无法将含@字段的JSON转换为自定义Java对象，求解决方案

我的Java代码 #

BookRequestTO类 #

@Getter
@Builder
@EqualsAndHashCode
@ToString
@NoArgsConstructor
@AllArgsConstructor
public class BookRequestTO {
    private String id;

    @NotNull(message = Constants.FUNCTION_NULL)
    @Valid
    private BookInfo function;

    private List<String> parameters;
}

BookInfo类 #

@Getter
@Builder
@EqualsAndHashCode
@ToString
@NoArgsConstructor
@AllArgsConstructor
public class BookInfo {

    @NotEmpty(message = Constants.TYPE_NULL)
    @JsonProperty(value = "@type")
    private String type;

    @NotEmpty(message = Constants.ACTION_NULL)
    private String name;
}

尝试的两种方案及问题 #

方案1：使用Jackson的ObjectMapper #

import com.google.gson.Gson;
import org.json.JSONArray;
import org.json.JSONObject;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;

JSONObject jsonRequest = new JSONObject();
jsonRequest.put("@type", "education");
jsonRequest.put("name", "Geography");

JSONObject bookRequestToJson = new JSONObject();
bookRequestToJson.put("id", "1234");
bookRequestToJson.put("function", jsonRequest);
bookRequestToJson.put("parameters", new JSONArray());

BookRequestTO bookRequestTO = new ObjectMapper().readValue(bookRequestToJson.toString(), BookRequestTO.class);

System.out.println("BEFORE ObjectWriter: bookRequestTO " + bookRequestTO);

执行输出：

BEFORE ObjectWriter: bookRequestTO BookRequestTO(id=1234, function=BookInfo(type=education, name=Geography), parameters=[])

这里@type字段已经映射到Java对象的type属性，但我误以为输出应该显示@type=education，不确定映射是否真的正确。

方案2：结合ObjectWriter与Gson #

ObjectWriter ow1 = new ObjectMapper().writer().withDefaultPrettyPrinter();
String request = ow1.writeValueAsString(bookRequestToJson.toString()).replaceAll("\\\\", "");
request = request.substring(1, request.length() - 1);
System.out.println("AFTER ObjectWriter: bookRequestTO " + request);
        
BookRequestTO bookRequestTO1 = new Gson().fromJson(request, BookRequestTO.class);
System.out.println("AFTER Gson: bookRequestTO " + bookRequestTO1);

执行输出：

AFTER ObjectWriter: bookRequestTO {"function":{"@type":"education","name":"Geography"},"id":"1234","parameters":[]}
AFTER Gson: bookRequestTO BookRequestTO(id=1234, function=BookInfo(type=null, name=Geography), parameters=[])

这里用Gson转换后，BookInfo的type属性为null，没有正确映射@type字段。

疑问 #

请问如何正确实现含@字段的JSON到Java自定义对象的转换？Java是否支持此类映射？

内容的提问来源于stack exchange，提问作者user19817822