Android HttpURLConnection content length

Question

I am trying to download files from a server in android and show progress dialog using code very similar to the answer provided in this thread but i am not able to get content length in HttpURLConnection's getContentLength() method. Content length for all files is -1.

For the same file, i get correct content length in iOS app with NSHTTPURLResponse's expectedContentLength method.

Is there some basic difference in the way these methods fetch the content length for an http connection/response?

EDIT 1:

Tried following few things as suggested some answers and comments.

Set Accept-Encoding header to identity
Fetching the content length as string (from header field Content-Length) and then converting it to long
Tried conn.getContent().toString().length() instead of getContentLength()

None of these worked for me yet.

What baffles me most is i get the content length in iOS but not on android.

EDIT 2:

Heres my iOS and Android code for comparison -

iOS:

NSURLRequest *request = [NSURLRequest requestWithURL:self.url cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:1200.0];
NSURLConnection *connection = [[NSURLConnection alloc] initWithRequest:request delegate:self startImmediately:NO];
[connection scheduleInRunLoop:[NSRunLoop currentRunLoop] forMode:NSDefaultRunLoopMode];
[connection start];

Android:

URL url = new URL(downloadUrlString);
connection = (HttpURLConnection) url.openConnection();
connection .setRequestProperty("Accept-Encoding", "identity");
connection.connect();

The only difference i can see is caching. So i added following line in android code as well but nothing changed.

connection.setUseCaches(true);

@R4j i checked the link. I tried it but it did not work. Answer in that link is more valid for httprequests which return the correct content length but are too large for an int. I am not getting any content-lentgth. — Swapnil Luktuke, Mar 04 '14 at 09:16
Depending on the webserver, the protocol, the connection, or the method of downloading, `Content-length` may not always be available. But for your case, I think you should make a request like ios does (check your header, content type...). Or maybe you should provide your ios code then people can help you. — ductran, Mar 04 '14 at 09:28

score 3 · Answer 1 · answered Mar 04 '14 at 08:36

3

try this:

   HttpURLConnection conn = (HttpURLConnection)url.openConnection();
   conn .setRequestProperty("Accept-Encoding", "identity");
   conn.connect();

answered Mar 04 '14 at 08:36

MengMeng

1,016
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1

Worked for me!!! In my case it was an issue with the server update, when server didn't send content-length header when encoding was gzip. – deko Mar 04 '15 at 14:57

score 0 · Answer 2 · answered Mar 04 '14 at 08:47

0

if you just need to content length, can you try

  conn.getContent().toString().length()

where conn is the HttpURLConnection object

answered Mar 04 '14 at 08:47

Mina Tadros

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6
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I get -1 as the content length with this approach as well. – Swapnil Luktuke Mar 04 '14 at 09:11
this means there is no content length, I think your problem not in the content length. It is the way of connect. As you mentioned, you got the file by ISO and you read content. This means you forget to set something in the header before making connect or you set something wrong. – Mina Tadros Mar 04 '14 at 10:05

score 0 · Accepted Answer · edited May 23 '17 at 12:20

Root cause for this problem turned out to be Cookies.

I am using a web view in one of the activities in my application. Some cookies are stored by the web view. All other REST api and file download requests work without those cookies however for a particular type of requests, the cookies are necessary.

Apparently, android web view and the connection requests do not share cookies out of the box like iOS. As a result i had to make changes in my code to make sure that the HttpUrlConnection uses WebKit's cookie store. I did it using method described in the accepted answer for this question.

Android HttpURLConnection content length

3 Answers3