javaandroidandroid-json

Android - Get Data using InputStream returning nothing/empty


I am parsing data of JSON that starts something like this below...

[
   {"title":"dummy", "content":"ajsfhk"},
   {"title":"dummy", "content":"ajsfhk"},
   {"title":"dummy", "content":"ajsfhk"},
]

And my android async task class is below. But it shows that "NegativeArraySizeException"

class RetrieveFeedTask extends AsyncTask<Object, Void, String> {

    @Override
    protected String doInBackground(Object... arg0) {
        int responseCode = -1;
        try {
            URL retailerUrl = new URL("https://clients.appatlantis.com/soldy/wp-json/wp/v2/soldy-clients?_embed");
            HttpsURLConnection connection = (HttpsURLConnection) retailerUrl.openConnection();
            connection.connect();

            responseCode = connection.getResponseCode();

            if (responseCode == HttpsURLConnection.HTTP_OK) {
                InputStream inputStream = connection.getInputStream();
                Reader reader = new InputStreamReader(inputStream);
                int contentLength = connection.getContentLength();
                char[] charArray = new char[contentLength];
                reader.read(charArray);
                String responseData = new String(charArray);
                Log.e(TAG, "Parse Data "+responseData);
            } else {
                Log.e(TAG, "Parse Data Failed");
            }

        } catch (MalformedURLException e) {
            Log.e(TAG, "URL Exeption: ", e);
        } catch (IOException e) {
            Log.e(TAG, "IO URL Exeption: ", e);
        } catch (Exception e) {
            Log.e(TAG, "Exeption Caught: ", e);
        }

        return "Response Code "+responseCode;
    }
}

And here is the exception trace

2020-04-10 15:12:31.322 27385-27449/com.appatlantis.soldy E/MainActivity: Exeption Caught: 
    java.lang.NegativeArraySizeException: -1
        at com.appatlantis.soldy.MainActivity$RetrieveFeedTask.doInBackground(MainActivity.java:149)
        at com.appatlantis.soldy.MainActivity$RetrieveFeedTask.doInBackground(MainActivity.java:132)
        at android.os.AsyncTask$2.call(AsyncTask.java:333)
        at java.util.concurrent.FutureTask.run(FutureTask.java:266)
        at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:245)
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
        at java.lang.Thread.run(Thread.java:764)

I don't understand much about JSON.


Solution

  • contentLength is -1. Note the error:

        java.lang.NegativeArraySizeException: -1
            at com.appatlantis.soldy.MainActivity$RetrieveFeedTask.doInBackground(MainActivity.java:149)
    

    This tells you that you tried to initialize an array with a size of -1 on line 149, which I'm assuming based on the crash is

    char[] charArray = new char[contentLength];
    

    From the docs for getContentLength(), this means that the content length isn't known. You should look into parsing the JSON directly from an InputStream - it'll save you the trouble of trying to do this yourself.