HttpURLConnection.connect() takes long time (3 minutes)

[Andy Hamilton]

I'm stumped on an unusual problem. I'm running java 1.3 and JServ (don't ask, I inherited this set up), using JSSE. One of the things we do with our app involves some xml communication over SSL.

Starting last week, the time for the SSL communication jumped from about 15 seconds to around 3 minutes.

Here is the bit of code that does the actual communication:

  
public void contactService(String service, String prefix)
  throws Exception
{
  HttpURLConnection connection;
  URL url;
  
  // the next 4 variables are stored elsewhere in the object
  // these values are just examples of one invocation
  String protocol = "https";
  String hostname = "wwwcie.ups.com";
  String prefix = "ups.app/xml";
  String service = "ShipConfirm";
  
  String urlStr = protocol + "://" + hostname + "/" + prefix + "/" + service;
  try
  {
    // Trace.log is a convenience class that will print to a log file and
    // include a timestamp
    if (protocol.equalsIgnoreCase("https"))
    {
      //use Sun's JSSE to deal with SSL
      java.security.Security.addProvider(new com.sun.net.ssl.internal.ssl.Provider());
      
      System.getProperties().put("java.protocol.handler.pkgs",
                                 "com.sun.net.ssl.internal.www.protocol");
    }
    url = new URL(urlString);
    Trace.log("open connection to " + urlString);
    connection = (HttpURLConnection) url.openConnection();
    // openConnection takes about 20 seconds now, before 1 or 2 seconds
    Trace.log("opened connection to " + urlString);
 
    // Setup HTTP POST parameters
    connection.setDoOutput(true);
    connection.setDoInput(true);
    connection.setUseCaches(false);
 
    // Get POST data from input StringBuffer containing an XML document
    // XmlIn is an already generated xml file stored in a StringBuffer
    String queryString = XmlIn.toString();
 
    Trace.log("xml connection to " + urlString);
    connection.connect();
    // connect takes about 3 minutes 10 seconds now, before 15 seconds, tops
    Trace.log("xml connection complete " + urlString);
    OutputStream out = connection.getOutputStream();
    out.write(queryString.getBytes());
    out.close();
 
    // get data from URL connection and 
    // return the XML document as a StringBuffer
    String data = "";
    try
    {
      // on the server this is actually a separate function
      StringBuffer buffer = new StringBuffer();
      BufferedReader reader = null;
      try
      {
        reader = new BufferedReader(new 
          InputStreamReader(connection.getInputStream()));
        String line = null;
        int letter = 0;
        while ((letter = reader.read()) != -1)
          buffer.append((char) letter);
      }
      catch (Exception e)
      {
        // Trace.major is like Trace.log, but is a higher severity
        Trace.major("Cannot read from URL" + e.toString());
        throw e;
      }
      finally
      {
        try
        {
          reader.close();
        }
        catch (IOException io)
        {
          Trace.major("Error closing URLReader!");
          throw io;
        }
      }
      data = buffer.toString(); // actually a return statement on server
    }
    catch (Exception e)
    {
      Trace.major("Error in reading URL Connection" + e.getMessage());
      throw e;
    }
    XmlOut = new StringBuffer(data);
  }
  catch (Exception e1)
  {
    Trace.major("Error sending data to server" + e1.toString());
  }
}
 

Besides a couple of new Trace.log statements to pin down the what's taking so long, I haven't touched this code in the year+ since I've inherited it. There haven't been any changes in the network setup for the last 3 weeks, either (new reverse lookup zone for our internal network).

Any idea why the HttpURLConnection.connect() would take so long? Or any idea how I can find out what is going on for those 3 minutes? In my search so far, I found -Djava.net.debug=ssl,handshake,data and added it to my startup parameters, but in my frustration, I must have overlooked what I need do to make it show up in my logs.

I set up a tcpdump on the server to listen on the IP that I'm trying to connect to and the "xml connection to" log statement prints, then about 3 minutes and 10 seconds goes by, then tcpdump reports that we actually send the packets to the other server, then we get a response and print the "xml connection complete" log message. URL and HttpURLConnection are not subclassed at all.

To make things even more interesting, I broke out this code, and wrote a small test program. The test program has some minor changes (pulling the xml data from an already existing file, mainly), and this version runs lickety-split (about 5 seconds).

Any help or pointers would be greatly appreciated. Let me know if I can provide any more information.

Thanks,
Andy

[Andy Hamilton]

Figured it out.

The other side removed a proxy server that we used to connect through. The server was taking 3 minutes and 10 seconds to timeout when it attempted to contact the proxy server.

To be honest, I don't know if we ever connected through the proxy server successfully. I think we may have been denied when we tried to connect. Of course, that would happen a lot faster than timing out.

Andy