android - Get error in retrieve pdf file from firebase database

Question

I am trying to retrieve it from firebase

 pdfView= findViewById(R.id.pdfView);
    url= String.valueOf(DbQuery.g_paperList.get(DbQuery.g_selected_paper_index).getPaperURL());
}
class RetrievePDFbyte extends AsyncTask<String,Void,byte[]>{
   
    @Override
    protected byte [] doInBackground(String... strings) {
        InputStream inputStream = null;
        try{
            URL url=new URL(strings[0]);
            HttpsURLConnection httpsURLConnection=(HttpsURLConnection)url.openConnection();
            if (httpsURLConnection.getResponseCode()==200){
                inputStream=new BufferedInputStream(httpsURLConnection.getInputStream());
            }
        }catch (IOException e){
            return null;
        }
        try {
            return IOUtils.toByteArray(inputStream);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return  null;
    }

    @Override
    protected void onPostExecute(byte[] bytes) {
        pdfView.fromBytes(bytes).load();
        progress_Dialog.dismiss();
    }

}

but I am not able to use AsyncTask ,doInBackground and onPostExecute. How i acn retrieve it from the firebase database

error i am getting

question from:https://stackoverflow.com/questions/65920661/get-error-in-retrieve-pdf-file-from-firebase-database

Answer 1

Waitting for answers