인프런 커뮤니티 질문&답변

@ManyToMany를 다대일 일대다 관계로 바꿔보았는데 

이렇게 바꾸는 게 맞을까요??

<CategoryItem.java>

package jpabook.jpashop.domain;

import jpabook.jpashop.domain.item.Item;
import lombok.Getter;
import lombok.Setter;

import javax.persistence.*;

@Entity
@Getter @Setter
public class CategoryItem {

    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "category_item_id")
    private Long id;

    @ManyToOne
    @JoinColumn(name = "category_id")
    private Category category;

    @ManyToOne
    @JoinColumn(name = "item_id")
    private Item item;
}

<Category.java>

package jpabook.jpashop.domain;

import jpabook.jpashop.domain.item.Item;
import lombok.Getter;
import lombok.Setter;

import javax.persistence.*;
import java.util.ArrayList;
import java.util.List;

import static javax.persistence.FetchType.*;

@Entity
@Getter @Setter
public class Category {

    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "category_id")
    private Long id;

    private String name;

    @ManyToOne(fetch = LAZY)
    @JoinColumn(name = "parent_id")
    private Category parent;

    @OneToMany(mappedBy = "parent")
    private List<Category> child = new ArrayList<>();
}

<Item.java>

package jpabook.jpashop.domain.item;

import jpabook.jpashop.domain.Category;
import jpabook.jpashop.domain.CategoryItem;
import lombok.Getter;
import lombok.Setter;

import javax.persistence.*;
import java.util.ArrayList;
import java.util.List;

@Entity
@Getter @Setter
@Inheritance(strategy = InheritanceType.SINGLE_TABLE)
@DiscriminatorColumn(name = "DTYPE")
public abstract class Item {

    @Id @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "item_id")
    private Long id;
    private String name;
    private int price; // 가격
    private int stockQuantity; // 재고수량

    @OneToMany(mappedBy = "item")
    private List<CategoryItem> categoryItems = new ArrayList<>();
}