数据库ORM框架mybatis 学习篇

1,老套路加载依赖库或者jar

<dependency>
  <groupId>org.mybatis</groupId>
  <artifactId>mybatis</artifactId>
  <version>3.4.7</version>
</dependency>```
 <!-- mysql驱动 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.18</version>
        </dependency>


2.配置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>
   <typeAliases>
     <typeAlias alias="Demo" type="bean.Demo"/>
    </typeAliases>
  <environments default="development">
    <environment id="development">
      <transactionManager type="JDBC"/>
      <dataSource type="POOLED">
        <property name="driver" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql:///stu"/>
        <property name="username" value="root"/>
        <property name="password" value="123456"/>
      </dataSource>
    </environment>
  </environments>
  <mappers>
    <mapper resource="DemoMapper.xml"/>
  </mappers>
</configuration>

3 配置"DemoMapper.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="bean.Demo.UserMapper">
	<select id="selectUserByID" parameterType="int" resultType="Demo">
		select * from demo where id = #{id}
    </select>
</mapper>


4测试 注明(持久化对象,创建数据库略过)这里认为你是 熟悉Java的童鞋


@Test*斜体样式*
public void testMybatis() {
	String resource = "mybatis-config.xml";**//注意配置classpath 下**
	InputStream inputStream;
	try {
		inputStream = Resources.getResourceAsStream(resource);
		SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
	   SqlSession s= sqlSessionFactory.openSession();
	  Demo d= (Demo)s.selectOne("bean.Demo.UserMapper.selectUserByID", 3);
	  System.out.println("----"+d.getId());
	  System.out.println("----"+d.getName());

	} catch (IOException e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
	}

}
10-06 18:12