인프런 커뮤니티 질문&답변

package jpabook.jpashop.service;

import jpabook.jpashop.domain.Address;
import jpabook.jpashop.domain.Member;
import jpabook.jpashop.domain.Order;
import jpabook.jpashop.domain.OrderStatus;
import jpabook.jpashop.domain.item.Item;
import jpabook.jpashop.exception.NotEnoughStockException;
import jpabook.jpashop.repository.OrderRepository;
import org.junit.Assert;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.context.annotation.EnableMBeanExport;
import org.springframework.test.context.junit4.SpringRunner;
import org.springframework.transaction.annotation.Transactional;

import javax.persistence.EntityManager;
import java.awt.print.Book;

import static org.junit.Assert.*;

@RunWith(SpringRunner.class)
@SpringBootTest
@Transactional
public class OrderServiceTest {

    @Autowired EntityManager em;
    @Autowired OrderService orderService;
    @Autowired
    OrderRepository orderRepository;
    /**
     * 상품 주문
     */
    @Test
    public void order() {

        // given
        Member member = createMember();

        Book book = createBook("시골 JPA", 10000, 10);

        int orderCount = 2;

        // when
        Long orderId = orderService.order(member.getId(), book.getId(), orderCount);

        // then
        Order getOrder = orderRepository.findOne(orderId);

        assertEquals("상품 주문시 상태는 ORDER", OrderStatus.ORDER, getOrder.getStatus());
        assertEquals("주문한 상품 종류 수가 정확해야 한다.", 1, getOrder.getOrderItems().size());
        assertEquals("주문 가격은 가격 * 수량이다.", 1000 * orderCount, getOrder.getTotalPrice());
        assertEquals("주문 수량만큼 재고가 줄어야 한다.", 8, book.getStockQuantity());
    }

    /**
     * 주문취소
     */
    @Test
    public void cancelOrder() {

        Member member = createMember();
        Book item = createBook("시골 JPA", 10000, 10);

        int orderCount = 2;
        Long orderId = orderService.order(member.getId(), item.getId(), orderCount);

        orderService.cancelOrder(orderId);

        Order getOrder = orderRepository.findOne(orderId);

        assertEquals("주문 취소시 상태는 CANCEL 이다.", OrderStatus.CANCEL, getOrder.getStatus());
        assertEquals("주문이 취소된 상품은 그만큼 재고가 증가해야한다.", 10, item.getStockQuantity());
    }

    /**
     * 재고수량 초과
     */
    @Test(expected = NotEnoughStockException.class)
    public void 상품주문_재고수량초과() throws Exception{


        // given
        Member member = createMember();
        Item item = createBook("시골 JPA", 10000, 10);

        int orderCount = 11;

        // when
        orderService.order(member.getId(), item.getId(), orderCount);

        // then
        fail("재고 수량 부족 예외가 발생해야 한다.");

    }

    private Book createBook(String name, int price, int stockQuantity) {
        Book book = new Book();
        book.setName(name);
        book.setPrice(price);
        book.setStockQuantity(stockQuantity);
        em.persist(book);
        return book;
    }

    private Member createMember() {
        Member member = new Member();
        member.setName("회원1");
        member.setAddress(new Address("서울", "강가", "123-123"));
        em.persist(member);
        return member;
    }

package jpabook.jpashop.domain.item;

import jpabook.jpashop.domain.Category;
import jpabook.jpashop.exception.NotEnoughStockException;
import lombok.Getter;
import lombok.Setter;

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

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

    @Id
    @GeneratedValue
    @Column(name = "item_id")
    private Long id;

    private String name;
    private int price;
    private int stockQuantity;

    @ManyToMany(mappedBy = "items")
    private List<Category> categories = new ArrayList<>();

    // == 비즈니스 로직 == //
    // stockQuantity의 경우, Item 엔티티 내에만 있으므로 해당 클래스에서 비즈니스 로직을 설정(엔티티 주도 설계)

    /**
     * 재고 수량 증가*
     * */
    public void addStock(int quantity){
        this.stockQuantity += quantity;
    }

    /**
     * 재고 수량 감소*
     * */
    public void removeStock(int quantity){
        int restStock = this.stockQuantity - quantity;
        if(restStock<0){
            throw new NotEnoughStockException("need more stock");
        }
        this.stockQuantity = restStock;
    }

}

package jpabook.jpashop.domain.item;

import lombok.Getter;
import lombok.Setter;

import javax.persistence.DiscriminatorValue;
import javax.persistence.Entity;

@Entity
@DiscriminatorValue("B")
@Getter @Setter
public class Book extends Item{

    private String author;
    private String isbn;
}