One 、 Test data preparation
List<Map<String, String>> result = new ArrayList();
Map<String, String> map = new HashMap<>();
map.put("san", " Zhang San ");
map.put("si", " Li Si ");
map.put("wu", " Wang Wu ");
map.put("wang", " Lao Wang ");
map.put("lao", " Lao zhang ");
result.add(map);
Two 、 take list<Map<String, String>> The structural data of is converted into json Array
JSONArray jsonArray = JSONArray.parseArray(JSONArray.toJSON(result).toString());
System.out.println(jsonArray);
give the result as follows ：
-------------------------------------------------------------------------------------------------
--------------[{"san":" Zhang San ","wang":" Lao Wang ","si":" Li Si ","lao":" Lao zhang ","wu":" Wang Wu "}]-------------------
-------------------------------------------------------------------------------------------------
3、 ... and 、 obtain json The array corresponds to key Value
// 1. First, traverse the data
for (Object o : jsonArray) {
// 2. Then object Turn into JsonObject type
JSONObject jsonObject = (JSONObject) JSONObject.parse(JSON.toJSONString(o));
// 3. Finally, according to the corresponding key Get the corresponding value value
System.out.println(jsonObject.get("san"));
System.out.println(jsonObject.get("wang"));
System.out.println(jsonObject.get("si"));
System.out.println(jsonObject.get("lao"));
System.out.println(jsonObject.get("wu"));
} give the result as follows ：
---------------------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------
------------------------------ Zhang San Lao Wang Li Si Lao zhang Wang Wu -----------------------------------------
---------------------------------------------------------------------------------------------------
---------------------------------------------------------------------------------------------------
Four 、 call Entry Object getkey() and getValue() Method to get the key value
According to... In the data key obtain value More articles on value
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