Mybatis的使用

Posted 2020-11-07 消失的那两年

Mybatis使用流程：

 第一步:先引入要使用的jar包：

             mybatis-3.3.0.jar
             ojdbc6.jar

第二步：建立Mybatis-config.xml文件

        

<?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">
<!-- 配置 ,如果和sping结合以后，这个配置就不用了 -->
<configuration>
	<!-- 定义很多环境，默认环境是development -->

	<environments default="development">
		<environment id="development">
		    <!-- 事物管理採用JDBC的事務 -->
			<transactionManager type="JDBC" />
			<!-- 連接池採用的POOLED連接池 -->
			<dataSource type="POOLED">
				<property name="driver" value="oracle.jdbc.driver.OracleDriver" />
				<property name="url" value="jdbc:oracle:thin:@localhost:1521:orcl" />
				<property name="username" value="scott" />
				<property name="password" value="tiger" />

			</dataSource>
		</environment>
	</environments>


     <!-- 配置Mybatis的映射文件 -->
	<mappers>
		<mapper resource="com/ysd/dao/IUserMapper.xml"></mapper>
	</mappers>


</configuration>

　　第二步：建立 IUserDao接口

package com.ysd.dao;

public interface IUserDao {
	public int vgetCount();
}

　　第三步：建立 IUserDaoMapper.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http//mybaatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.ysd.dao.IUserDao">
      <select id="vgetCount" resultType="int">
             select count(*) from emp
      </select>
</mapper>

　　第四步：建立测试文件

package test;

import java.io.IOException;
import java.io.InputStream;

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 com.ysd.dao.IUserDao;

public class testMybatis {
	public static void main(String[] args) {
		String configString = "mybatis-config.xml";
		// 输入流
		InputStream inputStream = null;
		// sql会工厂
		SqlSessionFactory sessionFactory = null;
		// sql会话
		SqlSession sqlSession = null;

		try {
			SqlSessionFactoryBuilder builder = new SqlSessionFactoryBuilder();
			inputStream = Resources.getResourceAsStream(configString);
			// 得到会话工厂
			sessionFactory = builder.build(inputStream);
			// 得到sql会话
			sqlSession = sessionFactory.openSession();
			IUserDao iuserdao = sqlSession.getMapper(IUserDao.class);
			int num = iuserdao.vgetCount();
			System.out.println("袁表里面总共有" + num + "条数据，。");
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

	}
}