将单个属性从类映射到其他类列表中的每个对象

Question

使用 MapStruct，我想将我的 RecipientDTO 映射到 Recipient。我希望 RecipientDTO 中的 AddressDTO 成为 Recipient.subscriptions 的每个订阅中的地址。如何使用 MapStruct 实现此目的？我的课程是这样的：

public class AddressDTO {
    String street;
    String city;
}

public class SubscriptionDTO {
    String category;
}

public class RecipientDTO {
    String name;
    AddressDTO address;
    List<SubscriptionDTO> subscriptions;
}

public class Address {
    String street;
    String city;
}

public class Subscription {
    Address address;
    String category;
}

public class Recipient {
    String name;
    List<Subscription> subscriptions;
}

我尝试为订阅指定一个单独的映射器接口。所以

@Mapper
public interface SubscriptionMapper {
  SubscriptionMapper INSTANCE = Mappers.getMapper(SubscriptionMapper.class);

  @Mapping(target = "address", source = "addressDTO")
  Subscription toSubscription(SubscriptionDTO dto, AddressDTO addressDTO);
}

这将生成一个用于订阅的映射器。

但是当我这样做时

@Mapper(uses = SubscriptionMapper.class)
public interface RecipientMapper {
  RecipientMapper INSTANCE = Mappers.getMapper(RecipientMapper.class);


  Recipient toRecipient(RecipientDTO recipientDTO);
}

它不会使用来自 SubscriptionMapper 的带有额外参数的映射方法。

如果可能的话我想做这样的事情：

@Mapping(target = "subscriptions.address", source = "address")
Recipient toRecipient(RecipientDTO recipientDTO);

Answer 1

您需要使用@AfterMapping注释。此注释允许您在标准映射过程之后添加自定义代码。

@Mapper
public interface RecipientMapper {
    RecipientMapper INSTANCE = Mappers.getMapper(RecipientMapper.class);

    Recipient toRecipient(RecipientDTO recipientDTO);

    @AfterMapping
    default void updateAddresses(RecipientDTO recipientDTO, @MappingTarget Recipient recipient) {
        if(Objects.nonNull(recipient) && !CollectionUtils.isEmpty(recipient.getSubscriptions())){
            recipient.getSubscriptions().forEach(rcpt -> {
                var address = recipientDTO.getAddress();
                rcpt.setAddress(Address.builder().city(address.getCity()).street(address.getStreet()).build());
            });
        }
    }
}