MyBatis 的前身叫 iBatis，本是 apache 的一个开源项目， 2010 年这个项目由 apache Software foundation 迁移到了 GOOGLE code，并且改名为 MyBatis。MyBatis 是支持普通 SQL 查询，存储过程和高级映射的优秀持久层框架。MyBatis 消除了几乎所有的 JDBC 代码和参 数的手工设置以及结果集的检索。MyBatis 使用简单的 XML 或注解用于配置和原始映射， 将接口和 Java 的 POJOs（Plan Old Java Objects，普通的 Java 对象）映射成数据库中的记录。

<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.mybatis</groupId>
    <artifactId>mybatics</artifactId>
    <version>0.0.1-sNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.0.RELEASE</version>
        <relativePath /> <!-- lookup parent From reposITory -->
    </parent>

    <proPErties>
        <!-- 声明项目配置依赖编码格式为 utf-8 -->
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <fastjson.version>1.2.24</fastjson.version>
    </properties>

    <dependencies>

        <!--Spring Data Jpa依赖 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>

        <!--MySQL数据库驱动 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
            <version>8.0.13</version><!--$NO-MVN-MAN-VER$ -->
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>

        <!--mybatis -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.0</version>
        </dependency>

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid</artifactId>
            <version>1.1.10</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

server.port =8089

spring.datasource.url=jdbc:mysql://localhost:3306/springbootdb?serverTimezone=UTC&autoReconnect=true
spring.datasource.username=root
spring.datasource.password=admin
spring.jpa.hibernate.ddl-auto=create-drop
##spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

mybatis.mapper-locations=classpath:mappers/*.xml
mybatis.type-aliases-package=com.tszr.mybatis.mapper
mybatis.configuration.map-underscore-to-camel-case=true
spring.jpa.database=MySQL
spring.jpa.database-platform=org.hibernate.dialect.MySQL5InnoDBDialect
spring.jpa.show-sql=true

package com.tszr.mybatis.entity;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table(name = "user")
public class User {
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Integer id;// 编号
    
    @Column(name = "name", unique = true, nullable = false, length = 64)
    private String name;// 用户名
    
     @Column(name = "password", nullable = false, length = 64)
    private String password;// 密码

    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 getPassword() {
        return password;
    }

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

package com.tszr.mybatis.mapper;

import java.util.List;

import org.apache.ibatis.annotations.Mapper;

import com.tszr.mybatis.entity.User;

@Mapper//指定这是一个操作数据库的mapper
public interface UserMapper {
    List<User> findAll();
    int addUser(User user);
}

package com.tszr.mybatis.servies;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

import com.tszr.mybatis.entity.User;
import com.tszr.mybatis.mapper.UserMapper;

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

    public List<User> findAll() {
        return userMapper.findAll();
    }

    public int addUser(User user) {
        return userMapper.addUser(user);
    }
}

package com.tszr.mybatis.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;

import com.tszr.mybatis.entity.User;
import com.tszr.mybatis.servies.UserService;

@RestController
@RequestMapping("/user")
public class UserController {
    @Autowired
    private UserService userService;

    @RequestMapping("/findAll")
    public List<User> findAll() {
        return userService.findAll();
    }

    @PostMapping("/add")
    public String add(@RequestBody User user) {
        System.out.println("******************");
        System.out.println(user.getName());
        int i = userService.addUser(user);
        if (i > 0) {
            return "success";
        }
        return "fail";
    }
}

<?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.tszr.mybatis.mapper.UserMapper">
    <resultMap id="UserResult" type="com.tszr.mybatis.entity.User">
        <id column="id" property="id" ></id>
        <result column="name" property="name" ></result>
        <result column="password" property="password" ></result>
    </resultMap>
    <select id="findAll" resultMap="UserResult">
        SELECT * From user
    </select>
    <insert id="addUser" parameterType="com.tszr.mybatis.entity.User">
        insert into user (name,password) values (#{name},#{password});
    </insert>
</mapper>

package com.tszr.mybatis;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

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