mybatis学习笔记（1）基本环境

╰+哭是因爲堅強的太久メ 2023-08-17 16:05 78阅读 0赞

#     1.pom引入 #

<dependencies>
            <dependency>
                <groupId>org.mybatis</groupId>
                <artifactId>mybatis</artifactId>
                <version>3.4.1</version>
            </dependency>
            <dependency>
                <groupId>com.google.code.gson</groupId>
                <artifactId>gson</artifactId>
                <version>2.8.5</version>
            </dependency>
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>8.0.17</version>
            </dependency>
        </dependencies>

# 　　2. config配置。在resource下添加 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.jdbc.Driver"/>
                    <property name="url" value=""/>
                    <property name="username" value=""/>
                    <property name="password" value=""/>
                </dataSource>
            </environment>
        </environments>
        <mappers>
            
            <mapper resource="learn/mybatis/CarrierMapper.xml"/>
        </mappers>
    </configuration>

# 　　3.添加开发需要的mapper，实体类 #

CarrierMapper.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="learn.mybatis.CarrierMapper">
        <select id="queryAll" resultType="learn.mybatis.Carrier">
            select id, carrier_no carrierNo, carrier_name carrierName, main_page mainPage from t_carrier  where is_deleted = 0
        </select>
    </mapper>

CarrierMapper.java

package learn.mybatis;
    
    import java.util.List;
    
    /**
     * Create by tianqing on 2019/7/24.
     */
    public interface CarrierMapper {
        List<Carrier>  queryAll();
    }

Carrier.java

public class Carrier {
        private Long id;
    
        private String carrierNo;
    
        private String carrierName;
    
        private String mainPage;
    
        /**
         * 承运商类型
         */
        private Integer carrierType;
    
        private Integer isDeleted;
    
        private String creator;
    
        private String editor;
    
        private Date createTime;
    
        private Date editTime;
    
        getset...
    }

# 　　4.整体目录结构 #

![1143792-20190724105734511-2070560516.png][]

# 5.运行main方法。 #

package learn.mybatis;
    
    import com.google.gson.Gson;
    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 org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    
    import java.io.InputStream;
    import java.util.List;
    
    /**
     * Create by tianqing on 2019/7/23.
     */
    public class MybatisLearn {
        private static final Logger logger = LoggerFactory.getLogger(MybatisLearn.class);
    
        public static void main(String[] args) throws Exception {
            //前三步都相同
            InputStream inputStream = Resources.getResourceAsStream("mybatis-config.xml");
            SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(inputStream);
            SqlSession sqlSession = factory.openSession();
            //这里不再调用SqlSession 的api，而是获得了接口对象，调用接口中的方法。
            CarrierMapper mapper = sqlSession.getMapper(CarrierMapper.class);
            List<Carrier> carriers = mapper.queryAll();
            Gson gson = new Gson();
            logger.info("[MybatisLearn - main] 结果：{}", gson.toJson(carriers));
    
        }
    }

# 　　6.执行并打印。 #

![1143792-20190724105843742-873933966.png][]

跑起来以后。我们不着急多种用法，下一章大致研究下 mybatis怎么实现的

转载于:https://www.cnblogs.com/zhimingxin/p/11236675.html

[1143792-20190724105734511-2070560516.png]: /images/20230810/aac0a0b069974714a0337106ebeb0084.png
[1143792-20190724105843742-873933966.png]: /images/20230810/bfec9119985245a6b6bc06f3a3c2de30.png