打印键值无法与JSONObject一起正常工作

Question

I'm trying to print out all the key values in the JSON below but for whatever reason its only printing the first set array of values for me.

How can i make it that all the key values in the idValue String are printed out?

Edit: I'm now getting the error:

Unexpected Error : JSONObject["submenu"] not a string.

Code

import com.google.common.collect.LinkedListMultimap;
import com.google.common.collect.Multimap;
import org.json.JSONArray;
import org.json.JSONObject;

import java.util.Map;

public class testing {
    static Multimap<String, String> allMappedKeyValues = LinkedListMultimap.create();

    public static void main(String[] args) {

        String idValue = "[{\"link\": \"/us_new/en/home\",\"amid\": \"1__home\",\"title\": \"Home\"}, {\"link\": \"/us_new/en/home/diagnosis\",\"amid\": \"2__diagnosis\",\"title\": \"Diagnosis\"}, {\"link\": \"/us_new/en/home/loss\",\"amid\": \"3__loss\",\"title\": \"loss\",\"submenu\": [{\"amid\": \"4__quiz\",\"name\": \"quiz\",\"title\": \"quiz\"},{\"amid\": \"5__questions\",\"name\": \"questions\",\"title\": \"Questions\"}]}]";

        JSONArray array = new JSONArray(idValue);
        for (int i = 0; i < array.length(); i++)
        {
            JSONObject object = array.getJSONObject(i);
            JSONArray keys = object.names();

            for (int j = 0; j < keys.length(); ++j)
            {
                String key = keys.getString(j);
                Object value = object.get(key);

                if (value instanceof JSONArray) {

                    JSONArray array1 = (JSONArray) value;

                    for (int k = 0; k < array1.length(); k++) {
                        JSONObject object1 = array1.getJSONObject(k);

                        JSONArray keys1 = object1.names();

                        String key2 = keys1.getString(k);
                        String value2 = object1.getString(key2);
                        String title2 = object1.getString("title");
//                        System.out.println("-key :" + key2 + "\n-value " + value2 + "\n-title :" + title2);

                        if (key2.contains("amid")) {
                            allMappedKeyValues.put(value2 + "__title", title2);
                        }
                    }
                } else {
                    String key1 = keys.getString(j);
                    String value1 = object.getString(key1);
                    String title1 = object.getString("title");
//                    System.out.println("-key :" + key1 + "\n-value " + value1 + "\n-title :" + title1);

                    if (key.equals("amid")) {
                        allMappedKeyValues.put(value1 + "__title", title1);
                    }
                }
            }
        }

        for (Map.Entry<String, String> entry : allMappedKeyValues.entries()) {
            System.out.println("This is the key-" + entry.getKey() + " value-" + entry.getValue());
        }
    }
}

JSON

[{"link": "/us_new/en/home","amid": "1__home","title": "Home"}, {"link": "/us_new/en/home/diagnosis","amid": "2__diagnosis","title": "Diagnosis"}, {"link": "/us_new/en/home/loss","amid": "3__loss","title": "loss","submenu": [{"amid": "4__quiz","name": "quiz","title": "quiz"},{"amid": "5__questions","name": "questions","title": "Questions"}]}]

Output

  Entered loop :0
-key :link
-value /us_new/en/home
-title :Home
Entered loop :1
-key :amid
-value 1__home
-title :Home
Entered loop :2
-key :title
-value Home
-title :Home

Answer 1

You don't need to replace [] , your JSON is in correct format. You can actually create JSONArray directly from the String,

String idValue = "[{\"link\":\"/us_new/en/home\",\"amid\":\"1__home\",\"title\":\"Home\"},{\"link\":\"/us_new/en/home/diagnosis\",\"amid\":\"2__diagnosis\",\"title\":\"Diagnosis\"},{\"link\":\"/us_new/en/home/treatment\",\"amid\":\"3__loss\",\"title\":\"loss\"}]";
JSONArray objects = new JSONArray(idValue);
for(int i = 0; i < objects.length(); i++) {
    JSONObject jsonObject = objects.getJSONObject(i);

    Iterator<String> keys = jsonObject.keys();
    while(keys.hasNext()) {
        String key = keys.next();
        System.out.printf("key : %s | value : %s\n", key, jsonObject.get(key));
    }
}

Output :

key : link | value : /us_new/en/home
key : amid | value : 1__home
key : title | value : Home
key : link | value : /us_new/en/home/diagnosis
key : amid | value : 2__diagnosis
key : title | value : Diagnosis
key : link | value : /us_new/en/home/treatment
key : amid | value : 3__loss
key : title | value : loss

Answer 2

you can use following recursive function "parseJsonArray" to parse your nested jsonArrays.

String idValue = "[{\"link\": \"/us_new/en/home\",\"amid\": \"1__home\",\"title\": \"Home\"}, {\"link\": \"/us_new/en/home/diagnosis\",\"amid\": \"2__diagnosis\",\"title\": \"Diagnosis\"}, {\"link\": \"/us_new/en/home/loss\",\"amid\": \"3__loss\",\"title\": \"loss\",\"submenu\": [{\"amid\": \"4__quiz\",\"name\": \"quiz\",\"title\": \"quiz\"},{\"amid\": \"5__questions\",\"name\": \"questions\",\"title\": \"Questions\"}]}]";

parseJsonArray(idValue);

private void parseJsonArray(String jsonString) throws JSONException {
    System.out.println("jsonString: " + jsonString);

    JSONArray objects = new JSONArray(jsonString);
    JSONArray  nestedJsonArray;
    JSONObject  nestedJsonObject;

    for(int i = 0; i < objects.length(); i++) {
        JSONObject jsonObject = objects.getJSONObject(i);
        Iterator<String> keys = jsonObject.keys();

        while(keys.hasNext()) {
            String key = keys.next();                
            Object nestedObject = jsonObject.get(key);
            if (nestedObject instanceof JSONArray) {
                System.out.println("it's an array: " + key);
                nestedJsonArray = (JSONArray)nestedObject;
                parseJsonArray(nestedJsonArray.toString());
            }
            else if (nestedObject instanceof JSONObject) {
                nestedJsonObject = (JSONObject)nestedObject;
                System.out.printf("key : %s | value : %s | title : %s\n", key, nestedJsonObject.getString(key), nestedJsonObject.getString("title"));
            }
            else {
                System.out.printf("key : %s | value : %s | title : %s\n", key, jsonObject.getString(key), jsonObject.getString("title"));
            }
        }
    }

Answer 3

You only read the first JSON object ( {\\"link\\":\\"/us_new/en/home\\",\\"amid\\":\\"1__home\\",\\"title\\":\\"Home\\"} ). In order to read all 3 objects, first change the JSON String to an array (add the missing [ and ] ):

String idValue = "[{\"link\":\"/us_new/en/home\",\"amid\":\"1__home\",\"title\":\"Home\"},{\"link\":\"/us_new/en/home/diagnosis\",\"amid\":\"2__diagnosis\",\"title\":\"Diagnosis\"},{\"link\":\"/us_new/en/home/treatment\",\"amid\":\"3__loss\",\"title\":\"loss\"}]";

Then iterate over the array:

JSONArray array = new JSONArray(idValue);
for (int i = 0; i < array.length (); i++) {
    JSONObject object = array.getJSONObject (i);
    JSONArray keys = object.names();
    for (int j = 0; j < keys.length(); ++j) {
        System.out.println("Entered loop :"+j);
        String key = keys.getString(j);
        String value = object.getString(key);
        String title = object.getString("title");
        System.out.println("-key :" + key + "\n-value " + value + "\n-title :" + title);
    }
}

Output:

Entered loop :0
-key :link
-value /us_new/en/home
-title :Home
Entered loop :1
-key :amid
-value 1__home
-title :Home
Entered loop :2
-key :title
-value Home
-title :Home
Entered loop :0
-key :link
-value /us_new/en/home/diagnosis
-title :Diagnosis
Entered loop :1
-key :amid
-value 2__diagnosis
-title :Diagnosis
Entered loop :2
-key :title
-value Diagnosis
-title :Diagnosis
Entered loop :0
-key :link
-value /us_new/en/home/treatment
-title :loss
Entered loop :1
-key :amid
-value 3__loss
-title :loss
Entered loop :2
-key :title
-value loss
-title :loss