mapstruct-List 到List

Question

我在DTO中有一个字符串列表，我想将其映射到对象列表中，在映射器中，我使用该服务通过此字符串获取对象，但是我遇到以下错误

无法将属性“ java.util.List客户”映射到“ java.util.List客户”。

考虑声明/实现映射方法：“ java.util.Listmap（java.util.List value）“。

public class FirstDomain implements Serializable {

    private static final long serialVersionUID = 1L;

    @Id
    private String  id;

    private String description;

    private List<Customer> customers;
}

public class FirstDomainDTO {

    private String id;

    private String description;

    private List<String> customers;
}

@Mapper(uses = { CustomerService.class })
public interface FirstDomainMapper extends EntityMapper<FirstDomainDTO, FirstDomain> {

    @Mapping(source = "customers", target = "customers")
    FirstDomainDTO toDto(FirstDomain firstDomain);

    @Mapping(source = "customers", target = "customers")
    FirstDomain toEntity(FirstDomainDTO firstDomainDTO);

    default String fromCustomer(Customer customer) {
        return customer == null ? null : customer.getCode();
    }

}

Answer 1

通用类型不固定化（但是将来会使用），因此MapStruct无法理解如何映射两个列表。您唯一的选择是使用自定义映射方法。

@Named("CustomersMapping")
public class CustomersMapping {
  @Named("StringToCustomer")
  public List<Customer> toCustomers(final List<String> customers) {
    ...
  }

  @Named("CustomerToString")
  public List<String> toStrings(final List<Customer> customers) {
    ...
  }
}

和

@Mapper(uses = { CustomerMapping.class })
public interface FirstDomainMapper extends EntityMapper<FirstDomainDTO, FirstDomain> {
  @Mapping(source = "customers", target = "customers", qualifiedByName = { "CustomersMapping", "CustomerToString" })
  FirstDomainDTO toDto(final FirstDomain firstDomain);

  @Mapping(source = "customers", target = "customers", qualifiedByName = { "CustomersMapping", "StringToCustomer" })
  FirstDomain toEntity(final FirstDomainDTO firstDomainDTO);
}