如何創建一個字段數未知的 JSON？

Question

我需要轉換這樣的結構：

List<String> fields;

像這樣到 JSON ：

{
   "field1": "data1",
   "field2": "data2",
   "field3": "data3",
   ...
}

我怎樣才能做到這一點？

UPD：列表包含值，如下所示：

List<String> fields = List.of("data1", "data2", "data3");

Answer 1

ObjectNode objectNode = new ObjectMapper().createObjectNode();
List<String> fields = new ArrayList<>();
fields.add("data1");
fields.add("data2");
fields.add("data3");
for (int i = 0; i < fields.size(); i++) {
    objectNode.put("field" + (i+1), fields.get(i));
}
System.out.println(objectNode.toPrettyString());

Output

{
  "field1" : "data1",
  "field2" : "data2",
  "field3" : "data3"
}

Answer 2

您可以使用 map 集合Map<String,Object> ：

Map<String,Object> mapp = new HashMap<>();
mapp.put("field1", "data1");
mapp.put("field2", "data2");
mapp.put("field3", "data3");
mapp.put("field4", "data4");
JSONObject json = new JSONObject(mapp);
System.out.println(json);

output：

{
  "field1":"data1",
  "field3":"data3",
  "field2":"data2",
  "field4":"data4"
}