Mybatis（1）-入门使用

Mybatis-入门使用

①导入MyBatis依赖（此处为maven项目）

<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
<dependency>
     <groupId>org.mybatis</groupId>
     <artifactId>mybatis</artifactId>
     <version>3.5.6</version>
 </dependency>

②导入JDBC驱动包依赖（此处为mysql-connector-java）

<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.25</version>
</dependency>

③新建mybatis配置文件（此处为 mybatis-config.xml）

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://127.0.0.1:3306/sakila"/>
                <property name="username" value="root"/>
                <property name="password" value="root"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <mapper resource="mybatis/ActorMapper.xml"/>
    </mappers>
</configuration>

④新建mapper配置文件及mapper接口

mybatis/ActorMapper.xml

<?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.hs.mybatis.mapper.ActorMapper">

    <resultMap id="actorResultMap" type="com.hs.mybatis.bean.Actor">
        <id column="actor_id" property="actorId"/>
        <result column="first_name" property="firstName"/>
        <result column="last_name" property="lastName"/>
    </resultMap>

    <select id="selectOneActor" resultMap="actorResultMap">
        select actor_id, first_name,last_name from actor where actor_id = #{actorId}
    </select>
</mapper>

com.hs.mybatis.mapper.ActorMapper.java

package com.hs.mybatis.mapper;

import com.hs.mybatis.bean.Actor;
import org.apache.ibatis.annotations.Mapper;

//@Mapper
public interface ActorMapper {

    Actor selectOneActor(int actorId);
}

对应bean

package com.hs.mybatis.bean;

public class Actor {
    private int actorId;
    private String firstName;
    private String lastName;

    public int getActorId() {
        return actorId;
    }

    public void setActorId(int actorId) {
        this.actorId = actorId;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    @Override
    public String toString() {
        return "Actor{" +
                "actorId=" + actorId +
                ", firstName='" + firstName + '\'' +
                ", lastName='" + lastName + '\'' +
                '}';
    }
}

⑤测试

com.hs.mybatis.Main.java

package com.hs.mybatis;

import com.hs.mybatis.bean.Actor;
import com.hs.mybatis.mapper.ActorMapper;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;

import java.io.IOException;
import java.io.InputStream;

public class Main {
    public static void main(String[] args) {
        String resource = "mybatis-config.xml";
        SqlSession session = null;
        try {
            InputStream inputStream = Resources.getResourceAsStream(resource);
            SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
            System.out.println(sqlSessionFactory);
            session = sqlSessionFactory.openSession();
            ActorMapper actorMapper = session.getMapper(ActorMapper.class);
            Actor actor = actorMapper.selectOneActor(1);
            System.out.println(actor);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (session != null) {
                session.close();
            }
        }

    }
}

Mybatis官网：
https://mybatis.org/mybatis-3/zh/getting-started.html