mybatis 模拟03

news2025/1/11 16:44:22

pom.xml:

<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.wsd</groupId>
    <artifactId>mybatis</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <!--dom4j依赖-->
        <dependency>
            <groupId>org.dom4j</groupId>
            <artifactId>dom4j</artifactId>
            <version>2.1.3</version>
        </dependency>
        <!--jaxen依赖-->
        <dependency>
            <groupId>jaxen</groupId>
            <artifactId>jaxen</artifactId>
            <version>1.2.0</version>
        </dependency>
        <!--mysql驱动依赖-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.30</version>
        </dependency>
        <!--junit依赖-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13.2</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
                <configuration>
                    <source>17</source>
                    <target>17</target>
                </configuration>
            </plugin>
        </plugins>
    </build>


</project>

配置文件

mybatis-config.xml:

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

mapper文件

CarMapper.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="car">
    <!--insert sql：保存一个汽车信息-->
    <insert id="insertCar">
        insert into t_car
            (id,car_num,brand,guide_price,produce_time,car_type)
        values
            (null,#{carNum},#{brand},#{guidePrice},#{produceTime},#{carType})
    </insert>

    <delete id="deleteByCarNum">
        delete from t_car where car_num = #{carNum}
    </delete>

    <update id="updateCarById">
        update t_car set
            car_num = #{carNum},
            brand = #{brand},
            guide_price = #{guidePrice},
            produce_time = #{produceTime},
            car_type = #{carType}
        where id = #{id}
    </update>

    <select id="selectCarById" resultType="com.wsd.pojo.Car">
        select id,car_num as carNum,brand,guide_price as guidePrice,produce_time as produceTime,car_type as carType
        from t_car
        where id = #{id}
    </select>

    <!--虽然结果是List集合，但是resultType属性需要指定的是List集合中元素的类型。-->
    <select id="selectCarAll" resultType="com.wsd.pojo.Car">
        <!--记得使用as起别名，让查询结果的字段名和java类的属性名对应上。-->
        select
        id, car_num as carNum, brand, guide_price as guidePrice, produce_time as produceTime, car_type as carType
        from
        t_car
    </select>
</mapper>

test:

package com.wsd.core;

import com.wsd.core.util.Resources;
import org.dom4j.DocumentException;
import org.junit.Test;

/**
 * @description: test
 * @author: Mr.Wang
 * @create: 2023-06-24 15:40
 **/
public class TestMyBatis {

    @Test
    public void testSqlSessionFactory(){
        SqlSessionFactoryBuilder sqlSessionFactoryBuilder = new SqlSessionFactoryBuilder();
        try {
            SqlSessionFactory sqlSessionFactory = sqlSessionFactoryBuilder.build(Resources.getResourcesAsStream("mybatis-config.xml"));
            System.out.println(sqlSessionFactory);
        } catch (DocumentException e) {
            e.printStackTrace();
        }

    }
}