I would like to know, if it is possible to build an application using WSO2. The problem is I need to receive sensor data’s from different devices. Process those data’s in real time and store meaningful information’s semantically using OWL. I am little confused with the type of WOS2 products that I need to consider for developing thise kind of application. In future I need to scale up this system with increase in devices.
You may take a look at WSO2 Complex Event Processor (CEP) for real-time event processing requirements. Please go through the documentation to get an idea.
http://docs.wso2.org/wiki/display/CEP210
Thanks,
Dileepa
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I hope you are doing good and i really appreciate your help here for my query.
We have our system T3000 written in C++ (http://www.temcocontrols.com/ftp/software/9TstatSoftware.zip and codes are available here https://github.com/temcocontrols/T3000_Building_Automation_System).
I am trying to integrate 'BIRT reporting tool' in my C++ application. I want to create report based on the data available in our T3000 system. I think BIRT is embeddable (??). We don't need to compile and change the project, just need to be able to call it from T3000.exe mainly.
My thinking is we may put one menu label in existing T3000 and try to display report in user single click.
Can you please help me to solve my issue with 'BIRT' ? I really appreciate your answer.
Regards
Raju
Well, the answer depends on what your definition of "embeddable" is.
BIRT is written in pure Java.
I could think of 3 different ways:
Of course it is possible to integrate Java code into an existing C/C++ program (see Embed Java into a C++ application?).
You could just use the BIRT runtime engine and generate the report as PDF or HTML from the command line (that means, basically you call the java executable from your program with several arguments). See Birt - How to run report engine on the console? and http://eclipser-blog.blogspot.de/2008/02/automatic-generation-of-birt-reports.html for more information.
You could run a Java web server like Tomcat in a second process and then start your report by calling a http URL (e.g. you could use the included Servlet example). See http://www.eclipse.org/birt/documentation/integrating/viewer-usage.php
Similar to 3. (see below)
Some notes:
The second option is slow, due to the Java and BIRT engine startup overhead (this may take several seconds). With the first and third option, the startup overhead is or can be minimized to only once (and for each report).
For the second and third option it may be necessary to modify the existing code of the example programs to suit your needs.
The first option is probably the best for an industry-quality solution, but it is also the most difficult to develop.
Anyway, Java skills are necessary IMHO.
If you plan to run this on a SOC instead of a PC, take performance into account.
Is a Java-based solution well-suited for this kind of hardware? BIRT needs quite a lot of RAM and CPU (for a SOC). Hardware like the Raspi 3 should handle this quite easily, I reckon.
I integrated the BIRT runtime into an existing Python application (all this running on an application server) in a fourth way: I wrote a listener program that listens on a TCP socket for BIRT tasks. It uses a pool of worker processes (written in Java) which in turn use the BIRT report engine to generate the output. The client program (here: written in Python) opens a TCP connection to the listener and uses this socket to tell it which report to generate (including report parameters and destination file name). The listener program then in turn chooses a worker process for the task and gives the task to the worker process.
So, basically, this fourth option is similar to the third one, with two differences:
The communication is socket-based (instead of http), allowing bi-di communication.
The architecture is multi-processes instead of multi-threading. We choose this because very large reports could cause out-of-memory errors for otherwise unrelated reports that just happen to run at the same time. It's the same basic architecture Oracle chose for their reports server.
However, developing the programs took months.
HVB: I have to give you more than a simple thanks for the explanation above, this info will save us time I am sure. Raju will be sharing our experience after we get into the project a little deeper so others can benefit.
I have an interesting conundrum. I have been challenged with identifying the most suitable process in which to create a "browser front-end" to an existing multi-user application built within the TigerLogic/Pick D3 environment. My research indicates there are many ways to do this; but I am struggling to decide which method is best or where to start. I have "played" with a few technologies but a commitment to one is needed to get started.
These methods include:
Creation of a complex webservice using MVS Toolkit; and engineering a client from WSDL either from scratch or using maven/wsimport. Tests indicate there is a lot more to this process than originally though for a simply WSDL.
Development of a Java based web app that harnesses the MVSPJavaAPI - I am not a JAVA developer so this means learning a new language. Development would most likely take place in Eclipse.
Using TigerLogics FlashCONNECT - resulting in additional expenditure to clients so not preferable - and more or less ruled
out.
There is also the .NET option - but I have ruled this out on the basis of needing portability.
My question is, has anyone else out there done anything like this and could you share your experience? My first task is to build a web-app that will reliably give me the D3 TCL prompt in a browser that I can customise.
I am not sure there is a definitive answer here but would like peoples thoughts and will label the most useful as the answer.
What path you choose depends in some part on your existing skill-set and whether that fits in with your portability needs. It is very difficult to give you a concrete answer to your question becaue of not knowing in which part of the chain you need the portability.
It is however possible to develop a web-browser front-end using .NET which will run on Linux or Windows, so I don't see an issue with portability here. Your web server will have to be windows based but it shouldn't matter whether D3 is running on Linux or Windows at the server-end, or whether the client desktops are running Linux or Windows.
You could try TigerLogics MVSP .NET API but I do not know if it has the power to deliver based on your needs. I believe you may find mv.NET from Bluefinity could fulfill your needs. This is in my opinion the leading product on the MultiValue market for achieving the goals you have in mind. This will mean spending money of course. For this you will get a very powerful set of tools. Also, the cost of investing in a good tool could end up smaller than the cost in terms of time, effort and potential complications of trying to do this piecemeal without spending any extra money. I am sure Flashconnect would also do the job. You would have to weigh up the cost of the different options to find out which one is right for you both technically and financially.
Not knowing whether or not you have .NET in your skill-set, I don't know whether the .NET option would be easier for you. It is however technically possible.
I would suggest using Rocket's D3 (formerly TigerLogic D3) .NET APIs and create a Web API RESTful service that you can consume with JavaScript in any other web technology and if you need to call from a D3 subroutine (in case you would) then use the MVS Toolkit.
Requirements though are D3 9.0 or later.
I've used all of the technologies described, and many more to interface with D3. I agree with #Glenn and will add... I understand you're edging away from .NET. That's fine, you don't need it. But consider that most LAMP implementations separate the DBMS servers from the web servers. That topology introduces short delays between the tiers but decouples them in case you want to use multiple web servers or multiple databases - a common topology even with D3 / MV.
I have a client where we have a Java/Grails front-end over Linux, with all data queries filtered through a single, elegant data provider class that's abstracted from application logic. That uses a web service call which I wrote in Java, calling to a .NET web service. The service is easily generated/modified, as is the client from the WSDL. From there IIS carries inbound queries to D3 via mv.NET, and at this point it doesn't matter if the D3 DBMS is in Linux or Windows. My web service could have as easily been in Linux with Java but it would then lack a pooling mechanism - see below.
If you want all Linux then you can go with the MVSP Java library. TigerLogic (now acquired by Rocket Software) committed to a PHP binding for MVSP some months ago. Rather than wait, one of my clients created a PHP wrapper around mv.NET, though MVSP is as easy. So the resulting application is essentially LAMP, but with the M = Multivalue. I have written code like this too - we can write a wrapper in any language which exposes a useful API and abstracts both connectivity method and OS dependencies. In other words it doesn't matter what languages we want to use or what OS's are involved. That part is rather trivial and subject to change later. It's better to focus on the application than the communications.
You can also go off the menu, so to speak, and create your own Java/PHP wrapper around the OS-level d3tcl command, which is a script/wrapper around the d3 executable. This allows you to open a connection yourself and pass in commands.
Whatever option you select, you need to consider that opening and closing a DBMS connection is a slow process. You do not want to script a login around every data request. You do want to open a connection and keep that open persistently, while your client code accesses and releases that persistent connection as required. This is why we like mv.NET and FlashCONNECT. With MVSP and other mechanisms you need to create your own persistence model. You'll also need to manage a pool of connection resources - what happens when you get 10 simultaneous queries, or just 1 short one after one long one? You don't want queries to back up, you don't want to reject or timeout connections, and you don't want to fire up a connection for every client. You do want the proper number of DBMS sessions waiting for inbound connections. mv.NET and FlashCONNECT do this for you, the others do not.
Personally I'd shy away from FlashCONNECT. I was there for its initial development and testing and for years of end-user implementations. It's not as widely used as the other options and is more a tool for those who aren't familiar with other options. If you're talking about Java then you're probably not inclined to use FlashCONNECT. That said, if you have developers who are not familiar with anything outside D3 then FlashCONNECT is a decent server-side tool for them while someone else is focusing on the client-side with other technologies. Everyone should use their best skillset.
Finally, (already?) if someone is not familiar with external technologies, and more intimate with D3, then other options exist like DesignBAIS and Viságe, mostly removing the burden of communications and allowing developers to work on the client-side features and back-end rules in BASIC.
I discuss all of these topics plus mobile and telephony on my blog.
HTH
I have made an application in C++ and would like to know how to go about implementing a usage statistics system so that I may gather some data regarding how users use the program.
Eg. IP Address, Number of hours spent in application, and OS used.
In theory I know I can code this myself if I must, but I was wondering if there is a framework available to make this easier to do. Unfortunately I was unable to find anything on google.
Though there is no any kind of such framework, you could reduce the work you have to do (in order to retrieve all these information) by using some approaches and techniques, which I tried describe below. Please, anybody feel free to correct me.
Let's summarise, what groups of information do we need to complete the task:
User Environment Information. I suggest you to look at Microsoft's WMI infrastructure, in particular to WMI classes: Desktop, File System, Networking, etc. Using this classes in your application can help you retrieve almost all kind of system information. But if you don't satisfy with this, see #2.
Application and System Performance. Under these terms I mean overall system performance, processor's count, processes running in OS, etc. To retrieve these data you can use the NtQuerySystemInformation function. With its help, you will get an access to detailed SystemProcessInformation, SystemProcessorPerformanceInformation (retrieves info about each processor) information, and much more.
User Related Information. It's hard to find a framework to do such things, so I suggest you simply start writing code, having in mind your requirements:
counting how many times each button was pressed, each text field was changes, etc.
measuring delay time between consecutive actions in some kind of predefined sequences (for example, if you have a settings gui form and you expect from the user to fill very fast all required text fields, so using a time delay measuments can give you an information if the user acted as we expected from him or delayed after TextBox2 for a 5 minutes).
anything that could be interested to you.
So, how you could implement the last item (User Related Information) requirements? As for me, I'd do something like folowing (some may seem very hard to implement or too pointless):
- creating a kind of base Counter class and derive from it some controls (buttons, edits, etc).
- using a windows hooks for mouse or keybord while getting a child handle (to recognize a control, for example).
- using Callback class, which can do all "dirty" work (counting, measuring, performing additional actions).
You could store all this information either in a textfile or an SQLite database or there wherever you prefer.
I would recommend taking a look at DeskMetrics. This StackOverflow post summarizes the issue.
Building your own framework could take you months of development (apart from maintenance). With something like Trackerbird Software Analytics you can integrate a DLL with your app and start tracking in 30 minutes and you get all the cool real-time visualizations.
Disclaimer: I am affiliated with company.
Systems which require communication between disparate applications is quite commmon.
What is the normal architecture for such applications? Am I right in thinking that web services are the usual tool (if so, what reasons why?).
Also, what other considerations are involved?
Thanks
There is no normal architecture and web services is certainly one way to link them up anda popular one. But the communications technllogy choice is a trivial part of this problem.
Who is communicating what, when and why, is the head scratcher, and of course we can't answer that in anything but the most general of terms.
You need to start with the type of interactions between the applications.
Just retrieving data from another aplication
Requesting another application to perform some function, no feedback of any kind required
Transactional. Do something with this and return a response (synchronous and asynchronous).
Are these applications yours? If so you should head towards SOA. ie you take the processing out of the application, make it a service and then request it. All your other apps then can also request it.
However you go there is no easy solution, because these applications were not designed to work togther.....
Even though I've been in Java SE for quite some time now, I started EE & web w/ Java only about a month ago, so pardon if the question seems a bit noobish...
So here's the situation: I'm trying to write a JS based multi-player game with real-time interaction (let's say chess in this example, though it really doesn't matter what particular game it is, could be tennis or w/ever). The clients would interact with the server through JS calls, sending the move etc. Now, while I could just receive the move from one client & pass it straight on to the other player, not maintaining the game state on the server would mean putting a huge sign out saying "user JS scripts welcome" (and that's out of experience -- "hacked" a crapload of that kind myself). This brings me to my problem -- how do I share a stateful object between several sessions? One idea that came to mind was a singleton storing a Hashmap of stateful beans & then each session could retrieve the bean by it's hash, but I've no idea how right that is (and it seems rather complex for a fairly common thing like that). Tieing it to application scope seems overkill as well...
P.S. I do understand that the object would need concurrency managing etc, I just can't seem to put my finger on how to get it shared...
EDIT: I'm sorry I didn't mention it before -- using Glassfish, EE6.
You have a business process scenario which is defined according to Seam framework documentation as follows
The business process spans multiple interactions with multiple users, so this state is shared between multiple users, but in a well-defined manner. The current task determines the current business process instance, and the lifecycle of the business process is defined externally using a process definition language, so there are no special annotations for business process demarcation.
Here you can see a Seam business process management Tutorial
Notice Seam uses JBoss BPM behind the scenes to handle its business process context. If you just want to use plain JBoss BPM capabilities, you can see here how to integrate with JBoss
See also JBoss BPM User guide
Solved. Shared it via ServletContext, which I initially thought wouldn't work 'cause FacesServlet is a separate one, thought it has smthn like a different container either.