android - HttpUrlConnection.openConnection fails second time

Question

I know this issue should be fixed with System.setProperty("http.keepAlive", "false"); before openConnection, but that didn't work to me. First try on this code works, second one fails. Even if i try this request after less than 5 seconds, it also works. If i wait more than that, it fails again

This is my code:

    System.setProperty("http.keepAlive", "false");
  HttpURLConnection conn = (HttpURLConnection) mURL.openConnection();
  conn.setUseCaches(false); 
  conn.setRequestProperty("Connection","Keep-Alive"); 
  conn.setRequestProperty("User-Agent", useragent);
  conn.setConnectTimeout (30000) ; 
  conn.setDoOutput(true); 
        conn.setDoInput(true); 

  consumer.sign(conn);
  InputSource is = new InputSource(conn.getInputStream());

I get the exception on last line:

java.io.IOException: Write error: I/O error during system call, Broken pipe
W/System.err( 2164):  at org.apache.harmony.xnet.provider.jsse.OpenSSLSocketImpl.nativewrite(Native Method)
W/System.err( 2164):  at org.apache.harmony.xnet.provider.jsse.OpenSSLSocketImpl.access$600(OpenSSLSocketImpl.java:55)
W/System.err( 2164):  at org.apache.harmony.xnet.provider.jsse.OpenSSLSocketImpl$SSLOutputStream.write(OpenSSLSocketImpl.java:583)
W/System.err( 2164):  at java.io.OutputStream.write(OutputStream.java:82)
W/System.err( 2164):  at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.sendRequest(HttpURLConnectionImpl.java:1332)
W/System.err( 2164):  at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.doRequestInternal(HttpURLConnectionImpl.java:1656)
W/System.err( 2164):  at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.doRequest(HttpURLConnectionImpl.java:1649)
W/System.err( 2164):  at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:1153)
W/System.err( 2164):  at org.apache.harmony.luni.internal.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:253)

Does someone have an idea about what's wrong here?. Thanks!

Answer 1

The connection pool used by HttpURLConnection when it is keeping connections alive is broken such that it tries to use connections that have been closed by the server. By default Android sets KeepAlive on all connections.

System.setProperty("http.keepAlive", "false"); is a workaround that disables KeepAlive for all connections so then you avoid the bug in the connection pool.

conn.setRequestProperty("Connection","Keep-Alive"); turns KeepAlive on for this particular connection, essentially reversing what System.setProperty("http.keepAlive", "false"); does.

Also I always explicitly call connect() as it makes it clear where you are ending your connection setup. I'm not sure if calling this method is optional or not.

System.setProperty("http.keepAlive", "false");
HttpURLConnection conn = (HttpURLConnection) mURL.openConnection();
conn.setUseCaches(false); 
conn.setRequestProperty("User-Agent", useragent);
conn.setConnectTimeout(30000);
conn.setDoOutput(true); 
conn.setDoInput(true); 
consumer.sign(conn);

conn.connect();

InputSource is = new InputSource(conn.getInputStream());