[Spread-users] SpreadException: spread.SpreadException: Connection closed while reading header

[Renee Mathur]

Also attaching the excerpt of the actual fix made:


File: java\spread\SpreadConnection.java
Method: synchronized public void disconnect() throws SpreadException
Code change:


synchronized public void disconnect() throws SpreadException
	{
		// Check if we're connected.
		////////////////////////////
		if(connected == false)
		{
			throw new SpreadException("Not connected.");
		}
		
		// Are we in a listener callback?
		/////////////////////////////////
		if(callingListeners)
		{
			// Add it to the command buffer.
			////////////////////////////////
			listenerBuffer.addElement(BUFFER_DISCONNECT);
			
			// Don't need to do anything else.
			//////////////////////////////////
			return;
		}
					
		try
		{
				// Get a new message.
				/////////////////////
				SpreadMessage killMessage = new
SpreadMessage();
				
				// Send it to our private group.
				////////////////////////////////
				killMessage.addGroup(group);
				
				// Set the service type.
				////////////////////////
	
killMessage.setServiceType(SpreadMessage.KILL_MESS);
				
				// Send the message.
				////////////////////
				multicast(killMessage);
				
				// Check for a listener thread.
				///////////////////////////////
				if(listener != null)
				{
					// Stop it.
					///////////
					stopListener();
				}
				
				// Close the socket.
				////////////////////
				try
				{
					socket.close();
				}
				catch(IOException e)
				{
					throw new
SpreadException("close(): " + e);
				}
		}
		finally
		{
				connected = false;
		}
	}





Thank you.
 
Regards,
Renee Mathur.
Contractor,
Framework Support, Technology Department,
Southwest Airlines.
Ph: (W) 214.792.4644
Email: renee.mathur at wnco.com
Website: www.southwest.com

-----Original Message-----
From: Renee Mathur 
Sent: Wednesday, December 30, 2009 11:44 AM
To: 'mdistefano at integrasoftware.com'
Cc: spread-users at lists.spread.org
Subject: RE: [Spread-users] SpreadException: spread.SpreadException:
Connection closed while reading header

Hi Michael,
Sorry for the late response.
I've attached the code change I had made to make reconnection possible,
once a Spread client disconnected from the daemon.
It's a change in the disconnect method to ensure regardless of
exceptions thrown, the Boolean variable 'connected' is always reset.
I had sent the code for being encorporated in the next Spread release as
well.
Hope this helps.


Thank you.
 
Regards,
Renee Mathur.
Contractor,
Framework Support, Technology Department,
Southwest Airlines.
Ph: (W) 214.792.4644
Email: renee.mathur at wnco.com
Website: www.southwest.com

-----Original Message-----
From: Michael Di Stefano [mailto:mdistefano at integrasoftware.com] 
Sent: Monday, November 30, 2009 4:19 PM
To: Renee Mathur
Cc: spread-users at lists.spread.org
Subject: Re: [Spread-users] SpreadException: spread.SpreadException:
Connection closed while reading header

Renee

Thank you for help, your and Andrew Gilmartin's responses pointed me to 
where the exception is being thrown and not caught.   I download the 
source for 4.1 and see in the java client code

    SpreadConnection.java file Class Listener - run() method line 1637  

SpreadConnection:internalreceive() is being called but SpreadException 
is not caught.


My application layer wraps spread such that it manages load balancing 
among the spread server cluster.   The desired behavior is that if a 
server connection is lost then attempt a reconnect to another server in 
the cluster.   Given the above, I see no way to get control back to my 
code to manage reconnects.   I guess my only option is to simply exit().

This brings me to my next "feature".  When I detect a closed connection 
on a send, I can not reconnect to any server, the message is that I am 
already connected.  This sounds like boolean variable check you describe

below.

If you can please send me that code I would appreciate it.

Regards

Michael




Renee Mathur wrote:
> There is a bug in the client side piece of Spread-4.0.jar where it
does not clear the state of a boolean variable if the spread daemon
dies. Reconnection logic just checks for the boolean variable and if
its' true, it assumed it's already connected, and does not attempt a
re-connection.
> I'd sent an email about this to the spread group about 2-3 months back
along with a fix to the source code.
> Let me know if you can't find it. I should be able to dig it for you -
but only after I get back from my vacation in late Dec.
> Regards,
> Renee.
>  
>
> ________________________________
>
> From: spread-users-bounces at lists.spread.org on behalf of Michael Di
Stefano
> Sent: Sat 11/28/2009 12:51 PM
> To: spread-users at lists.spread.org
> Subject: [Spread-users] SpreadException: spread.SpreadException:
Connection closed while reading header
>
>
>
> Hi
>
> I am testing my application for error conditions and purposefully
> killing the spread server.  There is no message activity, the
> application is just sitting listening for a message.   (I am using a
> Basic Message Listener)
>
> When I kill the server I get
>   
>      SpreadException: spread.SpreadException: Connection closed while
> reading header
>
> printed to standard out.   I do not seem to be able to find where this
> exception is being thrown/printed and where to catch the exception so
I
> can exit my program.
>
> My environment is
>
>    --- spread server is running on a MAC
>    --- Application is a written in Java using spread-4.0.0.jar
>
> Any advise is appreciated.
>
> Thanks
>
> Michael
>
>
>
>
>
>
>                                                                    
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