Spring boot Hibernate 一對多關系

Question

我有兩個實體產品和產品選項。 產品可以有多個產品選項，可以看出我已經將它與 oneToMany 關系進行了映射。

@Entity
public class Product {

    @Id
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    private int id;
    private String description;
    private String productCategory;
    private String optionDescription;
    private BigDecimal productBasePrice;
    @OneToMany(mappedBy = "product",cascade = CascadeType.ALL)
    private Set<ProductOption>productOptions=new HashSet<>();


    public Product() {}
    public Product(String description, ProductCategory productCategory,String optionDescription, BigDecimal productBasePrice) {
        super();
        this.description = description;
        this.productCategory=productCategory.toString();
        this.optionDescription = optionDescription;
        this.productBasePrice = productBasePrice;
    }


    public int getId() {
        return id;
    }


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


    public String getDescription() {
        return description;
    }


    public String getProductCategory() {
        return productCategory;
    }
    public void setProductCategory(String productCategory) {
        this.productCategory = productCategory;
    }
    public void setDescription(String description) {
        this.description = description;
    }


    public String getOptionDescription() {
        return optionDescription;
    }


    public void setOptionDescription(String optionDescription) {
        this.optionDescription = optionDescription;
    }


    public BigDecimal getProductBasePrice() {
        return productBasePrice;
    }


    public void setProductBasePrice(BigDecimal productBasePrice) {
        this.productBasePrice = productBasePrice;
    }


    public Set<ProductOption> getProductOptions() {
        return productOptions;
    }


    public void setProductOptions(Set<ProductOption> productOptions) {
        this.productOptions = productOptions;
    }


}

和產品選項

@Entity
public class ProductOption {
    @Id
    @GeneratedValue(strategy=GenerationType.AUTO)
    private Long id;
    private String productOptionDescription;
    private BigDecimal optionPrice;
    private BigDecimal optionPriceForSmall;
    private BigDecimal optionPriceForNormal;
    private BigDecimal optionPriceForFamily;
    private BigDecimal optionPriceForParty;
    @ManyToOne
    @JoinColumn 
    private Product product;

    public ProductOption() {}
    public Long getId() {
        return id;
    }
    public void setId(Long id) {
        this.id = id;
    }
    public String getProductOptionDescription() {
        return productOptionDescription;
    }
    public void setProductOptionDescription(String productOptionDescription) {
        this.productOptionDescription = productOptionDescription;
    }
    public BigDecimal getOptionPrice() {
        return optionPrice;
    }
    public void setOptionPrice(BigDecimal optionPrice) {
        this.optionPrice = optionPrice;
    }
    public BigDecimal getOptionPriceForSmall() {
        return optionPriceForSmall;
    }
    public void setOptionPriceForSmall(BigDecimal optionPriceForSmall) {
        this.optionPriceForSmall = optionPriceForSmall;
    }
    public BigDecimal getOptionPriceForNormal() {
        return optionPriceForNormal;
    }
    public void setOptionPriceForNormal(BigDecimal optionPriceForNormal) {
        this.optionPriceForNormal = optionPriceForNormal;
    }
    public BigDecimal getOptionPriceForFamily() {
        return optionPriceForFamily;
    }
    public void setOptionPriceForFamily(BigDecimal optionPriceForFamily) {
        this.optionPriceForFamily = optionPriceForFamily;
    }
    public BigDecimal getOptionPriceForParty() {
        return optionPriceForParty;
    }
    public void setOptionPriceForParty(BigDecimal optionPriceForParty) {
        this.optionPriceForParty = optionPriceForParty;
    }

    public ProductOption(String productOptionDescription, BigDecimal optionPrice, BigDecimal optionPriceForSmall,
            BigDecimal optionPriceForNormal, BigDecimal optionPriceForFamily, BigDecimal optionPriceForParty) {
        super();
        this.productOptionDescription = productOptionDescription;
        this.optionPrice = optionPrice;
        this.optionPriceForSmall = optionPriceForSmall;
        this.optionPriceForNormal = optionPriceForNormal;
        this.optionPriceForFamily = optionPriceForFamily;
        this.optionPriceForParty = optionPriceForParty;
    }
    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + ((id == null) ? 0 : id.hashCode());
        result = prime * result + ((optionPrice == null) ? 0 : optionPrice.hashCode());
        result = prime * result + ((optionPriceForFamily == null) ? 0 : optionPriceForFamily.hashCode());
        result = prime * result + ((optionPriceForNormal == null) ? 0 : optionPriceForNormal.hashCode());
        result = prime * result + ((optionPriceForParty == null) ? 0 : optionPriceForParty.hashCode());
        result = prime * result + ((optionPriceForSmall == null) ? 0 : optionPriceForSmall.hashCode());
        result = prime * result + ((productOptionDescription == null) ? 0 : productOptionDescription.hashCode());
        return result;
    }
    @Override
    public boolean equals(Object obj) {
        if (this == obj)
            return true;
        if (obj == null)
            return false;
        if (getClass() != obj.getClass())
            return false;
        ProductOption other = (ProductOption) obj;
        if (id == null) {
            if (other.id != null)
                return false;
        } else if (!id.equals(other.id))
            return false;
        if (optionPrice == null) {
            if (other.optionPrice != null)
                return false;
        } else if (!optionPrice.equals(other.optionPrice))
            return false;
        if (optionPriceForFamily == null) {
            if (other.optionPriceForFamily != null)
                return false;
        } else if (!optionPriceForFamily.equals(other.optionPriceForFamily))
            return false;
        if (optionPriceForNormal == null) {
            if (other.optionPriceForNormal != null)
                return false;
        } else if (!optionPriceForNormal.equals(other.optionPriceForNormal))
            return false;
        if (optionPriceForParty == null) {
            if (other.optionPriceForParty != null)
                return false;
        } else if (!optionPriceForParty.equals(other.optionPriceForParty))
            return false;
        if (optionPriceForSmall == null) {
            if (other.optionPriceForSmall != null)
                return false;
        } else if (!optionPriceForSmall.equals(other.optionPriceForSmall))
            return false;
        if (productOptionDescription == null) {
            if (other.productOptionDescription != null)
                return false;
        } else if (!productOptionDescription.equals(other.productOptionDescription))
            return false;
        return true;
    }
    @Override
    public String toString() {
        return "ProductOption [id=" + id + ", productOptionDescription=" + productOptionDescription + ", optionPrice="
                + optionPrice + ", optionPriceForSmall=" + optionPriceForSmall + ", optionPriceForNormal="
                + optionPriceForNormal + ", optionPriceForFamily=" + optionPriceForFamily + ", optionPriceForParty="
                + optionPriceForParty + "]";
    }



}

這就是我初始化數據的方式。

@Component
public class WebsiteBootstrap implements ApplicationListener<ContextRefreshedEvent>{


    private ProductRepository productRepository;


    @Override
    public void onApplicationEvent(ContextRefreshedEvent arg0) {
        initProducts();
    }

    public WebsiteBootstrap( ProductRepository productRepository,
            ProductOptionRepository productOptionRepository) {
        this.productRepository=productRepository;
    }



    private void initProducts() {
        ProductOption productOpton1=new ProductOption("mit Cocktailsauce", new BigDecimal(0), null, null, null, null);

        ProductOption productOpton2=new ProductOption("mit Joghurtsauce", new BigDecimal(0), null, null, null, null);
        ProductOption productOpton3=new ProductOption("ohne Sauce", new BigDecimal(0), null, null, null, null);


        Product product37= new Product("Falafel", ProductCategory.Vegatarische_Döner, "Wahl aus: mit Cocktailsauce, mit Joghurtsauce oder ohne Sauce.",  new BigDecimal(5.00));

        product37.getProductOptions().add(productOpton1);
        product37.getProductOptions().add(productOpton2);
        product37.getProductOptions().add(productOpton3);


            this.productRepository.save(product37);


    }

在數據庫中我找不到product_id 。

我的映射中缺少什么？

Answer 1

ProductOptions在您的情況下是子實體（它包含帶有外鍵的列），因此它負責保存關系。 您必須在子端保存實體：

private void initProducts() {
    ProductOption productOpton1=new ProductOption("mit Cocktailsauce", new BigDecimal(0), null, null, null, null);
    ProductOption productOpton2=new ProductOption("mit Joghurtsauce", new BigDecimal(0), null, null, null, null);
    ProductOption productOpton3=new ProductOption("ohne Sauce", new BigDecimal(0), null, null, null, null);

    Product product37= new Product("Falafel", ProductCategory.Vegatarische_Döner, "Wahl aus: mit Cocktailsauce, mit Joghurtsauce oder ohne Sauce.",  new BigDecimal(5.00));

    product37.getProductOptions().add(productOpton1);
    product37.getProductOptions().add(productOpton2);
    product37.getProductOptions().add(productOpton3);

    productOpton1.setProduct(product37);
    productOpton2.setProduct(product37);
    productOpton3.setProduct(product37);

    this.productRepository.save(product37);
}