I've been playing around with my Java client app. Behaviour is very similar to this post (and others):
java.net.SocketException: Software caused connection abort: recv failed
As yet I've not found the answer - hence this post. I have a idea what is wrong but I'm not sure what to do about it.
The protocol is simple - read some data in, send back an ACK and repeat (until terminted).
I've been looking at what is going on with WireShark, and is seems the TCP window is filling up. I'm performing a flush() on the DataOutputStream (For the ACKs) but doesn't change the fact at after a while I get this exception (I can see on WireShark that there is always a window problem right before the Java exception).
So how to I make sure in Java that my TCP windows/buffers are clear (Which I think is the root cause of the problem?) seems to be no flush on the DataInputStream. Make be wonder that whilst I might be reading it the TCP stack is filling up.
Many Thanks
Mark
I've attached the basic code calls below:
public void connectToServer()
{
//Create socket connection
try
{
if (lSocket == null)
{
lSocket = new Socket("localhost", 7651);
lSocket.setSoTimeout(0);
lInDataStream = new DataInputStream(lSocket.getInputStream());
lOutDataStream = new DataOutputStream(lSocket.getOutputStream());
}
}
catch (UnknownHostException e)
{
System.out.println("Unknown host: localhost");
}
catch (IOException e)
{
System.out.println("No I/O");
}
}
public void readSocket() throws IOException
{
//Receive data from ROS SerialtoNetwork server
if (lSocket != null)
{
lInDataStream.readInt();
lInDataStream.readFully(cbuf);
lOutDataStream.writeBytes("Ack");
lOutDataStream.flush();
//String lstr = new String(cbuf);
//System.out.print(lstr);
//System.out.println("");
}
}
public String getDataBuffer()
{
String lstr = new String(cbuf);
return lstr;
}
