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JPA - Join another entity by EmbeddedId with 2 columns

Basically. I have a ProductEntity, like this:

@Entity
@Table(name = "product", schema = "shop")
public class ShopProductEntity {

@EmbeddedId
private ProductEntityId id;

@Column(name = "product_name")
private String name;

@Column(name = "product_category_id")
private int categoryId;

@Column(name = "product_language_id")
private int languageId;

// TODO: Get category by categoryId and languageId.
private CategoryEntity category;


I have another CategoryIdentity:

@Entity
@Table(name = "category", schema = "shop")
public class CategoryEntity {

@EmbeddedId
private CategoryEntityId id;

@Column(name = "category_name")
private String name;

@Column(name = "category_url")
private String url;


It has an EmbeddedId like this:

@Embeddable
public class CategoryEntityId implements Serializable {
@Column(name = "category_id", nullable = false)
private int categoryId;

@Column(name = "language_id", nullable = false)
private int languageId;

public int getCategoryId() {
return categoryId;
}

public int getLanguageId() {
return languageId;
}


Now, every product has a category. Categories are unique by their id and language. The shop connects to a category by both the categoryId and languageId columns. How do I add the CategoryEntity to my ProductEntity so I can use the category's url value for my product?

I tried adding this to ShopProductEntity:

@ManyToOne
@JoinColumns({
@JoinColumn(name="categoryId", referencedColumnName="categoryId"),
@JoinColumn(name="languageId", referencedColumnName="languageId"),
})
private CategoryEntity category;


@ManyToOne ShopProductEntity.category

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