Is it possible to have JavaScript which calls a Java file (or something of the sort), so we can connect to a Bluetooth device and send it commands from a web page?
If it is possible, what are some ideas behind it that I can use to get it working?
Sorry for my poor language, I am not really sure how to word it.
Java can be used to send files via Bluetooth, and there is a tutorial on it at http://today.java.net/pub/a/today/2004/07/27/bluetooth.html
You could run a Java applet from the web browser that would use Bluetooth, although it would probably come up with a warning asking if you want to give the applet access to the files on your computer. JavaScript, however, would not be necessary, since an applet can run directly on a webpage.
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I want to do something like a bot for WhatsApp (Desktop Version) that automatically responds to other people's messages, but I don't know how to read the text out of an external program. Is this even possible in Java? If yes, does anyone know how to do this (without WhatsApp API)?
The desktop version of whats app is a web app wrapped into a client app. It is similar to https://web.whatsapp.com. You can use Selenium to access the HTML with Java.
I wish to control my computer (and usb devices attached to the computer) at home with any computer that is connected to the internet. The computer at home must have a program installed that receives commands from any other computer that is connected to the internet. I thought it would be best if I do this with a web interface as it would not be necessary to install software on that computer. For obvious reasons it would require log in details.
Extra details: The main part of the project is actually a device that I will develop that connects to the computer's usb port. Sorry if it was a bit vague in my original question. This device will perform simple functions such as turning lights on etc. At first I will just attempt to switch the lights remotely using the internet. Later on I will add commands that can control certain aspects of the computer such as the music player. I think doing a full remote desktop connection to control my device is therefore not quite necessary. Does anybody know of any open source projects that can perform these functions?
So basically the problem is sending encrypted commands from a web interface to my computer at home. What would be the best method to achieve this and what programming languages should I use? I know Java, Python and C quite well, but have very little experience with web applications, such as Javascript and PHP.
I have looked at web chat examples as it is sort of similar concept to what I wish to achieve, except the text can be replaced with commands. Is this a viable solution or are there better alternatives?
Thank you
VNC
SSH
Remote Desktop (Windows)
You can write a WEB APPLICATION. The encryption part is solved by simple HTTPS usage. On the server side (your home computer with USB devices attached to it) you should use Python (since you're quite experienced with it) and a Python Web Framework you want (I.E. Django).
While it is an interesting programming question, perhaps you should ask it on ServerFault instead? There you can probably get a lot of nice input on web-based administration / control tools.
Unless this is a "for fun" project for you, there are about a jillion things out there that already do this. And if you want to control a computer from a web browser, be prepared to require installing some kind of custom plugin - since browsers can't touch arbitrary files on the local filesystem, execute local applications, or do other things that are flagrant security risks.
I've been using VNC for over a decade - free and easy.
http://en.wikipedia.org/wiki/Virtual_Network_Computing
Well, I think that java can work well, in fact you have to deal with system calls to manage usb devices and things like that (and as far as I know, PHP is not the best language to do this). Also shouldn't be so hard to create a basic server/client program, just use good encryption mechanism to not show commands around web.
I you are looking for solution you could use from any computer anywhere in the worls without the need to install any software on client pc, try logmein.com (http://secure.logmein.com).
It is free, reliable, works in any modern browser, you don't have to remmeber IPs and hope they won't change, ...
Or if this is a "for fun project" why not write a php script, open port 80 in your router so you can access you script from outside, possibly dynamically link some domain to your IP (http://www.dyndns.com/). In the script you would just login and then for example type the orders in textfield in some form in your script. Lets just say you want to do some command prompt stuf, so you will basically remotely construst a *.bat file for example. Then the script stores this a fromtheinternets.bat to a folder on your desktop that is being constantly monitored for changes. And when such a change is found you just activate the bat file.
Insecure? Yes (It could be made secureER)
Fun to write? Definitely
PS: I am new here, hope it's not "illegal" to post link to actual services, instead of wiki lists. This is by no means and advertisement, I am just a happy user. :)
I want to create an application for P2P video transmission. In more details, I need the following:
User can switch on a web camera by clicking a button in an application.
Application starts to take images from the web camera and sends them to a certain location (given by a port and IP address).
Application starts to accept images send by another application and display them (images) in a window.
There is also one more thing. I would prefer to have everything in a browser. I know that everything can be done with Flash Player from Adobe (an example is http://chatroulette.com/).
But I would like to know if the same can be done with JavaScripts.
I am sure it the application can be written in Java. But can I use Java to have everything in a Browser.
I'm not sure that webcam access is available in any of the browsers natively yet so you might be out of luck for a pure js solution. I think there's meant to be something added to the spec soon though.
If you want to do it with flash (which is really the best way at present) take a look at red5 which you can run on the server to sit between the clients and deal with the video streaming.
Is it possible to play a sound (.wav or .mp3) in a client's browser using a JSF web app?
I have tried using javax.sound.sampled.SourceDataLine and it worked on Windows, but when I deploy the .war on a Linux host I get this exception:
"javax.sound.sampled.LineUnavailableException: Audio Device Unavailable"
Java code executes on the server to generate web pages that are displayed in the client's browser. If you have JSF web app code using the javax.sound.sampled.SourceDataLine class, the sound will play on the server (if this is even possible...), not in the client's browser.
To play a sound at the client, you'll either have to reference an audio file in the web page as Pascal Thivent has posted, or you'll have to play the sound through a Flash/Silverlight/Java Applet plugin referenced in the page.
Is it possible to play a sound (.wav or .mp3) in a client's browser using a JSF web app?
I should have mentioned that, but this has nothing to do with JSF or any other server-side technology. If you want to play a sound on the client-side, generate the appropriate client-side code, i.e. HTML here.
HTML 5 has an <audio> tag but, until it gets mainstream, see Playing Sounds on a Web Site and How To Play Sound (which does a good job at summarizing the solutions) to learn more on the <embed> tag and the <object> tag.
I have tried using javax.sound.sampled.SourceDataLine and it worked on Windows, but when I deploy the .war on a Linux host I get this exception: "javax.sound.sampled.LineUnavailableException: Audio Device Unavailable"
This exception literally means that the machine where the code runs doesn't have an audio device. I can imagine that it is very reasonable that webservers doesn't have any audio device, this namely doesn't make any sense.
As others have pointed out, you need to play sound at the client machine. You can find here a lot of background information and examples.
Not via JSF but you can use primefaces for an app like that http://www.primefaces.org/showcase/ui/media.jsf
how can I let an SWF file to retrieve values immediately from Java application that does live calculations (Speed is a necessity).
question in other form : how can I
give my website browser immediate data
- that are bean calculated now - as fast as i
can ?
I'm going to assume the calculations are being done in a Java applet in the same browser where the flash is running.
You can call Javascript from within the applet using the following code. This code could then update the values in the flash animation.
import netscape.javascript.JSObject;
JSObject win = JSObject.getWindow(applet);
win.eval("window.alert('Hello from Java')");
If my assumption is incorrect, then where is the Java application running? On the client or server?
If it's on the server then you need Flash remoting. I believe there are a few different Flash remoting techniques. Try searching for java flash remoting. You can make it call the server every 2 seconds or so to get the latest data.
If it's running on the client I doubt you can connect to it from Flash because of security. A signed Java applet could connect anywhere it wants to. You could retrieve the data using it, then push it into Flash using the method described above. Would be a crazy hack though. Can you do the same thing with Flex? (I've never used Flex before).
If the speed is crucial, you would probably want to do it via some kind of socket connection. Usually signed applet or a WebStart Java application is able to open a listening socket. Flash application then would be able to connect to this socket and as a result you will have very fast bidirectional communication.
There are some caveats however.
You should bear in mind that user might get suspicious about weird socket activity on his machine, or it would be just blocked by a firewall - so you'll need to warn user.
In order to be able to connect from Flash to Java, you must dispatch crossdomain policy file from the listening socket (or any other below 1024 - see documentation for details; keywords: crossdomain, policy-file-request, loadPolicyFile). Also your Flash application might need to request such file manually from the Java application.
Couple of useful links on how to get certificate for your Java application: how to get free code signing certificate (Russian), similar but less detailed description in English.
However, if you are able (read: the speed is sufficient) to use Java Applet <-> JavaScript <-> Flash combination I'd advice to take advantage of it.