看来这
@JsonUnwrapped就是我所需要的。
https://www.baeldung.com/jackson-
annotations
@JsonUnwrapped 定义在序列化/反序列化时应该解包/展平的值。
让我们确切地了解它是如何工作的。我们将使用注释解开属性名称：
public class UnwrappedUser { public int id; @JsonUnwrapped public Name name; public static class Name { public String firstName; public String lastName; } }现在让我们序列化此类的实例：
@Testpublic void whenSerializingUsingJsonUnwrapped_thenCorrect() throws JsonProcessingException, ParseException { UnwrappedUser.Name name = new UnwrappedUser.Name("John", "Doe"); UnwrappedUser user = new UnwrappedUser(1, name); String result = new ObjectMapper().writevalueAsString(user); assertThat(result, containsString("John")); assertThat(result, not(containsString("name")));}输出是这样的-静态嵌套类的字段与其他字段一起展开：
{ "id":1, "firstName":"John", "lastName":"Doe"}
因此，它应该类似于：
public class TrasactionDTO { private List<Item> items; ...}public static class Item { @JsonUnwrapped private InnerItem innerItem; ...}public static class InnerItem { private String itemNumber; ...}
