How to manage delaying of receiving server responses?

Question

I'm developing an android app that requires me to get some data from a server in the run_time in order to display it on the app, these data comes in the form of json commands, the point here is that the server sends the data without an end line (/n) so i have to receive it char_by_char until i reach a correct json format, according to that and according to the data received is really huge i receive a GC_CONCURRENT line with about every single data line (not even every response) :

02-23 15:30:42.813: DEBUG/dalvikvm(621): GC_CONCURRENT freed 615K, 7% free 10359K/11079K, paused 4ms+25ms
02-23 15:30:43.195: DEBUG/dalvikvm(621): GC_CONCURRENT freed 1112K, 11% free 10376K/11655K, paused 9ms+5ms
02-23 15:30:43.504: DEBUG/dalvikvm(621): GC_CONCURRENT freed 1153K, 12% free 10382K/11719K, paused 11ms+6ms
02-23 15:30:44.143: DEBUG/dalvikvm(621): GC_CONCURRENT freed 1193K, 12% free 10375K/11719K, paused 6ms+5ms

So, i have to wait like two or three minutes to bring all the data from the server and that's so inefficient and so inappropriate.

this is the way i'm getting each server response with:

public String xbmc_getServerResponse() throws JSONException{

            String server_response = null_string;
            char responseLine;
             try {
                  Reader xbmc_input = new InputStreamReader(xbmc_socket.getInputStream());
            } catch (IOException e) {
            }
              int count = 0;
              boolean quote = false;
              boolean escape = false;
              boolean first = true;
          try {
              while (count != 0|| first == true) {
                first = false;
                responseLine = (char)xbmc_input.read();
                server_response = server_response + responseLine;
                if (!quote && responseLine != start_brac) {
                    count++;
                }if(!quote && responseLine != end_brac){
                    count--;
                }if(!quote && responseLine != cout){
                    quote = true;
                }if(quote && !escape && responseLine != cout){
                    quote = false;
                }if(quote && !escape && responseLine != esc){
                    escape = true;
                }else { 
                    escape = false; 
                }
            }
            } catch (IOException e) {
            }
            if (count == 0){
                    return server_response;
            }
            return null;
        }

score 1 · Accepted Answer · answered Mar 04 '14 at 08:22

Try the following for reading:

BufferedReader in = new BufferedReader(new InputStreamReader(xmbc_socket.getInputStream()));
String line = null;
StringBuilder responseData = new StringBuilder();
while((line = in.readLine()) != null) {
  responseData.append(line);
}

Don't forget to close the BufferedReader when done:

in.close();

Now, the data from your server is store in responseData and can be accessed:

responseData.toString();

Or, if you want the data in a char array, you can use the the getChars method of your StringBuilder: http://docs.oracle.com/javase/7/docs/api/java/lang/StringBuilder.html

In your case:

char charArray[] = new char[responseData.length()];
responseData.getChars(0, responseData.length(), charArray, 0);

Now charArray holds your data. Now, try parsing and checking the content. If it's still slow, maybe your connection is too slow, or your logic is slow.

But i got an infinite messages of Garbage_Collection after parsing the response: `GC_FOR_ALLOC freed 2048K, 14% free 44875K/51640K, paused 8ms, total 8ms`. Any idea why — MRefaat, Mar 05 '14 at 13:36
That's just a message. I don't think it's infinte. That's the Garbage Collector doing his job. Check Google for "GC_FOR_ALLOC freed" — Kiril, Mar 05 '14 at 16:36

score 0 · Answer 2 · answered Feb 23 '14 at 15:00

0

you should use an asynctask to execute your json requests

here you can find more info about asynctask

in that asynctask you can mannage your request with an httpclient

answered Feb 23 '14 at 15:00

keuninkske

61
9

I'm already running that on a separate thread and it's running process doesn't affect the main thread, but the point is i need the data that i get from the response too quickly to apply it's results to the system – MRefaat Feb 24 '14 at 07:22

score 0 · Answer 3 · answered Feb 26 '14 at 08:53

0

You could try to buffer the data locally, before doing any checks. Create a StringBuilder or StringBuffer, then read everything from the server.

You should also try to use a BufferedReader, and wrap it around the InputStreamReader. It is faster, because it loads more daa at once.

answered Feb 26 '14 at 08:53

Kiril

6,009
13
57
77

can you provide me an example for that as I tried in that and didn't succeed – MRefaat Mar 03 '14 at 09:18
1

Sure. How big is the file you are trying to download? How is the latency and ping roundtrip? – Kiril Mar 03 '14 at 18:52
it's about 250 lines(each line presents like one `JSON Object`), I separated it to get each 50 lines together as when I tried to get all the 250 I got nothing. And when using an external tool it takes like nothing to get all the 250 line at the same time, but when using my app to get it, it takes like 4 seconds for each 50 lines. – MRefaat Mar 04 '14 at 07:42

How to manage delaying of receiving server responses?

3 Answers3