mybatis利用resultType方式实现数据库一对一查询

sqlMapConfig.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"></transactionManager>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://localhost:3306/mybatis"/>
                <property name="username" value="root"/>
                <property name="password" value="123456"/>
            </dataSource>
        </environment>
    </environments>
    <mappers>
        <mapper resource="OrdersMapperCustom.xml"/>
    </mappers>
</configuration>

OrdersMapperCustom.xml 文件：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"  
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.mx.resultMap.OrderMapperCustom">
    <!-- resultType 映射方式 -->
    <select id="findUser" resultType="com.mx.resultType.OrdresCustom">
        select orders.*,
                user.username,
                user.sex,
                user.address
        from orders,user
        where orders.user_id=user.id;
    </select>
</mapper>

Orders 类：

package com.mx.resultType;

import java.util.Date;

public class Orders {

	private int id;
	private String user_id;
	private String number;
	private Date createtime;
	private String note;
	
	public int getId() {
		return id;
	}
	public void setId(int id) {
		this.id = id;
	}
	public String getUser_id() {
		return user_id;
	}
	public void setUser_id(String user_id) {
		this.user_id = user_id;
	}
	public String getNumber() {
		return number;
	}
	public void setNumber(String number) {
		this.number = number;
	}
	public Date getCreatetime() {
		return createtime;
	}
	public void setCreatetime(Date createtime) {
		this.createtime = createtime;
	}
	public String getNote() {
		return note;
	}
	public void setNote(String note) {
		this.note = note;
	}
	@Override
	public String toString() {
		return "Orders [id=" + id + ", user_id=" + user_id + ", number=" + number + ", createtime=" + createtime
				+ ", note=" + note + "]";
	}
	
}

OrdersCustom 类：

package com.mx.resultType;

public class OrdresCustom extends Orders{

	private String username;
	private String sex;
	private String address;
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getSex() {
		return sex;
	}
	public void setSex(String sex) {
		this.sex = sex;
	}
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	
}

OrdersMapperCustom接口：

package com.mx.resultType;

import java.util.List;

public interface OrdersMapperCustom {

	public List<OrdresCustom> findUser();
}

Test 测试类：

package com.mx.resultType;

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;

public class Test {

	public static void main(String[]args) throws IOException{
		String resource = "sqlMapConfig.xml";
		InputStream is = Resources.getResourceAsStream(resource);
		SqlSessionFactory sqlSessionFactory = new SqlSessionFactoryBuilder().build(is);
		SqlSession sqlSession = sqlSessionFactory.openSession();
		
		OrdersMapperCustom omc = sqlSession.getMapper(OrdersMapperCustom.class);
		List<OrdresCustom> list=omc.findUser();
		System.out.println(list);
		sqlSession.close();
	}
}