jagakutty jagadeeshwaran jagakutty jagadeeshwaran - 2 years ago 147
JSON Question

How to fetch JSON object from Json array in REST API

I am new to REST API and handling JSON in our automation script. I have an API whose response is


[{"ProjectID":15,"ProjectName":" Securities"},{"ProjectID":16,"ProjectName":"PAS "}]

While automation, for verification I need to fetch the reponse. I have tried the below one but not getting expected output

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Scanner;
import org.json.*;

public class ProjectNameVerfication {

public static void main(String[] args) throws JSONException

URL url = new URL("http://17*.**.**.**:3000/api/******");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestProperty("Accept", "application/json");

if (conn.getResponseCode() != 200)
throw new RuntimeException("Failed : HTTP error code : " + conn.getResponseCode());

Scanner scan = new Scanner(url.openStream());
String str = new String();
while (scan.hasNext())
str += scan.nextLine();

System.out.println("str : " + str);

JSONObject obj = new JSONObject(str.substring(str.indexOf('{')));
System.out.println("obj : " +obj);
int ProjectID = obj.optInt("ProjectID");
String ProjectName = obj.getString("ProjectName");

System.out.println("ProjectID: " +ProjectID);
System.out.println("ProjectName: " +ProjectName);

JSONArray arr = obj.getJSONArray("ProjectID");
for (int i = 0; i < arr.length(); i++)
String post_id =arr.getJSONObject(i).getString("ProjectName");

catch (MalformedURLException e) { e.printStackTrace();}
catch (IOException e) { e.printStackTrace(); }


Actual output is bellow:

str : [{"ProjectID":15,"ProjectName":" Securities"},{"ProjectID":16,"ProjectName":"PAS "}]

obj : {"ProjectName":" securities""ProjectID":15}

ProjectID: 15
ProjectName: Securities

Exception in thread "main" org.json.JSONException: JSONObject["ProjectID"] is not a JSONArray.
at org.json.JSONObject.getJSONArray(JSONObject.java:539)
at MyTest.ProjectNameVerfication.main(ProjectNameVerfication.java:60)

Answer Source

Your response is an Array so you need JSONArray instead of JSONObject.

    try {

        JSONArray e = new JSONArray(str);
        int l = e.length();

        for (int x = 0; x < l; x++) {
            JSONObject object1 = e.getJSONObject(x);
            String projectID = object1.getString("ProjectID");
            String projectName = object1.getString("ProjectName");

    } catch (JSONException e) {
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