代码部分

com.qingruan.bean目录下创建Account.java和AccountUser.java

1、Account.java

package com.qingruan.bean;

public class Account {
    private Integer aid;
    private Integer uid;
    private double money;

    public Integer getAid() {
        return aid;
    }

    public void setAid(Integer aid) {
        this.aid = aid;
    }

    public Integer getUid() {
        return uid;
    }

    public void setUid(Integer uid) {
        this.uid = uid;
    }

    public double getMoney() {
        return money;
    }

    public void setMoney(double money) {
        this.money = money;
    }
}

2、AccountUser.java

package com.qingruan.bean;

public class AccountUser extends Account{
    //同时包含用户信息以及账户信息
    private String username;
    private String sex;

    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;
    }

    @Override
    public String toString() {
        return "aid:"+this.getAid()+",money:"+this.getMoney()+",username:"
                +this.getUsername()+",sex:"+this.getSex();
    }
}

IAccountDao.java

package com.qingruan.dao;

import com.qingruan.bean.AccountUser;

import java.util.List;

public interface IAccountDao {
    /**
     * 查询所有用户，同时获得账户的所属用户信息以及用户名称和性别
     */
    List<AccountUser> findAll();
}

4、AccountDao.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">

<!--namespace 命名空间    包的全限定名   包名+类名 -->
<mapper namespace="com.qingruan.dao.IAccountDao">

    <select id="findAll" resultType="accountUser">
        SELECT a.*,u.`username`,u.`sex` FROM t_account a,t_user u WHERE a.`uid`=u.`id`
    </select>

</mapper>

5、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>
<!--    指定日志引用的是log4j-->
    <settings>
        <setting name="logImpl" value="LOG4J"/>
    </settings>

    <!--给实体类配置别名-->
    <typeAliases>

        <!--批量定义别名，扫描整个包下的所有的类，别名为类名，首字母大小写都可以-->
        <package name="com.qingruan.bean"/>
    </typeAliases>

    <!--可以设置多个运行环境，满足不同需要，例如 开发、测试、生产环境上有不同一配置 -->
    <environments default="mysql">
        <environment id="mysql">
            <!--事务管理类型主要有jdbc和managed,前者依赖于数据源获得的连接，后者依赖于容器 -->
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <!-- 如果数据库设置为UTF-8,则URL参数连接需要添加?useUnicode=true&amp;characterEncoding=UTF-8，如下 -->
                <property name="url" value="jdbc:mysql://localhost:3306/mydata1?useUnicode=true&amp;characterEncoding=UTF-8"/>
                <property name="username" value="root"/>
                <property name="password" value="1234"/>
            </dataSource>
        </environment>
    </environments>

<!--    告知mybaties映射配置的位置-->
    <mappers>
        <mapper resource="com/qingruan/dao/AccountDao.xml"></mapper>

    </mappers>

</configuration>

6、MyBatisTest.java

package com.qingruan.test;

import com.qingruan.bean.AccountUser;
import com.qingruan.dao.IAccountDao;
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.After;
import org.junit.Before;
import org.junit.Test;

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

public class MyBatisTest {
    private InputStream is;
    private SqlSessionFactoryBuilder builder;
    private SqlSessionFactory sessionFactory;
    private SqlSession session;
    private IAccountDao dao;

    @Before //在测试方法执行之前执行
    public void init() throws  Exception{
        is=Resources.getResourceAsStream("mybatis-config.xml");
        //创建sqlSessionFacotory的构建着对象
        builder=new SqlSessionFactoryBuilder();
        //通过构建着对象创建工厂对象
        sessionFactory = builder.build(is);
        //获得session对象
        session = sessionFactory.openSession();
        //使用session创建dao接口的代理对象
        dao = session.getMapper(IAccountDao.class);
    }

    @After  //在测试方法执行完成之后执行
    public void destroy() throws  Exception{
        //提交事务  增删改后一定要控制事物的提交
        session.commit();
        //方式资源
        session.close();
        is.close();
    }


    /**
     * 查账户的同时，显示用户信息，包括姓名和性别
     */
    @Test
    public void testFindAll(){
       List<AccountUser> list = dao.findAll();
       for (AccountUser accountUser : list) {
           System.out.println(accountUser);
       }

   }

}

【mybatis一对一查询】方法一：resultType

代码部分

运行结果

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