我在产品和类别类之间有一对多的关系，我想添加带有从jsp页面中选择的category_id的产品，但是当此代码运行时类别表更新为null 的 的
的@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name="productId")
private int productId;
@NotEmpty
@Column(name="productName",unique=true)
private String productName;
@NotEmpty
@Column(name="description")
private String description;
@Column(name="price")
private int price;
@JoinColumn(name = "category_id")
@ManyToOne(cascade = CascadeType.ALL)
Category category;
@OneToMany(mappedBy="product")
Collection<OrderedProduct> orderedProductCollection;
public Collection<OrderedProduct> getOrderedProductCollection() {
return orderedProductCollection;
}
public void setOrderedProductCollection(
Collection<OrderedProduct> orderedProductCollection) {
this.orderedProductCollection = orderedProductCollection;
}
public int getProductId() {
return productId;
}
public void setProductId(int productId) {
this.productId = productId;
}
public String getProductName() {
return productName;
}
public void setProductName(String productName) {
this.productName = productName;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public int getPrice() {
return price;
}
public void setPrice(int price) {
this.price = price;
}
public Category getCategory() {
return category;
}
public void setCategory(Category category) {
this.category = category;
}
}
的 的 的
的@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Basic(optional = false)
@Column(name="categoryId")
private int categoryId;
@Column(name="categoryName")
private String categoryName;
@OneToMany(mappedBy="category")
private List<Product> productlist=new ArrayList<Product>();
public Category() {
super();
}
public Category(int categoryId) {
super();
this.categoryId = categoryId;
}
public Category(int categoryId, String categoryName) {
super();
this.categoryId = categoryId;
this.categoryName = categoryName;
}
public int getCategoryId() {
return categoryId;
}
public void setCategoryId(int categoryId) {
this.categoryId = categoryId;
}
public String getCategoryName() {
return categoryName;
}
public void setCategoryName(String categoryName) {
this.categoryName = categoryName;
}
public List<Product> getProductlist() {
return productlist;
}
public void setProductlist(List<Product> productlist) {
this.productlist = productlist;
}}
的
的
的public ModelAndView addProduct(@Valid OperationService operationService,BindingResult result,ModelMap model,ModelAndView mav)
{
if(result.hasErrors())
{
mav.setViewName("addProduct");
return mav;
}
operationService.getProduct().setCategory(operationService.getCategory());
productRepository.save(operationService.getProduct());
mav.setViewName("success");
return mav;
}
的
的
的 public class OperationService {
Customer customer;
CustomerCart customerCart;
OrderedProduct orderedProduct;
Product product;
Category category;
public Customer getCustomer() {
return customer;
}
public void setCustomer(Customer customer) {
this.customer = customer;
}
public CustomerCart getCustomerCart() {
return customerCart;
}
public void setCustomerCart(CustomerCart customerCart) {
this.customerCart = customerCart;
}
public OrderedProduct getOrderedProduct() {
return orderedProduct;
}
public void setOrderedProduct(OrderedProduct orderedProduct) {
this.orderedProduct = orderedProduct;
}
public Product getProduct() {
return product;
}
public void setProduct(Product product) {
this.product = product;
}
public Category getCategory() {
return category;
}
public void setCategory(Category category) {
this.category = category;
}}
的 这里是jsp页面，选择category_id表单类别表的值
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Add Product</title>
</head>
<body>
<form:form action="AddProduct" method="post" commandName="operationService">
<form:select path="category.categoryId">
<c:forEach var="cate" items="${allCategory}">
<form:option value="${cate.categoryId}" id="{cate.categoryId}">
${cate.categoryName}</form:option>
</c:forEach>
</form:select>
33<form:input path="product.productName"/>
44<form:input path="product.description"/>
55<form:input path="product.price"/>
<input type="submit">
</form:form>
<a href="AddCategory">Add Category</a>
</body>
</html>
</i>
答案 0 :(得分：1)
我猜你错过了对存储库的flush（）调用。试试这个：
productRepository.save(operationService.getProduct());
productRepository.flush();