企业级应用开发框架(mybaits篇）--一对多关联

开发工具：IDEA（我是2021最新版本）
环境搭配：自己去搞

1.创建JAVA项目

2.导入jar包，并Add as library

3.引入配置文件

1.been下构造五个类

package main.java.bean;

public class Card {
    private Integer id;
    private String number;
    private Girl p;

    public Integer getId() {
        return id;
    }

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

    public String getNumber() {
        return number;
    }

    public void setNumber(String number) {
        this.number = number;
    }

    public Girl getP() {
        return p;
    }

    public void setP(Girl p) {
        this.p = p;
    }

    @Override
    public String toString() {
        return "Card{" +
                "id=" + id +
                ", number='" + number + ''' +
                ", p=" + p +
                '}';
    }
}

package main.java.bean;


import java.util.List;

public class Classes {

    private Integer id;
    private String name;

    private List students;

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    public List getStudents() {
        return students;
    }

    public void setStudents(List students) {
        this.students = students;
    }

    @Override
    public String toString() {
        return "Classes{" +
                "id=" + id +
                ", name='" + name + ''' +
                ", students=" + students +
                '}';
    }
}

package main.java.bean;

public class Course {
    private Integer id;
    private String name;

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    @Override
    public String toString() {
        return "Course{" +
                "id=" + id +
                ", name='" + name + ''' +
                '}';
    }
}

package main.java.bean;

public class Girl {

    private Integer id;
    private String name;
    private Integer age;

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    public Integer getAge() {
        return age;
    }

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

    @Override
    public String toString() {
        return "Person{" +
                "id=" + id +
                ", name='" + name + ''' +
                ", age=" + age +
                '}';
    }
}

package main.java.bean;


import java.util.List;

public class Schoolgirl {
    private Integer id;
    private String name;
    private Integer age;

    private List courses;

    public Integer getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

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

    public Integer getAge() {
        return age;
    }

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

    public List getCourses() {
        return courses;
    }

    @Override
    public String toString() {
        return "Student{" +
                "id=" + id +
                ", name='" + name + ''' +
                ", age=" + age +
                ", courses=" + courses +
                '}';
    }

    public void setCourses(List courses) {
        this.courses = courses;
    }
}

2.编写接口和一对多关联以及测试类

package main.java.one_to_many;

import main.java.bean.Classes;
import org.apache.ibatis.annotations.Many;
import org.apache.ibatis.annotations.Result;
import org.apache.ibatis.annotations.Results;
import org.apache.ibatis.annotations.Select;

import java.util.List;

public interface ClassesMapper {


    @Select("select * from classes")
    @Results({
            @Result(column = "id" ,property = "id"),
            @Result(column = "name",property = "name"),
            @Result(
                    column = "id",
                    javaType = List.class,//根据被包含对象的实际类型
                    property = "students",//被包含对象的变量名

                    //many  @Many 一对多
                    many=@Many(select="chinasoft.one_to_many.StudentMapper.selectByCid")
            )

    })
    public List selectAll();
}

package main.java.one_to_many;

import main.java.bean.Girl;
import org.apache.ibatis.annotations.Select;

import java.util.List;

//com.chinasoft.one_to_many.StudentMapper.selectByCid
public interface StudentMapper {
    @Select("select * from student where cid=#{cid}")
    public List selectByCid(Integer cid);
}

package main.java.one_to_many;

import main.java.bean.Classes;
import main.java.bean.Schoolgirl;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import org.junit.Test;

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

public class Test01 {
    @Test
    public void selectAll() throws IOException {
        InputStream is = Resources.getResourceAsStream("MyBatisConfig.xml");
        SqlSession sqlSession = new SqlSessionFactoryBuilder().build(is).openSession(true);
        ClassesMapper mapper = sqlSession.getMapper(ClassesMapper.class);

        List list = mapper.selectAll();
        for (Classes cls:
             list) {
            System.out.println(cls.getId()+","+cls.getName());
            List ss = cls.getStudents();
            for(Schoolgirl s:ss){
                System.out.println("t"+s);
            }
        }

        sqlSession.close();
        is.close();
    }
}

最后报错了，没有找到相关配置文件。
晕(((φ(◎ロ◎;)φ)))。。。。。。