java - 在不知道 key 的情况下解析 json

Question

我正在尝试在不知道 json 格式的键和结构的情况下在 java 中解析 json，并将该数据保存到 hashmap 中

我将如何遍历整个 json 格式并将键和值存储到 hashmap 中

 {"id" : 12345, "value" : "123", "person" : "1"}

就像在这个例子中，所有的键都是jsonobject，没有一个是json数组

还有一些其他的库，比如 jackson，我不想使用任何第三方库

Answer 1

这只是一个例子。对于像

这样的 JSON

{
 "status": "OK",
 "search_result": [

            {
                "product": "abc",
                "id": "1132",
                "question_mark": {
                    "141": {
                        "count": "141",
                        "more_description": "this is abc",
                        "seq": "2"
                    },
                    "8911": {
                        "count": "8911",
                        "more_desc": "this is cup",
                        "seq": "1"
                    }
                },
                "name": "some name",
                "description": "This is some product"
            },
            {
                "product": "XYZ",
                "id": "1129",
                "question_mark": {
                    "379": {
                        "count": "379",
                        "more_desc": "this is xyz",
                        "seq": "5"
                    },
                    "845": {
                        "count": "845",
                        "more_desc": "this is table",
                        "seq": "6"
                    },
                    "12383": {
                        "count": "12383",
                        "more_desc": "Jumbo",
                        "seq": "4"
                    },
                    "257258": {
                        "count": "257258",
                        "more_desc": "large",
                        "seq": "1"
                    }
                },
                "name": "some other name",
                "description": "this is some other product"
            }
       ]
}

使用 JSONObject keys() 获取键，然后迭代每个键以获取动态值。

代码大致如下:

// searchResult refers to the current element in the array "search_result"
JSONObject questionMark = searchResult.getJSONObject("question_mark");
Iterator keys = questionMark.keys();

while(keys.hasNext()) {
    // loop to get the dynamic key
    String currentDynamicKey = (String)keys.next();

    // get the value of the dynamic key
    JSONObject currentDynamicValue = questionMark.getJSONObject(currentDynamicKey);

    // do something here with the value...
}

也试试这段代码

public void parse(String json)  {
   JsonFactory factory = new JsonFactory();

   ObjectMapper mapper = new ObjectMapper(factory);
   JsonNode rootNode = mapper.readTree(json);  

   Iterator<Map.Entry<String,JsonNode>> fieldsIterator = rootNode.fields();
   while (fieldsIterator.hasNext()) {

       Map.Entry<String,JsonNode> field = fieldsIterator.next();
       System.out.println("Key:"field.getKey() + "\tValue:" + field.getValue());
   }

也看看这个链接

https://github.com/alibaba/fastjson