如何忽略一个 class 中另一个 class 的任何字段？

Question

I mean, for example I have ProductDTO and OrderDetail classes. I want to ignore price field on json because price is changeable and I want keep price for buy. This is my ProductDTO:

public class ProductDTO {

    String id;
    String name;
    String description;
    int price; //I want to ignore this one
    String brand;
    String size;
    int stockCount;
    String type;
    String color;
    String gender;
}

And this is my OrderDetail class:

public class OrderDetail {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    Long id;
    int price;
    ProductDTO productDTO;
}

Answer 1

first of all,we never put a price in integer, it's a double or a bigDecimal. secondly, we never put a DTO in an entity. DTO is a design pattern that allows data transfer without impacting the entity.

For your problem, it's a simple mapping point between DTO and entity. use a mapper either by manual method implementation or by using a mapper generated code like MapStruct.

For example you want to ignore the price like this:

@Mapper(componentModel = "spring")
public interface ProductMapper {
    
    @Mappings({
        @Mapping(source = "idDTO", target = "id"),
        @Mapping(source = "price", target = "price", ignore = true),
        @Mapping(source = "idArriveePar", target = "idArrivePar"),
    })
    Product toEntity(ProductDTO productDTO);
}

this would ignore the price as you want.

Hope this would be helpfull