02 mybatis

文章目录

• • product.sql
  • pom.xml
  • mybatis-config.xml
  • mapper.ProductsMapper.xml
  • pojo.products.java
  • utils.DButil.java
  • mapper.impl.ProductsMapperImpl.java
  • test

product.sql

create table products
(
    product_id       int auto_increment comment '产品ID'
        primary key,
    product_name     varchar(100)   null comment '产品名称',
    brand            varchar(50)    null comment '品牌',
    price            decimal(10, 2) null comment '价格',
    color            varchar(20)    null comment '颜色',
    storage_capacity varchar(10)    null comment '存储容量',
    description      text           null comment '描述'
)
    comment '手机产品表';

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.aistat</groupId>
    <artifactId>mybatis_tech</artifactId>
    <version>1.0-SNAPSHOT</version>

    <!--打包类型-->
    <packaging>jar</packaging>

    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <!--所有依赖-->
    <dependencies>

<!--        MySQL驱动-->
        <dependency>
            <groupId>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
            <version>8.0.31</version>
        </dependency>

<!--        mybatis依赖-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.15</version>
        </dependency>

        <!--测试环境-->

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13.2</version>
            <scope>test</scope>
        </dependency>

    </dependencies>

</project>

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>
    
    <settings>
        <setting name="mapUnderscoreToCamelCase" value="true"/>
    </settings>
    
    <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://localhost:3306/dict"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <mapper resource="mapper/ProductsMapper.xml"></mapper>
    </mappers>
</configuration>

mapper.ProductsMapper.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="mapper.ProductsMapper">

    <!--id作为这个sql的唯一id,调用也是通过它-->
    <insert id="insertOne" parameterType="com.aistart.tech.pojo.Products">
        insert into products (product_name,color,price)
        values (#{productName},#{color},#{price})
    </insert>

    <select id="selectOneById" parameterType="int" resultType="com.aistart.tech.pojo.Products">

        select * from products where product_id = #{id}

    </select>
</mapper>

pojo.products.java

package com.aistart.tech.pojo;


public class Products {

  private Integer productId;
  private String productName;
  private String brand;
  private double price;
  private String color;
  private String storageCapacity;
  private String description;


  public Integer getProductId() {
    return productId;
  }

  public void setProductId(Integer productId) {
    this.productId = productId;
  }


  public String getProductName() {
    return productName;
  }

  public void setProductName(String productName) {
    this.productName = productName;
  }


  public String getBrand() {
    return brand;
  }

  public void setBrand(String brand) {
    this.brand = brand;
  }


  public double getPrice() {
    return price;
  }

  public void setPrice(double price) {
    this.price = price;
  }


  public String getColor() {
    return color;
  }

  public void setColor(String color) {
    this.color = color;
  }


  public String getStorageCapacity() {
    return storageCapacity;
  }

  public void setStorageCapacity(String storageCapacity) {
    this.storageCapacity = storageCapacity;
  }


  public String getDescription() {
    return description;
  }

  public void setDescription(String description) {
    this.description = description;
  }


}

utils.DButil.java

package com.aistart.tech.utils;

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 DButil {

    private static SqlSessionFactory sqlSessionFactory = null;

    static {
        //1.builder  一旦创建了 SqlSessionFactory，就不再需要它了
//        SqlSessionFactoryBuilder sqlSessionFactoryBuilder =

        //2.获取工厂

        // 获取资源 org.apache.ibatis.io.Resources;
        try {

            InputStream inputStream = Resources.getResourceAsStream("mybatis-config.xml");
            //根据资源文件创建工厂
            sqlSessionFactory  = new SqlSessionFactoryBuilder().build(inputStream);



        } catch (IOException e) {
            throw new RuntimeException(e);
        }


    }

    public static SqlSession getSqlSession(){

        //获得Sqlsession
        return sqlSessionFactory.openSession();

    }

    public static void close(SqlSession session){

        session.close();

    }


}

mapper.impl.ProductsMapperImpl.java

package com.aistart.tech.mapper.impl;

import com.aistart.tech.mapper.ProductsMapper;
import com.aistart.tech.pojo.Products;
import com.aistart.tech.utils.DButil;
import org.apache.ibatis.session.SqlSession;


public class ProductsMapperImpl implements ProductsMapper {
    @Override
    public int insertOne(Products products) {

        SqlSession sqlSession = DButil.getSqlSession();

        System.out.println(products.getProductName());

        int rows = sqlSession.insert("insertOne",products );

        sqlSession.commit();

        //关闭掉
        sqlSession.close();

        return rows;
    }

    @Override
    public Products selectOneById(int id) {

        SqlSession sqlSession = DButil.getSqlSession();

        Products one =(Products) sqlSession.selectOne("selectOneById", id);

        sqlSession.close();

        return one;
    }
}

test

package com.aistart.tech.mapper.impl;

import com.aistart.tech.mapper.ProductsMapper;
import com.aistart.tech.pojo.Products;
import org.junit.Test;

public class ProductsMapperImplTest {

    ProductsMapper mapper = new ProductsMapperImpl();

    @Test
    public void test(){
        Products products = mapper.selectOneById(1);

        System.out.println(products);


       products.setProductName("小米");
       products.setColor("红色");
       products.setPrice(200);

        System.out.println(products.getProductName());
        int rows = mapper.insertOne(products);
        System.out.println(rows);


    }
}