Jsonobject data guarantee order of fastjson

In the use of fastjson Of JSONObject Of put After the data , The sort will change , for example ：

public static void main(String[] args) throws Exception {
		JSONObject jsonObject = new JSONObject();
		jsonObject.put("b", "2222");
		jsonObject.put("a", "1111");
		jsonObject.put("d", "4444");
		jsonObject.put("c", "3333");
		String jsonString = jsonObject.toJSONString();
		System.out.println(jsonObject);
}

because JsonObject The default null parameter construction method is HashMap To store the , So the output is by key From the order of , If you want to make JsonObject In a fixed order （put The order of ） array , You can modify JsonObject The definition of HashMap Change it to LinkedHashMap

JSONObject jsonObject = new JSONObject(new LinkedHashMap<>());