In the JSON Response String contains auto-added Backslashes

Question

I am calling a webservice to get a JSON string response and It contains backslashes which is not in original string. Below is my code for requesting a JSON string object which is: {"name":"Name","id":1}

protected String doInBackground(String... uri) 
    {
        HttpClient httpclient = new DefaultHttpClient();
        HttpResponse response;
        String responseString = null;
        try {
            response = httpclient.execute(new HttpGet(uri[0]));
            StatusLine statusLine = response.getStatusLine();
            if(statusLine.getStatusCode() == HttpStatus.SC_OK){
                ByteArrayOutputStream out = new ByteArrayOutputStream();
                response.getEntity().writeTo(out);
                out.close();
                responseString = out.toString();
            } else{
                //Closes the connection.
                response.getEntity().getContent().close();
                throw new IOException(statusLine.getReasonPhrase());
            }
        } catch (ClientProtocolException e) {
            //TODO Handle problems..
        } catch (IOException e) {
            //TODO Handle problems..
        }
        return responseString;
    }

In post execute I just try to parse this respose string into JSONObject. code is bellow:

protected void onPostExecute(String result) {
        super.onPostExecute(result);
        TextView t1=(TextView)findViewById(R.id.textView1);
        TextView t2=(TextView)findViewById(R.id.textView2);       

        //String s = result.replaceAll("\\", ""); //I have tried to escape backslashes also using this line.
        String name="failure";
        int id;
        try 
        {
            t1.setText(result);
            JSONObject reader = new JSONObject(result.toString()); //Exception on this line.
            //name = reader.getString("name").toString();
            //id = reader.getInt("id");             
            t2.setText(name);
        } 
        catch (Exception e) 
        {
            t2.setText(e.toString());
        }
    }

Rsponse string is: "{\"name\":\"Name\",\"id\":1}" And when I try to parse it to JSONObject it throws an exception says: org.json.JSONException value "{"name":"Name","id":1}" type cannot converted into json object.

Margo

not sure what is problem, however , backslash does't seem problem. Backslash is just escape characeter. Even in exception string is correctone – Gettings

I printed out the information and it prints backslashes...if these are here as escaped characters then it should not be printed?right – Margo

Answer 1

I know this is an old question, but I got stuck with the same problem , the only difference that, I had a JSONArray instead of a JSONObject . But the method I followed for my problem after scouring Stackoverflow for similar questions was the one I am going to state below, in case anyone comes looking for an answer just as I stumbled across your question.

First of all,you need to study the json response you receive. "{\"name\":\"Name\",\"id\":1}" is a String. You see the " before { and after }. If this string is the raw json you receive from your web service,then your method to escape the backslashes and then building a JSONObject out of that string ought to have worked. One method you could try is :

result = result.trim();
result = result.substring(1,result.length() - 1);
result = result.replace("\\","");

Then,

JSONObject reader = new JSONObject(result);
name = reader.getString("name");
id = reader.getInt("id"); 

The mantra for this solution was to get rid of those extra inverted commas before the json response and then creating a JSONObject from that string.

As for my situation regarding a JSONArray,the solution was as below:

Json response : {"error":false,"myorderdetails":{"order_id":"26","orderjson":"[{\"Name\":\"Disprin\",\"Id\":53,\"Quantity\":1,\"Price\":50}]"}}

JSONObject jObj = new JSONObject(response);
boolean error = jObj.getBoolean("error");
if (!error)
{
    JSONObject jsonObj= jObj.getJSONObject("myorderdetails");
    String s = jsonObj.getString("orderjson");
    s = s.replace("\\", "");
    JSONArray orderjson = new JSONArray(s);

    for(int i=0;i<orderjson.length();i++){
    JSONObject jsonObject=orderjson.getJSONObject(i);
    String pname = (String)jsonObject.get("Name");
    int pquantity = jsonObject.getInt("Quantity");
    double pprice = jsonObject.getDouble("Price");
}

Patter

Answer 2

Adding this header in request solved my problem :

"Content-Type" = "application/x-www-form-urlencoded"

Jodee

Answer 3

Look at your list message converters. It looks like your Json converter (MappingJackson2HttpMessageConverter for example) resides before StringMessageConverter. And json adding escape character '\' before '"' to every string it converts.

Execution