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javajsonobjectjson-simple

How to get the values from keys in nested objects using only json-simple


I want to get only a specific value out of all the nested objects. In the application I just need the msg 3 which is inside another object messages.

I have tried it using JSONObject but it is not working for nested object. However It is working with just a single object means root object .

INPUT - {"name":"lola","messages":{"msg 1":"msg 2","msg 3":"msg 4"},"age":22}

        String s = sc.nextLine();
        JSONParser parser = new JSONParser(); 
        JSONObject json = (JSONObject) parser.parse(s);
        System.out.println(json);
        Object name = json.get("messages");
        System.out.println(name);

        JSONObject messageObject = (JSONObject) json.get("messages");
        System.out.println(employeeObject);
        //Get employee first name
        String msg= (String) messageObject.get("msg3");   
        System.out.println(msg);

The Output:

{"msg 3":"msg 4","msg 1":"msg 2"}
{"msg 3":"msg 4","msg 1":"msg 2"}
null

The last nested object is not fetching in any way. Another thing is that the normal print of the string as a JSONObject gets changed. like the msg3 came before msg1. In place of null - msg4 should be there.

Thanks in advance.


Solution

  • You are missing a space between "msg" and "3". By the way - you can do this easier, as such.

    String s = sc.nextLine();
    JSONParser parser = new JSONParser(); 
    JSONObject json = (JSONObject) parser.parse(s);
    System.out.println(json);
    System.out.println(json.get("message").get("msg 3"));