I was wondering if anyone had experience retrieving data with the 3270 protocol. My understanding so far is:
Connection
I need to connect to an SNA server using telnet, issue a command and then some data will be returned. I'm not sure how this connection is made since I've read that a standard telnet connection won't work. I've also read that IBM have a library to help but not got as far as finding out any more about it.
Parsing
I had assumed that the data being returned would be a string of 1920 characters since the 3278 screen was 80x24 chars. I would simply need to parse these chars into the appropriate fields. The more I read about the 3270 protcol the less this seems to be the case - I read in the documentation provided with a trial of the Jagacy 3270 Java library that attributes were marked in the protocol with the char 'A' before the attribute and my understanding is that there are more chars denoting other factors such as whether fields are editable.
I'm reasonably sure my thinking has been too simplistic. Take an example like a screen containing a list of items - pressing a special key on one of the 24 visible rows drills down into more detailed information regarding that row.
Also it's been suggested to me that print commands can be issued. This has some positive implications - if the format of the string returned is not 1920 since it contains these characters such as 'A' denoting how users interact with the terminal, printing would eradicate these. Also it would stop having to page through lots of data. The flip side is I wouldn't know how to retrieve the data from the print command back to Java.
So..
I currently don't have access to the SNA server but have some screen shots of what the terminal will look like once I get a connection and was therefore going to start work on parsing. With so many assumptions and not a lot of idea on what the data will look like I feel really stumped. Does anyone have any knowledge of these systems that might help me back on track?
You've picked a ripper of a problem there. 3270 is a very complex protocol indeed. I wouldn't bother about trying to implement it, it's a fool's errand, and I'm speaking from painful personal experience. Try to find a TN3270 (Telnet 3270) client API.
This might not specifically answer your question, but...
If you are using Rational Developer for z/OS, your java code should be able to use the integrated HATS product to deal with the 3270 stream. It might not fit your project, but I thought I would mention it if all you are trying to do is some simple screen scraping, it makes things very easy.
Related
I am going to research on which key typed most in which hour in a 24-hour-day?
Later, I would research on which word used most in which hour in a 24-hour-day?
Say in the evening you would find most used word good or bye as people usually ends up their meeting in the evening.
So, I need to record keystrokes on the background using a java application with a time-stamp.
My questions are:
How to run a java program on the background?(Obviously informing the user).
How to record keystrokes which are used in other applications and counted in the java application without affecting its original application?
Note that:
This question does not serve my problem. Though it has an accepted answer, but the answer is not helpful for me because it could not distinguish between uppercase and lowercase letter, it returns same ASCII character. It just gave some sources and some other files. I expect more readable answer and a clear view how the java program launch on the start up and run on the background.
Just a little information to get you moving in the right direction. What you are looking to implement to listen for the keystrokes is KeyListener. I believe the actual function is keyTyped(ActionEvent e) but am not sure.
Other then that to run a program silently in the background will probably require some manipulation of the window + windows properties. You could just have the program run without a UI, or create a very lightweight UI that posts data. If you are looking for an actual "out of sight out of mind" background process, I am not sure how to do this with Java. However I imagine just an un-intrusive GUI would be sufficient for your purposes.
The NeuralDataSet objects that I've seen in action haven't been anything but XOR which is just two small data arrays... I haven't been able to figure out anything from the documentation on MLDataSet.
It seems like everything must be loaded at once. However, I would like to loop through training data until I reach EOF and then count that as 1 epoch.. However, everything I've seen all the data must be loaded into 1 2D array from the beginning. How can I get around this?
I've read this question, and the answers didn't really help me. And besides that, I haven't found a similar question asked on here.
This is possible, you can either use an existing implementation of a data set that supports streaming operation or you can implement your own on top of whatever source you have. Check out the BasicMLDataSet interface and the SQLNeuralDataSet code as an example. You will have to implement a codec if you have a specific format. For CSV there is an implementation already, I haven't checked if it is memory based though.
Remember when doing this that your data will be streamed fully for each epoch and from my experience that is a much higher bottleneck than the actual computation of the network.
I know there are other posts about this, but I cannot seem to find one strictly for handwriting. I am going to have a form and all I need to read in is 8 squares in the left hand corner that will have 3 letters proceeded by 5 numbers.
The problem with most posts is that people either post about software for writing on the screen or software that doesn't recognize handwriting yet. I would prefer to have something in java, but something simple in another language would work.
What would really work is if people could scan their documents and just type the job number for the document name, but apparently they cant do that right...
Can you change the form? This problem will simplify a lot if you can change the form to be something that is easier for a machine to read. To recognize an arbitrary handwriting is hard as well as error prone.
What I have in mind is a form like this:
form example http://shareworldonline.com/w3/testprep/images/test%20form.jpg
However, if you have to have handwriting, check out the solutions in this thread.
if i got you correctly, you are doing offline hwr,
when i was doing offline hwr, i found most difficult separating characters in word, seems like you have them in squares, so all what you need to do is find your boxes (ie by using histogram)
and compare content of your box with each element in yours characters database (i used levenshtein distance for that)
I know it maybe not very helpful, but maybe push you on right track.
I'm trying to develop a system whereby clients can input a series of plant related data which can then be queried against a database to find a suitable list of plants.
These plants then need to be displayed in a graphic output, putting tall plants at the back and small plants at the front of a flower bed. The algorithm to do this I have set in my mind already, but my question to you is what would be the best software to use that:
1) Allows a user to enter in data
2) Queries a database to return suitable results
3) Outputs the data into a systemised graphic (simple rectangle with dots representing plants)
and the final step is an "if possible" and something I've not yet completely considered:
4) Allow users to move these dots using their mouse to reposition if wanted
--
I know PHP can produce graphic outputs, and I assume you could probably mix this in with a bit of jQuery which would allow the user to move the dots. Would this work well or could other software (such as Java or __) produce a better result?
Thanks and apologies if this is in the wrong section of Stack!
Your question is a bit vague. To answer it directly, any general programming language these days is able to do what you want, with the right libraries - be it C/++, Java, PHP+Javascript, Python, Ruby, and millions of others
With Java in particular, you'll probably want to use the swing toolkit for the GUI.
If you do know PHP+Javascript exclusively, it's probably best for your project to stick to what you know. If, however, you see this more as a learning opportunity than a project that needs be done NOW, you could take time to learn a new language in the process.
As to what language to learn, each person has a different opinion, obviously, but generally speaking, a higher-level a language is faster to prototype in.
EDIT
If you need this for a website, however, you'll need to use something web based - that is, you'll necessarily have two programs, one that runs server-side, the other one in the client (browser). On the server side, you could very well use PHP, JSP (JavaServer Pages), Python or Ruby. On the client side, you'll be limited to Javascript+DOM (maybe HTML5), a Java applet, or something flash-based.
An Android app I'm writing involves quite a lot of downloading of content (think podcatcher/RSS).
I would like to be able to give the user an indication of how many bytes they've downloaded, so they can make the decision whether they want to use Wifi or not.
To this end, I have found a way of counting the number of bytes read by the app, by wrapping an InputStream in a simple CountingInputStream.
However, this does not take into consideration basic things like packet headers and HTTP headers. More importantly, it does not take into consideration any compression that content may be encoded with.
So, how many bytes did my application download over the network? I'm not so interested in the number of bytes uploaded, but if know how, don't be shy.
I have gone down a fairly low level approach as I am feeding the input stream into an XML PullParser. I will also be needing to do a similar exercise with dumping bytes (images in this case) straight onto the SD Card.
Is this the best approach? What am I missing?
ufff... I think this is pretty transparent to underlying protocol, so you can't count all these bytes used in session or link layer, and operators like to charge even for control bytes which are not in any way visible to end user. Also they count traffic in both directions (your reqest to server takes also some), so - good question is: how to measure needed traffic/money for downloading that picture... ?
This isn't a direct answer, but you could try asking someone who has solved a similar problem before, e.g. a data counter application. I've used NetCounter by Cyril Jaquier (http://www.jaqpot.net/netcounter/), and he claims his software is open source. I couldn't get his download link to work, but there's a contact email address. If you got his source code, you should be able to use the same method as him.
As I know, there are two ways to count data traffic. One is /sys/class/net/{interface}/statistics as mentioned in android app named netCounter, the other is /proc/net/dev which is used in android app named wifi-tether. But I don't know the difference between these two methods nor which is better.
The number of bytes received by a particular app is stored in /proc/uid_stat//tcp_rcv where app_uid is the uid of your app on the particular device.