Update the Foreign Key with JPA - spring

Question

I created 2 entities :
#Entity
#Table(name="products")
public class ProductEntity {
#Id
#GeneratedValue(strategy= GenerationType.IDENTITY)
private Long id;
#Column(nullable = false)
private String productKeyId;
// many to one relationship with category
#ManyToOne
#JoinColumn(name = "category_id")
private CategoryEntity category;
#Column(nullable = false)
private String name;
#Column(nullable = false)
private double price;
#Column(nullable = false)
private int qty;
private String imgPath;
// getters & setters
}
And :
#Entity
#Table(name="categories")
public class CategoryEntity {
#Id
#GeneratedValue(strategy= GenerationType.IDENTITY)
private Long id;
#Column(length = 30, nullable = false)
private String categoryKeyId;
#Column(nullable = false)
private String name;
#ManyToOne(optional = true, fetch = FetchType.LAZY)
#JoinColumn(name="parent_id", nullable=true)
private CategoryEntity parentCategory;
// allow to delete also subcategories
#OneToMany(mappedBy="parentCategory", cascade = CascadeType.ALL)
private List<CategoryEntity> subCategories;
//Here mappedBy indicates that the owner is in the other side
#OneToMany(fetch = FetchType.EAGER, mappedBy = "category", cascade = CascadeType.REMOVE)
private List<ProductEntity> products;
}
I have datas in the database generated :
Here is my Product table
And the category table
My issue is the following. I use a REST API to update the product and the category (if needed).
{
"name": "Pizza12",
"price": 25.0,
"qty": 15,
"imgPath": "anotherpathImage",
"category": {
"categoryKeyId": "VMz7EM6tNfoOAQtO1SHPYcH14jj0Cy",
"name": "Fish"
}
}
In my service I try to update both part separatelly :
#Override
public ProductDto updateProduct(String productKeyId, ProductDto productDto) {
// create a return object of type Product
ProductDto returnValue = new ProductDto();
// create Entity objects to request on the database
ProductEntity productEntity = productRepository.findByProductKeyId(productKeyId);
CategoryEntity categoryEntity = categoryRepository.findCategoryEntityByProductKeyId(productKeyId);
ModelMapper modelMapper = new ModelMapper();
if (productEntity == null)
throw new ApplicationServiceException(ErrorMessages.NO_RECORD_FOUND.getErrorMessage());
productEntity.setProductKeyId(productKeyId);
productEntity.setName(productDto.getName());
productEntity.setPrice(productDto.getPrice());
productEntity.setQty(productDto.getQty());
productEntity.setImgPath(productDto.getImgPath());
// update the category
CategoryEntity updatedCategory = categoryRepository.save(categoryEntity);
productEntity.setCategory(updatedCategory);
// productEntity.setCategory(categoryEntity);
System.out.println("product entity : " + productEntity.toString());
ProductEntity updatedProduct = productRepository.save(productEntity);
updatedProduct.setCategory(updatedCategory);
returnValue = modelMapper.map(updatedProduct, ProductDto.class);
return returnValue;
}
Unfortunatelly, it doesn't seem to work as expected. The product is updated, the category remains the same.

Answer 1

I finally solved my Issue thanks to Janar and Repoker.
#Override
public ProductDto updateProduct(String productKeyId, ProductDto productDto) {
// create a return object of type Product
ProductDto returnValue = new ProductDto();
// create Entity objects to request on the database
ProductEntity productEntity = productRepository.findByProductKeyId(productKeyId);
CategoryEntity categoryEntity = categoryRepository.findByCategoryKeyId(productDto.getCategory().getCategoryKeyId());
//CategoryEntity categoryEntity = categoryRepository.findCategoryEntityByProductKeyId(productKeyId);
ModelMapper modelMapper = new ModelMapper();
if (productEntity == null)
throw new ApplicationServiceException(ErrorMessages.NO_RECORD_FOUND.getErrorMessage());
productEntity.setProductKeyId(productKeyId);
productEntity.setName(productDto.getName());
productEntity.setPrice(productDto.getPrice());
productEntity.setQty(productDto.getQty());
productEntity.setImgPath(productDto.getImgPath());
// update the category
CategoryEntity updatedCategory = categoryRepository.save(categoryEntity);
productEntity.setCategory(productEntity.getCategory());
// productEntity.setCategory(categoryEntity);
System.out.println("product entity : " + productEntity.toString());
ProductEntity updatedProduct = productRepository.save(productEntity);
updatedProduct.setCategory(updatedCategory);
returnValue = modelMapper.map(updatedProduct, ProductDto.class);
return returnValue;
}
I was not persisting the new values entered but the values that were initially set...