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
