Android application doesn't read entire HTTP response

Question

I have written a web-service in Java. This web-service is hosted in TOMCAT. I am returning a JSON string. The JSON string is as follows:

accountDetailsNodes = [{mobileNumber=01948330292, errorMessage=null, customerCode=59744000002, photo=a string of 35536 charaters , accountOpenDate=null, errorFlag=N, customerNumber=4, customerName=Md. Saifur Hossain , accountID=2, accountTypeId=13, accountTypeDescription=Savings Account, customerPointId=1, balance=100000037640.50, accountTile=Md. Saifur Hossain}]

The length of the JSON string is 32613. But the full response is not coming to android apps. I think there may be some limitation on sending response from Tomcat. How can I overcome this limitation of Tomcat?

Updated:

This is my code to generate JSON.

try {
            List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
            JSONObject json = new JSONObject();
            CashDepositDao dao = new CashDepositDao();
            for (CashDepositModel bo : dao.getAccountDetals(accountNo,branchCode)) {
                Map<String, Object> map = new HashMap<String, Object>();
                map.put("accountTile", bo.getAccountTitle());
                map.put("accountOpenDate", bo.getAccountOpenDate());
                map.put("mobileNumber", bo.getMobileNumber());
                map.put("balance", bo.getBalance());
                map.put("accountTypeId", bo.getAccountTypeID());
                map.put("accountTypeDescription", bo.getAccountTypeDescription());
                map.put("accountID", bo.getAccountID());
                map.put("customerNumber", bo.getCustomerNumber());
                map.put("customerCode", bo.getCustomerCode());
                map.put("customerName", bo.getCustomerName());
                map.put("customerPointId", bo.getCustomerPointID());
                map.put("photo", bo.getPhoto());
                map.put("errorMessage", bo.getErrorMessage());
                map.put("errorFlag", bo.getErrorFlage());

                list.add(map);
                json.put("accountDetailsNodes", list);

            }
            System.out.println("accountDetailsNodes = " + list);
            response.addHeader("Access-Control-Allow-Origin", "*");
            response.setContentType("application/json");
            response.setCharacterEncoding("UTF-8");
            response.getWriter().print(json.toString());
            response.getWriter().flush();
            // System.out.println("Response Completed... ");
        } catch (Exception ex) {
            Logger.getLogger(SourecAccountDetailsSV.class.getName()).log(Level.SEVERE, null, ex);
        }

Sending And Getting response from Mobile App:

I am sending and getting the response using the following code:

public JSONObject makeHttpRequest(String url, String method,
            List<NameValuePair> params) {

        // Making HTTP request
        try {

            // check for request method
            if(method == "POST"){
                // request method is POST
                // defaultHttpClient
                DefaultHttpClient httpClient = new DefaultHttpClient();
                HttpPost httpPost = new HttpPost(url);
                httpPost.setEntity(new UrlEncodedFormEntity(params)); 
                HttpResponse httpResponse = httpClient.execute(httpPost);
                HttpEntity httpEntity = httpResponse.getEntity();
                is = httpEntity.getContent();

            }else if(method == "GET"){
                // request method is GET
                DefaultHttpClient httpClient = new DefaultHttpClient();
                String paramString = URLEncodedUtils.format(params, "utf-8");
                url += "?" + paramString;
                HttpGet httpGet = new HttpGet(url); 
                HttpResponse httpResponse = httpClient.execute(httpGet);
                HttpEntity httpEntity = httpResponse.getEntity();
                is = httpEntity.getContent();
            }          

        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    is, "iso-8859-1"), 8);
            StringBuilder sb = new StringBuilder();
            String line = null;
            while ((line = reader.readLine()) != null) {
                sb.append(line + "\n");
            }
            is.close();
            json = sb.toString();
            System.out.println(json);
        } catch (Exception e) {
            Log.e("Buffer Error", "Error converting result " + e.toString());
        }

        // try parse the string to a JSON object
        try {
            jObj = new JSONObject(json);
        } catch (JSONException e) {
            Log.e("JSON Parser", "Error parsing data " + e.toString());
        }

        // return JSON String
        return jObj;

    }

I have printed the string received in this method . Surprisingly, the full string is not received in this method.

And I think there may be some error in the code you didn't show. — blafasel, Sep 06 '17 at 11:40
The question is updated . I have checked the json string in webservice . The full string is shown while in android app, the full string is not shown . — Christopher Marlowe, Sep 06 '17 at 11:45
What do you mean by "in android app, the full string is not shown"? — f1sh, Sep 06 '17 at 11:47
Have you tested your web service using Postman or something similar? Do you get a full response there? — Andrew Stalker, Sep 06 '17 at 11:48
Browser can show the full length json string . But the app cannot get the full json string . — Christopher Marlowe, Sep 06 '17 at 12:01
**What** app? Evidence required. Mere repetition is not sufficient. Code please. London to a brick your read loop is wrong, assuming you even have one. The fact that he browser shows it correctly *completely exonerates* both your servlet and Tomcat. The error is in your Android app. Accept it. Post it, or at least the relevant parts. In your question. — user207421, Sep 06 '17 at 12:02
Duplicate of [How do I compare strings in Java?](https://stackoverflow.com/questions/513832/how-do-i-compare-strings-in-java) — user207421, Sep 06 '17 at 12:33
What is the relation between comparing string and my questions ? Surprised . — Christopher Marlowe, Sep 06 '17 at 12:34
Have a look at the answers, and compare them to how you are comparing strings in your code. You also have a scoping error with `is`, which should be a local variable. — user207421, Sep 06 '17 at 12:35

Olaf Kock · Answer 1 · 2017-09-06T13:39:06.437

How can I overcome this limitation of tomcat ?

Tomcat can send arbitrary length strings, and even if there was a limit, it wouldn't be measured in kilobytes but in orders of magnitude more. There is no tomcat limitation that you need to overcome. If your browser receives the full string, so can any other app.

As you're using json.toString() anyways, you could explicitly set the Content-Length header and see if this makes a difference. Stop worrying about Tomcat and double check if your Android App has some problems parsing a json response of this size, or if any network component in between limits your response in some way.

Edit: It's not Tomcat's problem, it's on the Android side and your answer is in the comments to the question.

The first problem is in what's proposed as "duplicate" question: You must not compare String with == as you do. Add else System.out.print("unexpected"); to your first if/else block to illustrate.

The second problem is that we have no clue where you get is from. As it looks now, it could be overridden by parallel requests (it's probably a class member?) - or due to the wrong string comparison never be initialized at all (leading to your problem that you can't see any content at all on the Android side, despite tomcat sending it). Make it a local variable, as proposed by EJP in his/her comment.

The servlet container sets `Content-length` automatically. Setting it yourself won't make any difference. It will get overridden by the container. — user207421, Sep 06 '17 at 12:12

score 0 · Answer 2 · answered Sep 07 '17 at 01:44

I think there may be some limitation on sending response from Tomcat.

There isn't.

How can I overcome this limitation of Tomcat?

There is no such limitation.

I am sending and getting the response using the following code:

public JSONObject makeHttpRequest(String url, String method,
            List<NameValuePair> params) {

        // Making HTTP request
        try {

            // check for request method
            if(method == "POST"){

Here you are incorrectly comparing strings. You should use equals(), not ==.

                // ...
            }else if(method == "GET"){

Ditto.

        try {
            BufferedReader reader = new BufferedReader(new InputStreamReader(
                    is, "iso-8859-1"), 8);

Here you are using is which may not have been initialized at all. It appears to be a member variable, so it is probably still null, so at this point I would expect a NullPointerException. is should of course be a local variable in this method.

I have printed the string received in this method. Surprisingly, the full string is not received in this method.

What is surprising is that anything is received, if that's what you're claiming. I would have expected an NPE.

The string is partially received . Total character of json string from web-service is 32613 . But in android app , only 4567 characters are received . — Christopher Marlowe, Sep 07 '17 at 04:38

Android application doesn't read entire HTTP response

2 Answers2