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As already pointed out learning UML is a good starting Point for a object-oriented language like Java.
I can recommend the book "Applying UML and Patterns: An Introduction to Object-Oriented Analysis and Design and Iterative Development" by Craig Larman [^] to learn about how to actually apply modelling in real scenarios.
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Not sure how to answer that.
If you are an experienced developer then at least some of the UML (presumably what you are referring to) should make sense. Like class diagrams and sequence diagrams.
Some of the others like package diagrams are ignorable. Only time I ever used that was in a tool specifically intended to be a full UML code generation and IDE (and it did not succeed.)
If you are doing this for a class, and not a job, you will not have the necessary experience to get the point of most of them. So you are going to just need to memorize and hope. Even so the class diagram should at least be generally obvious.
For me the only ones I use, as a developer and architect, are class, sequence, use case and rarely state. Keeping in mind of course that an Architect or Design document is not defined only by the diagrams but also requires a lot of verbiage to explain and tie the parts together.
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I'm not much of an Architect so I need some advise.
We have a home-grown very badly designed queue that buffers data for a legacy system. The data is sent to the queue and stored in a sql table then the host service takes the top item and attempts to send it on. Do not assume the receiving legacy systems are .NET or even SOA... I may need to drop this stuff to an XML file.  Fun right? On success, the queued item is archived.
I have the opportunity to rewrite this. I want this buffer to handle any type of request (not a rigid data structure) and we need to report on the meta-data in the queue. So, I basically want to store the message or serialized object in an XML field and keep meta data in a separate table to meet the reporting requirements.
I've been looking for a design pattern (factory?) that I can follow or an example project on how to do this. Please make a recommendation.
I'm also aware of msmq. I doubt the decision-makers would allow me to go this direction but this is my one opportunity to get their buy-in. Can someone help me by telling me if msmq is a good solution for this and, if so, point out an article as to why? I assume msmq can only interact with web/wcf services. Is that true?
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Joel Palmer wrote: I'm also aware of msmq
Be aware that msmq has a hard limit on the size of messages. Slightly less than 2 meg if I remember. You can break it up and send it but that introduces more complications, again as I remember, error handling becomes difficult in those cases. And is impossible for some routing strategies.
Additionally routing for msmq is built in which means it attempts to find its own route. And you must be aware of this as it can have significant impacts if firewalls are in place in production and the correct ports are not opened (seemingly everywhere.)
Joel Palmer wrote: The data is sent to the queue and stored in a sql table then the host service takes the top item and attempts to send it on
Why is that a problem? It means that back ups are already handled. How are you going to handle backups if you put the data into the file system?
Joel Palmer wrote: I have the opportunity to rewrite this. I want this buffer to handle any type of reques
You didn't specify any other actual request in your problem description. Don't generalize without real cases. It complicates things and at least some times makes actual usage with other cases more difficult rather than easier. If you do have actual cases then you would use that to first determine your requirements.
That said a message queue, of some sort, is already a general solution. They also support persistence (ones I have seen do) in either the file system or databases. You would need to look for a guaranteed delivery solution for your messages. That is something that must be specifically configured for any queue.
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Wrap your "payload" in your "meta-data", and add it to a System.Collections.Concurrent.ConcurrentQueue<t> hosted in a service-type application.
"(I) am amazed to see myself here rather than there ... now rather than then".
― Blaise Pascal
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Hello,
by rewriting a MFC App
In .NET I want to declare huge bulk data, which should be placed in the exe.
Because I see, with the resource techniques the access to data implemented with resource-techniques are only possible with streams,
I want to prepare the data, e.g. by declaring long arrays.
Have you a tip for me?
Thank You
Erhy
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Erhy wrote: Have you a tip for me?
Yes, do not do it that way. But without more detail of what problem you are actually trying to solve it is impossible to say more.
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the App is a speaking keyboard
and when a key is pressed the sound should
played immediately.
So the wave data has to be available in memory.
The App should start fast.
The only reason to port from MFC to WPF is
to have more beautiful dialog.
Erhy
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What "data types" are you working with?
The simplest array is a bit or byte array.
"(I) am amazed to see myself here rather than there ... now rather than then".
― Blaise Pascal
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the data are .wav files prepared for XAudio2.
The longest file has 163 KB
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Erhy wrote: Because I see, with the resource techniques the access to data implemented with resource-techniques are only possible with streams,
I want to prepare the data, e.g. by declaring long arrays.
So presuming that the arrays do not exceed some limit in .Net itself, which you would need to test...
1. Create the array(s).
2. Write code that wraps the array(s) in a Stream.
You might need several classes for 2 depending on the exact stream that you need but you can start with the 'MemoryStream' class and research it from that.
I would expect that you should experiment with creating a new stream each time or attempting to keep a single instance. The former shouldn't be a problem because you are using a memory blob so the object cost is low.
If there is some reason that your data is unusual you might need to create your own stream class.
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Thank you for thinking about.
I want to avoid streams, because with XAudio2 the usage of pointers is necessary.
XAudio2 cannot used straight with C# .NET, rather such interfaces are necessary:
[SuppressUnmanagedCodeSecurity]
[DllImport(XAudioDll, CallingConvention = CallingConvention.StdCall)]
internal static extern int XAudio2Create(IntPtr ptr, int flags, XAudio2Processor flags0);
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Not sure what you mean.
You mentioned streams so I provided a solution that allows for a stream but a in process one (not file based.)
With speech you are going to need to pass a large amount of binary data using some api. Any implementation is either going to do that via an array or a stream even if the exact implementation is hidden.
Presumably you have an API of a library not under your control and you are using it. If it takes a stream then you pass it a stream (my in process solution.) If it takes an array then you pass an array (which you presumably already know how to create.)
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I hoped for using pointers in unsafe mode of C#, but I failed.
Now in a test project I have 250 C# files in the form
namespace WavDatSpace
{
unsafe public static partial class WavDats
{
public static byte[] WAVEA = {
0,0,220};
}
}
and with VS the building of the project needs minutes,
also when I change only one file.
How to do it better?
Erhy
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Move your resources to a separate project and stop building it every time.
Bastard Programmer from Hell 
If you can't read my code, try converting it here[^]
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is it possible without DLL ?
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If you add a Gb worth of data, and change some code so it needs be recompiled, then yes, it will take long. If you don't want that then make sure it isn't compiled each time by splitting it into its own assembly.
Bastard Programmer from Hell
If you can't read my code, try converting it here[^]
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Thanks,
while developing I will make an extra DLL with data
and in the final version I will include the byte array with data
in the body of the exe project.
Erhy
modified 29-Aug-17 9:52am.
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I primarily work with WPF apps, so for now, let's limit this to that...
How would you tell other instances of your app that something has happened, or to take some action?
Example of messages might be:
- Force Logout
- Record added to table
- Record is locked/unlocked by a user
- User has logged in/out
I've been learning SignalR and this seems like the perfect tool for the job. Anyone have any other ideas?
If it's not broken, fix it until it is.
Everything makes sense in someone's mind.
Ya can't fix stupid.
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Kevin Marois wrote: How would you tell other instances of your app that something has happened, or to take some action?
I usually don't, but when forced to, I'd use a queue in the database and poll that. There'd be a slight delay, just as GMail has.
Kevin Marois wrote: Record added to table
I wouldn't; I dislike the idea of lists growing while you're working with it. Or worse, data changing while you are editing 
Kevin Marois wrote: Record is locked/unlocked by a user
Again, I wouldn't; has never been a problem to let the database handle that.
Kevin Marois wrote: User has logged in/out
I wouldn't; even if both apps are on the same desktop, only the active one (the one with input-focus) would be logged out.
Kevin Marois wrote: Force Logout
I wouldn't; the server would simply return an error-condition on the next request, similar to Sql Management Studio.
To answer the question; yes, it seems like SignalR is a usefull communication-package. Now running a compiled script on a webhost may have the advantage of being very cross-platform, I would certainly not call it "realtime". Anything sent to a browser and digested by JavaScript is very noticeably "not realtime".
Kevin Marois wrote: Anyone have any other ideas?
I think that SignalR might work better in a web-environment, for those who are building web-apps. For a desktop-application I'd prefer a simple socket (and not another dependency), unless there is a very compelling argument against it.
Bastard Programmer from Hell
If you can't read my code, try converting it here[^]
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Eddy Vluggen wrote: I usually don't,
I agree with that sentiment myself. I found myself questioning even the need for some of the posted examples in the OP. Certainly when someone suggests such a need I usually question why it is needed in the first place.
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jschell wrote: Certainly when someone suggests such a need I usually question why it is needed in the first place.
I doubt that the web has such need, but since someone built a solution, there will be specifications demanding this "realtime" logout.
Bastard Programmer from Hell
If you can't read my code, try converting it here[^]
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I suppose such a solution could be used if you had a system where you had to roll an update out at a certain point in time. Your server could send out the notification that the update needs to happen and log the application out - and yes, I have seen systems that do this in practice.
This space for rent
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I can see how that would be preferred to looking at an old UI with cached JS. Users all over the world would not be able to work with the product after the update, simply because they're still on an 'old page'.
Not a problem to update Sql Server and disconnect some clients if you're on a desktop
Bastard Programmer from Hell
If you can't read my code, try converting it here[^]
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Pete O'Hanlon wrote: Your server could send out the notification that the update needs to happen
I can see several potential problems with that solution.
1. What if the client app does not receive the notification.
2. What if the client app is in the process, right at that moment, of making a request to the server.
3. As a specific example of 2 what if the app is in the process of doing a long running process, such as uploading or downloading a large file.
4. What happens if the update is actually to the notification service itself?
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