mapstruct-列表到列表

Question

我的DTO中有一个字符串列表，我想把它映射成一个对象列表，在映射器中我使用服务通过这个字符串获取对象，但我有以下错误

考虑声明/实现一个映射方法：“java.util.list map(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

您得到的错误信息应该足以帮助您理解问题所在。在这种情况下，MapStruct不知道如何从列表 映射到列表 。相反的方式是可以的，因为您已经定义了

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

要解决这个问题，还需要定义反向。

@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();
    }

    default Customer fromStringToCustomer(String customerId) {
        // Implement your custom mapping logic here
    }
}