Develop Reference

How to force HttpURLConnection request to wait for full response?

I am trying to get a JSON response using this code.
it works fine for short responses (20 to 30 lines) but cuts off in middle of longer ones.
final HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
if (connection.getResponseCode() != 200) { throw new Exception(); }
BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String inline; StringBuilder response = new StringBuilder();
while ((inline = in.readLine()) != null) {
response.append(inline);
}
in.close();
Log.d(TAG, "getJson: {"+url.toString()+"}\n"+response.toString());
return response.toString();
Sample of the logcat output showing cutoff json here.
How can I force it to always download the full response?
Edit:
It seems from the comments that this question generated, as well as further testing, that there is nothing inherent or lacking in the code that is causing the server to truncate, but that this is an android specific problem.
Can anyone, A) identify why long responses (use example link above) truncate specifically on android (whether from above code, or in android browser), and B) - (the real question) is there a way to programatically overcome the issue?

Upload file on server using Rest API

I want to commit text file "demo2.txt" to bitbucket server using rest API. I can upload the same file using Postman but it's not working with Java code. As shown in the below code I want to send string object "str" as the body. Can someone help me here to upload the file on the bitbucket server? Also Please let me know if there is any other way to do this.
URL url = new URL("https://api.bitbucket.org/2.0/repositories/{team name}/{repository name}/src");
HttpURLConnection httpCon = (HttpURLConnection) url.openConnection();
httpCon.setRequestProperty("X-Requested-with", "Curl");
httpCon.setDoOutput(true);
httpCon.setDoInput(true);
httpCon.setRequestProperty("Connection", "Keep-Alive");
httpCon.setRequestProperty("Content-Type", "multipart/form-data; boundary="+boundary);
httpCon.setRequestProperty("Accept", "application/x-www-form-urlencoded");
httpCon.setRequestProperty("Authorization", basicauth);
httpCon.setRequestMethod("POST");
String str =
"{"
+ "\"-F\":\"File3=#/D:/log/demo2.txt\" "
+ "}";
try {
OutputStream output = httpCon.getOutputStream();
output.write(str.getBytes());
output.close();
} catch(Exception e){
System.out.println(e.getMessage());
}
int responseCode = httpCon.getResponseCode();
String inputLine;
StringBuffer response = new StringBuffer();
if (responseCode == HttpURLConnection.HTTP_OK || responseCode == HttpURLConnection.HTTP_CREATED){
BufferedReader in = new BufferedReader(new .
InputStreamReader(httpCon.getInputStream()));
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
List<String> message = new ArrayList<>();
message.add(response.toString());
}

If this is all of your code, then your problem may be as simple as the fact that you're not making any sort of call to finalize the request...to tell HttpURLConnection that you're done forming the request and want it to complete. There are two things you can do to help this:
close the output stream when you're done writing to it. You're generally supposed to do this. Here, you can call output.close(). Better still, since you have a try/catch block already anyway, use a "try with resources" construct to make sure that the stream is closed no matter what happens (assuming you're using a newer version of Java that supports this).
make some sort of call to query the response to the request. It may
be that the request is not being fully sent until you do this. Try
calling httpCon.getResponseCode() at the bottom of your code.
Given that you have provided no information as to what "it's not working with Java code" means, this may be useful information but not the ultimate solution to your problem. Your code does look good other than exhibiting these omissions.

Posting minutiae byte array from applet to server

In Grails web application, I am trying to post minutiae (finger print) byte array from applet to server using rest API.
This what i tried so for
private String post(String purl,String customerId, byte[] regMin1,byte[] regMin2) throws Exception {
StringBuilder parameters = new StringBuilder();
parameters.append("customerId=");
parameters.append(customerId);
parameters.append("&regMin1=");
parameters.append(URLEncoder.encode(new String(regMin1),"UTF-8"));
parameters.append("&regMin2=");
parameters.append(URLEncoder.encode(new String(regMin2),"UTF-8"));
URL url = new URL(purl);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoOutput(true);
connection.setDoInput(true);
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
connection.setRequestProperty("Content-Length",Integer.toString(parameters.toString().getBytes().length));
DataOutputStream wr = new DataOutputStream(connection.getOutputStream ());
wr.writeBytes(parameters.toString());
wr.flush();
wr.close();
BufferedReader in = new BufferedReader(new InputStreamReader(
connection.getInputStream()));
StringBuilder builder = new StringBuilder();
String aux = "";
while ((aux = in.readLine()) != null) {
builder.append(aux);
}
in.close();
connection.disconnect();
return builder.toString();
}
I can post regMin1, regMin2 successfully but fingerprint verification always failing. I doubt, am i posting correctly.

This looks like a very bad idea to me:
parameters.append(URLEncoder.encode(new String(regMin1),"UTF-8"));
...
parameters.append(URLEncoder.encode(new String(regMin2),"UTF-8"));
If regMin1 and regMin2 aren't actually UTF-8 text (and my guess is that they're not) you'll almost certainly be losing data here.
Don't treat arbitrary binary data as if it's encoded text.
Instead, convert regMin1 and regMin2 to base64 - that way you'll end up with ASCII characters which you can then decode on the server to definitely get the original binary data. You can use a URL-safe version of base64 to avoid having to worry about further encoding the result.
There's a good public domain base64 library you can use for this if you don't have anything else to hand. So for example:
parameters.append("&regMin1=")
.append(Base64.encodeBytes(regMin1, Base64.URL_SAFE))
.append("&regMin2=")
.append(Base64.encodeBytes(regMin2, Base64.URL_SAFE));
Note that you'd want to decode with the URL_SAFE option as well - don't just try to decode it as "normal" base64 data.
(You might still want to convert this to a POST request, and you'd definitely have an easier time if you could use a better HTTP library, but they're slightly separate concerns.)

getContentLength returning 1225, real length 3365

I am currently working with android and i am using a http connection with some headers (i havent included them or the real url for security purposes) to get a JSON response from an API, and feeding that response back into the application. The problem that i am having is that when using the getContentLength method of the http request, the wrong length is being returned (wrong length returned is 1225, the correct length in characters of the JSON array is 3365).
I have a feeling that the JSON is not fully loaded when my reader starts to read it, and as such is only reading the loaded JSON at that point. Is there any way around this, possibly using a delay on the HTTP connection or waiting until it is fully loaded to read the data?
URL url = new URL("https://www.exampleofurl.com");
HttpURLConnection request = (HttpURLConnection) url.openConnection();
request.connect();
int responseCode = request.getResponseCode();
if(responseCode == HttpURLConnection.HTTP_OK) {
InputStream inputStream = request.getInputStream();
InputStreamReader reader = new InputStreamReader(inputStream);
long contentLength2 = Long.parseLong(request.getHeaderField("Content-Length"));
Log.i("contentLength: ", "Content: " + contentLength2);

I generally don't recommend always relying on "Content-Length" as it may not be available (you get -1), or perhaps affected by intermediate proxy.
Why don't you just read your stream until it is exhausted into memory buffer (say, StringBuilder) and then get the actual size, for example :
BufferedReader br = new BufferedReader(inputStream); // inputStream in your code
String line;
StringBuilder sb = new StringBuilder();
while ((line = br.readLine()) != null) {
sb.append(line);
}
// finished reading
System.out.println("data size = " + sb.length());
JSONObject data = new JSONObject(sb.toString());
// and don't forget finally clauses with closing streams/connections

HttpURLConnection getInputStream() has one second delay

I am using HttpURLConnection for making POST requests. I observe always the same behaviour during tests:
first request runs very fast (miliseconds)
all following requests take one second + some miliseconds
So something is causing 1 second delay. What can it be? The delay is happening exactly in HttpURLConnection#getInputStream().
I replaced the implementation with HttpClient - then everything is OK, no second delays (so it is not the server fault). But I really don't want to use any external dependency, so I would like to fix the HttpURLConnection thing... Any ideas?
Below current implementation. I tried some tips from stackoverflow (adding headers to the request), but with no success.
URL obj = new URL(url);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
con.setRequestMethod("POST");
con.setRequestProperty("Content-Length", ""
+ (body == null ? 0 : body.length));
// Send post request
con.setDoOutput(true);
OutputStream wr = con.getOutputStream();
if (body != null) {
wr.write(body);
}
wr.flush();
wr.close();
BufferedReader rd = new BufferedReader(new InputStreamReader(
con.getInputStream()));
String line;
String result = "";
while ((line = rd.readLine()) != null) {
result += line;
}
rd.close();
con.disconnect();
return result;
PS: It is about jse, not android.

You're never closing the input stream from the connection - that may mean that the connection isn't eligible for pooling, and on the next attempt it's waiting for up to a second to see if the previous request's connection will become eligible for pooling.
At the very least, it would be a good idea to close the stream. Use a try-with-resources block if you're using Java 7 - and ditto for the writer.
As an aside, I suggest you explicitly state the encoding you expect when reading - or use a higher-level library which detects that automatically based on headers.