Mybaties模式的嵌入

Mybaties模式的嵌入

<?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="aaa">
    <!--public List<Dept> findAll(){    }-->
    <select id="findAll" resultType="com.msb.pojo.Dept" >
        select * from dept
    </select>
</mapper>

<?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.cj.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://127.0.0.1:3306/mydb?useSSL=false&amp;useUnicode=true&amp;characterEncoding=UTF-8&amp;serverTimezone=Asia/Shanghai"/>
                <property name="username" value="root"/>
                <property name="password" value="root"/>
            </dataSource>
        </environment>
    </environments>
    <!--加载mapper映射文件-->
    <mappers>
        <mapper resource="com/msb/mapper/DeptMapper.xml"/>
    </mappers>
</configuration>

实体类Dept

package com.msb.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.io.Serializable;
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Dept implements Serializable {
    private Integer deptno;
    private String dname;
    private String loc;
}

pop文件加载相关依赖

<?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.msb</groupId>
    <artifactId>MybtiesDemo01</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>
    <properties>
        <maven.compiler.source>8</maven.compiler.source>
        <maven.compiler.target>8</maven.compiler.target>
    </properties>
    <dependencies>
        <!--mysqlConnector-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.16</version>
        </dependency>
        <!--mybatis 核心jar包-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.3</version>
        </dependency>
        <!--junit-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13.1</version>
            <scope>test</scope>
        </dependency>
        <!--lombok -->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>
</project>

固定必须先执行的和最后执行的方法设计

import com.msb.pojo.Dept;
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.junit.After;
import org.junit.Before;
import org.junit.Test;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
public class Test1 {
    SqlSession sqlSession = null;
   @Before
   public void test1(){
       //首先做一个对象SqlSessionFactoryBuilder建立一个绘话
       SqlSessionFactoryBuilder ssfb = new SqlSessionFactoryBuilder();
       //有一个文本输入的io流进行读取操作
       InputStream stream = null;
       try {
           //这里的路径直接会定位到配置文件classes下面；所以这个文件在次目录下--编译和
           //-图纸；对数据库文件进行读取，获取一个io流，由于配置文件在classes下面，直接写文件名即可
           stream = Resources.getResourceAsStream("sqlMapConfig.xml");
       } catch (IOException e) {
           e.printStackTrace();
       }
       //build需要指向一个文件进行读取出来--工厂
       SqlSessionFactory factory = ssfb.build(stream);
        //需要用sqlSession去调用增删改查--工人去获取数据，打开这个绘话
       sqlSession = factory.openSession();
   }
    @Test
    public void tese2(){
        List<Dept> list = sqlSession.selectList("findAll");
        for (Dept dept : list) {
            System.out.println(dept);
        }
    }
    @After
    public void test3(){
       if (sqlSession!=null){
           sqlSession.close();
       }
    }
}