products.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><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.14.8</version><scope>provided</scope></dependency></dependencies></project>

mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration><settings><setting name="mapUnderscoreToCamelCase" value="true"/><setting name="logImpl" value="STDOUT_LOGGING"/></settings><typeAliases><package name="com.aistart.tech.pojo"/></typeAliases><!--    <typeAliases>-->
<!--        <typeAlias alias="Products" type="com.aistart.tech.pojo.Products"/>--><!--    </typeAliases>--><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/mybatisdb"/><property name="username" value="root"/><property name="password" value="root"/><property name="poolMaximumActiveConnections" value="1"/></dataSource></environment><environment id="testdevelopment"><transactionManager type="JDBC"/><dataSource type="POOLED"><property name="driver" value="com.mysql.cj.jdbc.Driver"/><property name="url" value="jdbc:mysql://localhost:3306/test"/><property name="username" value="root"/><property name="password" value="root"/></dataSource></environment></environments><mappers><mapper resource="mapper/ProductsMapper.xml"></mapper></mappers>
</configuration>

ProductsMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="mapper.ProductsMapper"><sql id="all">product_id, product_name, brand, price, color, storage_capacity, description</sql><sql id="select">select <include refid="all"></include> from productswhere</sql><!--id作为这个sql的唯一id,调用也是通过它--><insert id="insertOne" parameterType="Products">insert into products (product_name,color,price)values (#{productName},#{color},#{price})</insert><delete id="deleteOneById">delete from products where product_id = #{askdksad}</delete><update id="updateProductName" parameterType="Products">update products set product_name = #{productName} where product_id = #{productId}</update><select id="selectOneById" parameterType="int" resultType="com.aistart.tech.pojo.Products">/*
参数名一个时虽然可以随便写,但是不推荐*/select <include refid="all"></include>from products where product_id = #{productId}/*默认调用了get函数,利用反射,根据get+param()的形式找函数并且执行*/</select><!--JDBC>>>>sql>>>>resultSet>>>获取列并遍历>>>>>>--><select id="selectAll" resultType="com.aistart.tech.pojo.Products">select <include refid="all"></include>from products</select><select id="selectOneBynName" resultType="Products"><include refid="select"></include>product_name = #{name}</select>
</mapper>

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 {@Overridepublic int insertOne(String name) {SqlSession sqlSession = DButil.getSqlSession();Products products = new Products();
//
//        products.setProductName(name);
//        products.setColor("黑色");
//        products.setPrice(19999.99);int rows = sqlSession.insert("insertOne",products );sqlSession.commit();//关闭掉sqlSession.close();return rows;}@Overridepublic Products selectOneById(int id) {SqlSession sqlSession = DButil.getSqlSession();Products one =(Products) sqlSession.selectOne("selectOneById", id);sqlSession.close();return one;}
}

Products.java

package com.aistart.tech.pojo;import lombok.*;@Data
@AllArgsConstructor
@NoArgsConstructor
public class Products {private Integer productId;private String productName;private String brand;private Double price;private String color;private String storageCapacity;private String description;}

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;//测试环境下的工厂private static SqlSessionFactory sqlSessionFactoryTest = 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);//测试环境的创建工厂
//            sqlSessionFactoryTest  = new SqlSessionFactoryBuilder().build(inputStream,"testdevelopment");} catch (IOException e) {throw new RuntimeException(e);}}public static SqlSession getSqlSession(){//获得Sqlsessionreturn sqlSessionFactory.openSession();}public static void close(SqlSession session){session.close();}}

ProductsMapperImplTest.java

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();@Testpublic void test(){Products products = mapper.selectOneById(1);System.out.println(products);}
}

MapperTest.java

import com.aistart.tech.pojo.Products;
import com.aistart.tech.utils.DButil;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;import java.util.HashMap;
import java.util.List;public class MapperTest {@Testpublic void selectAllTest(){SqlSession sqlSession = DButil.getSqlSession();/*查取多个时,调用的是selectAll,必须使用selectList函数查取单个时,调用的是selectOne,必须使用selectOne函数*/List<Products> list = sqlSession.selectOne("mapper.ProductsMapper.selectAll");//默认通过反射直接向属性放值for (Products o : list) {System.out.println(o);}}@Testpublic void deleteTest(){try(SqlSession sqlSession = DButil.getSqlSession()){HashMap<String, Object> map = new HashMap<>();map.put("productName","小米");map.put("price",1999.9);int rows = sqlSession.insert("insertOne", map);sqlSession.commit();System.out.println(rows);}catch (Exception e){}}@Testpublic void insertTest(){SqlSession sqlSession = DButil.getSqlSession();Products products = new Products();products.setProductName("getterTest");//默认调用的时get()函数,sqlSession.insert("insertOne",products);sqlSession.commit();}@Testpublic void updateTest(){SqlSession sqlSession = DButil.getSqlSession();Products products = new Products();products.setProductId(17);products.setProductName("updateTest");sqlSession.update("mapper.ProductsMapper.updateProductName",products);sqlSession.commit();}@Testpublic void selectOneBynNameTest(){SqlSession sqlSession = DButil.getSqlSession();Object o = sqlSession.selectOne("selectOneBynName", "小米");}
}