Mybatis配置

1.导入相关jar包

2.在src下创建配置文件mybatis-config.xml

    把数据源信息编写完整----通过mybatis完成对数据库中数据源的增删查改

3.创建class类com.hd.pojo中的javabean

4.mybatis是半自动化的ORM,所有的sql语句都写在UserMapper.xml映射文件中

5.映射文件建好后,配置到mybatis-config.xml文件中

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">
	<configuration>
	<environments default="development">
	<environment id="development">
	<transactionManager type="JDBC"/>
	<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="car"/>
	<property name="password" value="car"/>
	</dataSource>
	</environment> 
	</environments>
	<mappers>
	<mapper resource="com/hd/pojo/UserMapper.xml"/>
	</mappers>
	</configuration>

UserBean文件

package com.hd.pojo;

public class UserBean {
	
	private int id;
	
	private String username;
	
	private String pwd;
	
	private String realname;

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getUsername() {
		return username;
	}

	public void setUsername(String username) {
		this.username = username;
	}

	public String getPwd() {
		return pwd;
	}

	public void setPwd(String pwd) {
		this.pwd = pwd;
	}

	public String getRealname() {
		return realname;
	}

	public void setRealname(String realname) {
		this.realname = realname;
	}

	@Override
	public String toString() {
		return "UserBean [id=" + id + ", username=" + username + ", pwd=" + pwd
				+ ", realname=" + realname + "]";
	}
	
	
}

UserMapper.xml文件

<?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.hd.pojo.UserMapper">
		<!-- 查询所有用户的信息
			id:自定义 唯一 见名知意
			resultType:接收数据的类型
		 -->
		
		<select id="queryAll" resultType="com.hd.pojo.UserBean">
		select * from t_user
		</select>
			
	</mapper>

UserTest文件

package com.hd.test;

import java.io.IOException;
import java.io.InputStream;
import java.util.List;

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.Test;

import com.hd.pojo.UserBean;

public class UserTest {
	@Test
	public void test() throws IOException{
		//1.加载配置文件
		InputStream in = Resources.getResourceAsStream("mybatis-config.xml");
		//2.获取对应的SQLSessionFactory对象
		SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(in);
		//3.获取对应的session对象
		SqlSession session = factory.openSession();
		//com.hd.pojo.UserMapper.queryAll拼接的映射文件及其中的方法
		List<UserBean> list = session.selectList("com.hd.pojo.UserMapper.queryAll");
		for(UserBean user : list){
			System.out.println(user);
		}
		//5.关闭session
		session.close();
		
	}
	
}