pass a JsonArray to an ArryList

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pass a JsonArray to an ArryList

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#1 by (1 votes)

0

I have the following code:

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.Iterator;
import org.json.JSONArray;
import org.json.JSONObject;

public class Test {

public static void main(String[] args) {
    try {
        Test.call_me();
    } catch (Exception e) {
        e.printStackTrace();
    }
}

public static void call_me() throws Exception {
    String url = "https://www.googleapis.com/youtube/v3/videos?id=Ald6YIXwiyI&key=AIzaSyBMHhfr4Crs6OvrV7nEnWWSF7bmRDHkgOg&part=statistics&fields=items(id,statistics)";
    URL obj = new URL(url);
    HttpURLConnection con = (HttpURLConnection) obj.openConnection();
    // optional default is GET
    con.setRequestMethod("GET");
    //add request header
    con.setRequestProperty("User-Agent", "Mozilla/5.0");
    int responseCode = con.getResponseCode();
    System.out.println("\nSending 'GET' request to URL : " + url);
    System.out.println("Response Code : " + responseCode);
    BufferedReader in = new BufferedReader(
            new InputStreamReader(con.getInputStream()));
    String inputLine;
    StringBuffer response = new StringBuffer();
    while ((inputLine = in.readLine()) != null) {
        response.append(inputLine);
    }
    in.close();
    //print in String
    //System.out.println(response.toString());
    //Read JSON response and print

    JSONObject myResponse = new JSONObject(response.toString());
    //System.out.println(response.toString());
    System.out.println(myResponse.toString());
    JSONObject items = new JSONObject(myResponse.getJSONArray("items").getJSONArray(0));

Now this generates a Json of the following format:

{"items":[{"id":"Ald6YIXwiyI","statistics":     {"dislikeCount":"46","likeCount":"3483","viewCount":"43745","favoriteCount":"0","commentCount":"499"}}]}

My question is how can I save this Json in an ArrayList or in a data structure, check in a Json editor online and I have an array structure in the code I try to access using a:

getJSONArray("items")

But it only returns me a position and it is blank

java json parsear arraylist rest

asked by Bryan Saltos 06.10.2018 в 00:40

source

1 answer

Find a key within a dictionary by means of a value get data from 2 tables

score 1 · Accepted Answer

I'll give you an example of how you can go through it, with this you can get the values and save them in an ArrayList for example.

public class Parser {

/**
 * @param args the command line arguments
 */
public static void main(String[] args) {

    try {
        ///Descomponer un JSON
        String respuesta="{\"items\":[{\"id\":\"Ald6YIXwiyI\",\"statistics\":     {\"dislikeCount\":\"46\",\"likeCount\":\"3483\",\"viewCount\":\"43745\",\"favoriteCount\":\"0\",\"commentCount\":\"499\"}}]}";

        JSONParser jsonParser = new JSONParser();
        JSONObject jsonObject = (JSONObject) jsonParser.parse(respuesta);

                    ///items es un Array
                    JSONArray ArrayItems= (JSONArray) jsonObject.get("items");

                    System.err.println("ARRAY:"+ArrayItems.toJSONString());

                    ///si es un array  y solo tiene una posicion,podemos acceder con la posicion 0
                    ///statistics es un objeto 
                   JSONObject statisticsFrom =(JSONObject) ArrayItems.get(0);

                    System.err.println("CUERPO:"+statisticsFrom.toJSONString());

                    ///accedemos al objecto statistics mediante su nombre por ejemplo.

                    JSONObject jsonObjectstatistics =(JSONObject) statisticsFrom.get("statistics"); 

                    System.err.println("OBJETO:"+jsonObjectstatistics.toJSONString());
                    ///con esto ya estamos dento del objecto statistics y podemos obtener todos sus campos.
                    System.err.println("dislikeCount:"+jsonObjectstatistics.get("dislikeCount"));
                    System.err.println("likeCount:"+jsonObjectstatistics.get("likeCount"));
                    System.err.println("viewCount:"+jsonObjectstatistics.get("viewCount"));
                    System.err.println("favoriteCount:"+jsonObjectstatistics.get("favoriteCount"));
                    System.err.println("commentCount:"+jsonObjectstatistics.get("commentCount"));

                    ////todo lo anterior siempre y cuando el JSON posea un solo objeto en el Array
                    ////de otra manera se puede recorrer con un for y obtener todos los valores.

                   for(int i=0; i<ArrayItems.size(); i++){

                        JSONObject cuerpo =(JSONObject) ArrayItems.get(i);
                        JSONObject statistics =(JSONObject) cuerpo.get("statistics"); 
                        ///el id lo obtenemos aqui porque esta en el objecto cuerpo
                         String id=cuerpo.get("id").toString();

                         ////Ahora recorremos finalmente el objecto statistics
                         String dislikeCount=statistics.get("dislikeCount").toString();
                         String likeCount=statistics.get("likeCount").toString();
                         String viewCount=statistics.get("viewCount").toString();
                         String favoriteCount=statistics.get("favoriteCount").toString();
                         String commentCount=statistics.get("commentCount").toString();

                        System.err.println("dislikeCount:"+dislikeCount);
                        System.err.println("likeCount:"+likeCount);
                        System.err.println("viewCount:"+viewCount);
                        System.err.println("favoriteCount:"+favoriteCount);
                        System.err.println("commentCount:"+commentCount);


                    }
    } catch (Exception ex) {
        ex.printStackTrace();
    }

 }

 }