在测试用例中无法通过list对象获取第二张表的单个信息

测试用例：

@Test
public void testSelect() throws Exception{
    SqlSession sqlSession=null;
    List<Goods> list= null;
    try {
        sqlSession=MybatisUtils.openSession();
        list = sqlSession.selectList("goods.selectOneToMany");
        for(Goods goodss:list){
            System.out.println(goodss.getName()+":"+goodss.getList());
        }
    } catch (Exception e) {
        throw e;
    } finally {
        MybatisUtils.closeSession(sqlSession);
    }
}：

goods实体类(第一张表)：

package com.batis.entity;

import java.util.List;

public class Goods {
    private Integer id;
    private Integer regNo;
    private String name;
    private String sex;
    private Integer age;
    private Integer grade;
    private String major;
    private List<GoodsManger> list;

    public List<GoodsManger> getList() {
        return list;
    }

    public void setList(List<GoodsManger> list) {
        this.list = list;
    }

    public Integer getId() {
        return id;
    }

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

    public Integer getRegNo() {
        return regNo;
    }

    public void setRegNo(Integer regNo) {
        this.regNo = regNo;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public Integer getGrade() {
        return grade;
    }

    public void setGrade(Integer grade) {
        this.grade = grade;
    }

    public String getMajor() {
        return major;
    }

    public void setMajor(String major) {
        this.major = major;
    }

    @Override
    public String toString() {
        return "Goods{" +
                "id=" + id +
                ", regNo=" + regNo +
                ", name='" + name + '\'' +
                ", sex='" + sex + '\'' +
                ", age=" + age +
                ", grade=" + grade +
                ", major='" + major + '\'' +
                '}';
    }
}

goods.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="goods">
    <select id="selectAll" resultType="com.batis.entity.Goods">
        select * from student
    </select>
    <select id="selectParameter" parameterType="Integer" resultType="com.batis.entity.Goods">
        select * from student where id=#{id}
    </select>
    <select id="selectScreen" parameterType="java.util.Map" resultType="com.batis.entity.Goods">
        select * from student where age &gt; #{age} and sex =#{sex}
    </select>

    <resultMap id="goodsM" type="com.batis.entity.Goods">
        <id column="reg_no" property="regNo"></id>
        <collection property="list" select="goodsManger.selectAll" column="reg_no"/>
    </resultMap>
    <select id="selectOneToMany" resultMap="goodsM">
        select * from student limit 0,1
    </select>
</mapper>

goodsmanger实体类（第二张表）：

package com.batis.entity;

public class GoodsManger {
    private Integer regNo;
    private String phone;
    private String address;

    public Integer getRegNo() {
        return regNo;
    }

    public void setRegNo(Integer regNo) {
        this.regNo = regNo;
    }

    public String getPhone() {
        return phone;
    }

    public void setPhone(String phone) {
        this.phone = phone;
    }

    public String getAddress() {
        return address;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    @Override
    public String toString() {
        return "GoodsManger{" +
                "regNo=" + regNo +
                ", phone=" + phone +
                ", address='" + address + '\'' +
                '}';
    }
}

goodsmanger.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="goodsManger">
    <select id="selectAll" parameterType="Integer" resultType="com.batis.entity.GoodsManger">
        select * from student_manger where reg_no=#{regNo}
    </select>
</mapper>

在mybatis-config.xml中的参数与视频讲解类似，其中也添加了两张表的mapper