Thanks Niklas! That makes sense. I was using the SumUp example as a
foundation for my code and it simply creates the needed objects in the
sessionCreated method. This is where I started going astray. Thanks again!
Michael
----- Original Message -----
From: "Niklas Therning" <[EMAIL PROTECTED]>
To: <[email protected]>
Sent: Sunday, September 10, 2006 1:16 AM
Subject: Re: Dumb Questions about MINA Implementation
Mike Grundvig wrote:
...
public void sessionCreated(IoSession ioSession) throws Exception {
ProtocolEncoder delimitedEncoder = new
TextLineEncoder(defaultCharset, terminator);
ProtocolDecoder delimitedDecoder = new
TextLineDecoder(defaultCharset, terminator);
ProtocolCodecFilter codecFilter = new
ProtocolCodecFilter(delimitedEncoder, delimitedDecoder);
ioSession.getFilterChain().addLast("protocol", codecFilter);
}
This all works fine, but it seems horribly inefficient to create a
filter, encoder and decoder for each and every connection established.
Particularly when the ioSession provides the concept of attributes
that can be used to store stateful data. Is my implementation actually
correct? It seems a better approach (from a performance standpoint)
would be to create stateless versions of those objects and tie them to
the IOAcceptor itself unless I'm missing something (which seems likely
at this point).
I've seen examples that add filters to either the ioSession OR the
ioAcceptor. What's the difference? Adding to the acceptor adds them to
all new sessions, is that correct?
Yes, you're correct. Adding filters to the IoAcceptor means that they
will be added to all session created from that IoAcceptor. I'd say that
I would either add the ProtocolCodecFilter to the IoAcceptor or use a
single ProtocolCodecFilter instance in my IoHandler like this:
public MyIoHandler() {
ProtocolEncoder delimitedEncoder = new
TextLineEncoder(defaultCharset, terminator);
ProtocolDecoder delimitedDecoder = new
TextLineDecoder(defaultCharset, terminator);
this.codecFilter = new ProtocolCodecFilter(delimitedEncoder,
delimitedDecoder);
}
public void sessionCreated(IoSession ioSession) throws Exception {
ioSession.getFilterChain().addLast("protocol", codecFilter);
}
Of course, for this to work TextLineEncoder, TextLineDecoder and
ProtocolCodecFilter must be stateless. Luckily they are.
HTH
--
Niklas Therning
www.spamdrain.net
