Would be nice if this stuff could do ASN.1 to pack(). Perhaps that is
something they
may look into.
Alex
On 7/24/07, Mehmet D. AKIN <[EMAIL PROTECTED]> wrote:
On 7/24/07, Trustin Lee <[EMAIL PROTECTED]> wrote:
> Hi Rodrigo,
>
> On 7/24/07, Rodrigo Madera <[EMAIL PROTECTED]> wrote:
> > Please tell me this wheel is invented and ready in MINA!!
> >
> > Here is the scenario taking as an example the SumUp server (the
closest
> > thing to the case).
> > Let's suppose there is this project called MegaMath, which is kind of
like
> > SumUp but has more operations:
> >
> > public class MegaMathMessage {
> > private byte opcode;
> >
> > MegaMathMessage(opcode) {
> > this.opcode = opcode;
> > }
> >
> > ...
> > }
> >
> > public class MultiplyMessage extends MegaMathMessage {
> > private byte operand0;
> >
> > MultiplyMessage()
> > {
> > super(Constants.MULTIPLY_OPCODE);
> > ...
> > }
> >
> > ...
> > }
> >
> > public class DoSomethingReallyNiceWithThreeArguments {
> > private int arg0;
> > private short arg1;
> > private byte arg3;
> >
> > // ... initialize with ctor etc...
> > }
> >
> > Now that we have the variable parameter quantity messages, we could
write
> > the decoders and encoders, but that's not nice.
> >
> > So the part we are writing let's us do basically this:
> >
> > NiceEngine.register(MultiplyMessage.class);
> > NiceEngine.register(SingASongMessage.class);
> > NiceEngine.register(DanceMessage.class);
> >
> > MessageEncoder multiplyMessageDecoder =
> > NiceEngine.getDecoder("MultiplyMessage");
> > // classname or class can be used here.
> > MessageDecoder multiplyMessageEncoder = Nice... you get the
point...
> >
> > Is this available?
>
> It's not available. I think it's difficult to generalize.
>
> > The problem is that manually creating Decoders and Encoders is just a
waste
> > of time. This should be a machine's work, and this is what our design
is
> > promissing to aid us in.
> >
> > We tried using Javastruct, and even devoted three full days to writing
code
> > for it, but we came to the conclusion that we needed more and in a
more
> > structured manner, so we started this solution.
> >
> > If this is already implemented, please share some light on how to use
it.
>
> You could forward your feedback about JavaStruct to Mehmet so he can
> evolve it on and on. :)
>
> Thanks,
> Trustin
> --
> what we call human nature is actually human habit
> --
> http://gleamynode.net/
> --
> PGP Key ID: 0x0255ECA6
>
Hi,
I agree with Rodrigo on writing protocol encoders and decoders is
quite tedious job. That was the reason I was thinking something like
JavaStruct might help on these situations. He also helped me to find
some bugs and had some nice insight on the architecture. Thanks a lot.
Although Rodrigo and his team found JavaStruct is not enough to handle
their problems, I still have a feeling that JavaStruct can be helpful
on many situations. Please look at the example codes below. There are
two examples, an Adobe Photoshop color book binary file reader -
writer and a Mina example. Mina example is based on the nice protocol
encoder-decoder tutorial on the wiki and it is not complete yet, but
if you look at the code you will get the idea.
Examples: http://javastruct.googlecode.com/svn/trunk/javastruct/samples/
I also updated how-to documnent in the wiki. there is also usable 0.1
jar in the downloads section.
IMHO, Rodrigo's approach, (If I have gueesed correctly), automatic
generation of encoders and decoders have good and weak sides. It
probably generates code with better I/O performance (since for every
type of message, there will be an encoder-decoder generated
automatically, reading and writing directly to mina byte buffers. But
generating code has always drawbacks, difficult to maintain and
implement and sometimes considered as an anti pattern. I hope they
achieve good results and share their results with us.
regards
Mehmet
