OrderItem.java

package com.programmers.springbootjpa.entity;

import jakarta.persistence.*;
import lombok.Getter;
import lombok.Setter;

import java.util.Objects;

@Entity
@Table(name = "order_item")
@Getter
@Setter
public class OrderItem extends BaseTimeEntity {

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE)
    private Long id;

    @Column(nullable = false)
    private Integer quantity;

    @Column(nullable = false)
    private Integer price;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "order_id", referencedColumnName = "id")
    private Order order;

    public void updateOrder(Order order) {
        if (Objects.nonNull(this.order)) {
            this.order.removeOrderItem(this);
        }

        this.order = order;
        order.addOrderItem(this);
    }
}