一、配置mybatis

配置和使用mybatis

导入jar包

<!-- https://mvnrepository.com/artifact/org.mybatis/mybatis -->
<dependency>
  <groupId>org.mybatis</groupId>
  <artifactId>mybatis</artifactId>
  <version>3.4.6</version>
</dependency>

<!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
<dependency>
  <groupId>mysql</groupId>
  <artifactId>mysql-connector-java</artifactId>
  <version>8.0.13</version>
</dependency>

配置核心配置文件

在resources文件夹下创建mybatis-cfg.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="dev">
        <environment id="dev">
            <transactionManager type="JDBC"></transactionManager>
            <dataSource type="UNPOOLED">
                <property name="url" value="jdbc:mysql://localhost:3306/mybatis?serverTimezone=UTC"></property>
                <property name="driver" value="com.mysql.cj.jdbc.Driver"></property>
                <property name="username" value="root"></property>
                <property name="password" value="123456"></property>
            </dataSource>
        </environment>
    </environments>

    <mappers>
        <!--通过类路径方式引入XML文件-->
        <mapper resource="com/test/mapper/GrilMapper.xml"></mapper>
        <!--通过类的接口的权限定名引入，保持我们的接口和Mapper.xml在同包之下-->
        <!--<mapper class="com.test.mapper.GirlMapper"/>-->
        <!--<package name="com.test.mapper"/>-->
    </mappers>
</configuration>

创建mybatisUtil.class

package com.text.util;

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 MybatisUtil {

    private static SqlSessionFactory sqlSessionFactory;

    static{
        String resources = "mybatis.cfg.xml";
        InputStream in = null;
        try {
            in = Resources.getResourceAsStream(resources);
            sqlSessionFactory = new SqlSessionFactoryBuilder().build(in);
        } catch (IOException e) {
            e.printStackTrace();
        }  finally {
            if (in != null) {
                try {
                    in.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    public static SqlSession getSession(){
        return sqlSessionFactory.openSession();
    }
}

创建pojo和mapper的class文件

pojo

package com.text.pofo;

import java.util.Date;

public class Girl {
    private Long id;

    private String name;

    private String flower;

    private Date birthday;

    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 getFlower() {
        return flower;
    }

    public void setFlower(String flower) {
        this.flower = flower;
    }

    public Date getBirthday() {
        return birthday;
    }

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

GirlMapper.class

package com.test.mapper;

import com.test.pojo.Girl;

public interface GirlMapper {

    int insert(Girl girl);
}

在resources下创建mapper文件的xml版本

注意在xml文件建在class文件对应的包名下

<?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.test.mapper.GirlDao">
    <insert id="insert">
        insert into girl (name,flower,birthday)
        values (#{name},#{flower},#{birthday})
    </insert>
</mapper>