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How to get started reading data from magnetic card with a simple bi-direction swipe magnetic card reader?

Let's say I have a USB magnetic card reader
(http://image.ec21.com/image/szttce09/oimg_GC03950917_CA03950946/Triple_Track_USB_Magnetic_Credit_Card_Reader.jpg)
I am running windows 10 on my machine. All I want to do is read data from the magnetic card and use that data in a java Application. How can I do this ? I heard the java communications api is suitable for what I want. How exactly do I use this api or any other api to read data from the card reader and show that data in my java application. Assume I have eclipse opened. Now what? Do I import the communications api ? If yes , what do I do next ? If you can give a simple example of how to do this it would be greatly appreciated.

The first thing to do is search the internet for a Java library, which allows you to communicate with that device. Put in the model and serial number, and see what comes up. If nothing comes up, and that is quite likely to happen, you will need to find the native driver, and wrap it in Java.
This is not normally a straight forward or easy process. When dealing with third party hardware, most vendors don't supply a little Java library that you can use. If you can find the native drivers, you can wrap them from C to Java, but you might not even be able to find the drivers at all.
Start by going to the manufacturer's page, and looking around. If you find the driver, great. If you find documentation for the driver, even better. You will need to read the documentation, and understand how to use the driver from C code, which implicitly requires you to have a basic understanding of C.
Then you will need to link it in to Java, using the Java Native Interface.
In Summary: If it didn't say "For Java developers" in the description when you bought it, you're going to have to do a lot of work just to get it usable in Java.

How to access information in Windows Device Manager from Java?

I have a serial to USB device and more than one of those can be connected to the computer. I need to query and retrieve a list of COM ports that the devices are connected to. In Windows Device Manager you can get the COM port + friendly name of devices that are connected at the present time. This list is dynamic.
Reading from the registry did not work because the information stored is stale and static, not dynamic.
Devcon (from Microsoft) does list the ports that devices are connected to, but it cannot be used in my app because it is not re-distributable.
Any ideas or preferably, a solution?

I had to solve a similar issue just some weeks ago. I came accross the Jawin-Project that provided everything you need to use WMI-Queries. It is already quite old but works like a charm if you follow the documentation. A nice German walkthrough can be found codegods blog.
For me, it did not solve all problems (I had some very specific things to find out about the target device), I finally created an own JNI (Java Native Interface) Class and DLL in C incorporating the windows API.
I hope this is what you searched for.

Did you try this jUSB API or This example ?
I hope this will help you.

Use JNA (https://github.com/twall/jna) and take a look at the following page. It might be a useful point to start from.
http://www.digitalinferno.com/wiki/Wiki.jsp?page=JNAPrintDevices

I am looking at Java Native Access as it provides access to the windows API from pure Java code - no JNI to deal with. I was concerned about the LGPL license; whether it can be included in a commercial product but from what a few posts in the newsgroup say, it can be.
After I try it out in the next few weeks, I shall post back here.

Programming a GSM phone/modem to make phone calls

I want to use a program written in a high level language like Java or Python to talk to a GSM Modem.
I want to be able to tell the modem what number to call and when to call it. I also want to be able to read and send text messages.
I do NOT need to handle voice transmission in either direction of the call.
I'd appreciate recommendations of any applicable libraries and specific modems that are good to start with? I like Java but am willing to try something else.
Thanks

There are a set of relatively standard "AT" commands that can be used for these types of operations - including placing phone calls and sending text messages. Some details around this are at http://www.smssolutions.net/tutorials/gsm/sendsmsat/ and http://www.dreamfabric.com/sms/ (simply first results of a little online searching).
A little more online searching yielded a Java-specific example at http://www.java-samples.com/showtutorial.php?tutorialid=22 .
I had done a little bit of this in Java a number of years back, using the Java Communications API - available at http://www.oracle.com/technetwork/java/index-jsp-141752.html . (My purpose was for interfacing with the phone book on my phone, but this also should have worked with interfacing with the SMS system.)

Almost all modems and (phones which support tethering to your PC) can do this. All modems are equally good at it.There are no starter's modems. Just go through the AT commands specific to your applications and thats it.

printing to a dot matrix printer on a mac

So i am designing an art project that will print to a dot matrix printer the contents of my internet history. i have found info online to parse out a plist (what os x uses to store internet history) so im all set on that front but what i am looking to find out is how to send a request to the printer to print a new line, which would happen when a new page is visited. i was wondering if it is possible in any of the following languages: objective-c, javascript, php, or processing/java, all of which i have a decent understanding of. I am have tried to do a little research before asking here and it seems like i may need to use shell commands, which i am not familiar with at all. the printer i will most likely be using is an EPSON LX-300 Dot Matrix Printer if that matters. i would like to do this on os x, but if i have to use windows that is an option. if anyone knows how to do this or can give me some direction that would be a huge help. thanks

Here is how I might do it.
First, I suppose I might look around for a dot matrix printer with a modern interface and a Mac OS X driver. There might still be people printing multipart forms who need impact printers.
But failing that, I would then look for a serial (as in, RS-232 serial) printer and connect it to my mac via a USB-to-RS232-serial converter. Be careful, most of the generic such things don't work on the Mac, get a USB serial widget like this that specifically supports the mac.
Then, I would write the code in sh/bash and run it in a Terminal window. Those language systems you cite are overkill for this job, some lack system interfaces entirely, and the ones that can turn system knobs do it via complex interfaces. It's better to put together stty(2), echo(1), cat(1) et al and just get some strings to print.

Java VNC Applet vs Screen Capture

I am trying to make an application in which one component captures the screen of the user (for screen casting). I am aware that there are two options to achieve the same using a Java applet (please correct me if I am wrong). First is to use the java applet to take screen shots continuously and convert it into a video and upload it as a video file. And second is to create a java vnc server and record it as a .fbs file and play it using a player like: http://www.wizhelp.com/flashlight-vnc/index.html
I would like to know the best solution in terms of video quality, file size, cross-platform compatibility (windows and mac), firewall problems and finally ease of implementation.
I am very new to Java. Please tell me whats the best solution for my problem. Also, is it easy enough for me to program it on my own or should I get it developed via a freelancer. I have tons of programming experience (5+ years in LAMP) but none in Java.
Thank you very much.

I agree that this is pretty hard. I implemented those two solutions (VNC and onboard screen capture) plus a third (capture from an external VGA source via an Epiphan grabber) for a former employer. I had the best bandwidth-to-quality ratio with VNC, but I got higher framerate with VGA capture. In all three cases, I reduced the frames + capture times to PNGs and sequenced them in a QuickTime reference movie. Then I made flattened video (MPEG4 or SWF) of the results. In my case, I then synchronized the screen video with a DV stream.
In the end the technology worked (see a sample of the output) but our business model failed.

From what I know, the older versions of applet had security restrictions that may not allow for screen capture. Instead, a java application may be feasible.
Regarding the build-it-yourself vs the fire-a-coder, it depends on how you value your time compared to what you can find on a freelancer site.
I think you can find someone from India/Romania/Poland/Other countries that can make it for an affordable price

Given your Java knowledge and the difficulty of the task, have you considered taking an alternative approach? For example, how about a native VNC server for the end-user, which is just a small download and then they click "Run." And that native server is programmed to capture the screen and send it straight to your web server, which has a client like vnc2swf or other means of converting the VNC stream to a video or .fbs file? Does all that make sense?
Admittedly, without Java, you have to prepare one executable program per platform you want to support, however, I don't know. That still sounds easier to me. Consider Copilot.com. They are doing VNC but they still use small native apps for each platform.

Sorry but this seems the kind of job that requires a lot of experience. Even if you find code snippets all around the net to fix this and that, the overall result may be way worse than simply hiring an experienced Java programmer.