Mybatis中通过建立实体类关系进行一对一查询

Account类：

package com.qublog.domain;

import java.io.Serializable;

public class Account implements Serializable {
    private Integer id;
    private Integer uid;
    private Double money;

    //从表实体应该包含一个主表实体的对象引用
    private User user;

    public User getUser() {
        return user;
    }

    public void setUser(User user) {
        this.user = user;
    }

    public Integer getId() {
        return id;
    }

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

    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;
    }

    @Override
    public String toString() {
        return "Account{" +
                "id=" + id +
                ", uid=" + uid +
                ", money=" + money +
                '}';
    }
}

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">
<mapper namespace="com.qublog.dao.AccountDao">
    <!-- 定义封装account和user的resultMap -->
    <resultMap id="accountUserMap" type="account">
        <id property="id" column="aid"></id>
        <result property="uid" column="uid"></result>
        <result property="money" column="money"></result>
        <!-- 一对一的关系映射，配置封装user的内容 -->
        <association property="user" column="uid" javaType="user">
            <id property="id" column="id"></id>
            <result property="username" column="username"></result>
            <result property="address" column="address"></result>
            <result property="sex" column="sex"></result>
            <result property="birthday" column="birthday"></result>
        </association>

    </resultMap>

    <!-- 配置查询所有 -->
    <select id="findAll" resultMap="accountUserMap">
        select u.*, a.id as aid, a.uid, a.money from account a, user u where a.uid=u.id;
    </select>

    <!-- 配置查询所有同时包含用户名和地址信息 -->
    <select id="findAllAccount" resultType="accountuser">
        select a.*, u.username, u.address from account a, user u where a.uid=u.id;
    </select>
</mapper>

AccountTest类中修改如下：

    @Test
    public void testFindAll() throws Exception {
        //执行查询所有方法
        List<Account> accounts = accountDao.findAll();
        for (Account account:accounts) {
            System.out.println("-----------每个account的信息-------------");
            System.out.println(account);
            System.out.println(account.getUser());
        }
    }