Mybatis快速入门

<!--Mybatis依赖-->
    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.5</version>
        </dependency>
    <!--mysql驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.34</version>
        </dependency>
    <!-- junit单元测试-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.13</version>
            <scope>test</scope>
        </dependency>
   <!--非必要 日志信息可以输出到控制台-->
        <!-- 添加slf4j日志api -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.20</version>
        </dependency>
        <!-- 添加logback-classic依赖 -->
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <version>1.2.3</version>
        </dependency>
        <!-- 添加logback-core依赖 -->
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-core</artifactId>
            <version>1.2.3</version>
        </dependency>
    </dependencies>

<properties>
        <maven.compiler.source>16</maven.compiler.source>
        <maven.compiler.target>16</maven.compiler.target>
 </properties>

<?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>
  <!--起别名，可忽略包和大小写-->
    <typeAliases>
        <package name="com.work.pojo"/>
    </typeAliases>

    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
          <!-- 数据库连接信息-->
                <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
             <property name="url" value="jdbc:mysql://localhost:3306/mybatis?useSSL=false"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
            <!--加载User类sql映射文件-->
        <mapper resource="UserMapper.xml"/>
    </mappers>
</configuration>

<?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="com.work.mapper.UserMapper">
<!--
    id:唯一标识，不能重复
    resultType:定义你sql语句操作的实体类
-->
    <select id="selectAll" resultType="user">
        select * from tb_user;
    </select>
</mapper>

 public static void main(String[] args) throws IOException {
        //1.加载Mybatis核心配置文件，获取SqlSessionFactory
        String resource = "mybatis-config.xml";
        InputStream inputStream = Resources.getResourceAsStream(resource);
   SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        //2.获取SqlSession对象
        SqlSession sqlSession = sqlSessionFactory.openSession();
        //3.执行sql
        UserMapper mapper = sqlSession.getMapper(UserMapper.class);
        List<User> users = mapper.selectAll();
        System.out.println(users);
        //4.释放资源
        sqlSession.close();
    }

public interface UserMapper {
    List<User> selectAll();
}