUser/{id}")
    public String deleteUser(@PathVariable("id") Long id){
        userMapper.deleteUser(2L);
        return "删除成功";
    }

}

7 启动SpringBoot项目测试

在SpringBoot项目入口启动测试

package com.xzzlx;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

// @MapperScan("com.xzzlx.mapper") 自动扫描该包下所有的接口

@SpringBootApplication
public class Springboot05MybatisApplication {

    public static void main(String[] args) {
        SpringApplication.run(Springboot05MybatisApplication.class, args);
    }

}

以上就是SpringBoot整合Mybatis的demo，有问题可以留言一起讨论，谢谢~