I am trying to use the Class-based Projections to fill the data but seems the Spring JPA does not support the nested projection. Here is my entity class:
public class Category extends BaseEntity<String> {
@Column(unique = true)
private String code;
private String externalCode;
@ManyToOne(cascade = CascadeType.ALL)
private Category parent;
..
}
Here is the DTO class for same:
@Data
@NoArgsConstructor
@AllArgsConstructor
@Builder
public class CategoryDto implements BaseDto, Serializable {
private String code;
private String externalCode;
private CategoryDto parent;
..
}
My CategoryRepository
@Query("select new com.easycart.core.data.category.CategoryDto(c.id,c.code,c.externalCode,c.seoMeta, c.createdAt, c.updatedAt,c.parent) FROM Category c where c.code = :code")
CategoryDto findCategoryByCode(String code);
I can't use the c.parent as the type is Category and not the CategoryDto, also I did not find any option to use the nested projection to fill the parent information for the given entity. Can someone help me with following questions?
- Is there a way to achieve this using class based projection?
- DO I need to fallback to the option to fill the parent information separately (I don't need lot of information for the parent in the initial load.).
- Any other way to achieve this? I don't want to use the interface based projection as initial test showing it's very slow as compare to class based projection.
