I want to create a multi-cllient client-server program in which the server has separate windows to display all clients screens, to monitor what's going on on their computers. How will i do it?
i want to know how will i display the screen on the server i am using a GUI interface.
You'll set out your requirements, come up with an initial design, flesh out the design, begin implementing it, and then refine the design, continue implementing, test, and debug until you have a satisfactory implementation. If you run into trouble or have specific questions, you can ask more questions.
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Quite simply as the title states, is it possible for Java to read what is happening in a web-browser based Flash game?
For Example: Could I make a Java program which could play FarmVille for me by reading what is going on currently and make decisions based on a pre-determined set of actions?
FarmVille doesn't publish any sort of API, and you won't be able to access the RAM allocated to the Flash player (to my knowledge), so your only real course of action is to analyze the screen and automate input. In other words, there's no prewritten farmville.getUnplowedCells() to use, but you can write a program that takes screenshots, analyzes them to find the unplowed cells, and then generates the mouse/keyboard input that would make your character plow his unplowed cells. The Robot class can be used for this sort of programming.
This would be very time consuming and probably not worth the effort. Also as a side effect this would essentially "take control" of your mouse and keyboard and prevent you from using your computer normally. However this problem can be mitigated by running the program in a virtual machine.
No, there is no implementation for a Java-Flash bridge that allows anything more direct than IPC. Your best bet is decompilation (which would probably require deobfuscation) of the swf and interaction through common IPC mechanisms.
You could also tackle this using a different approach by recognizing elements on the screen by their pixel colors, for that you could use the Java Robot API which provides you with access to the keyboard, mouse and video. Since FarmVille is a 2D game, recognizing elements on the screen should be fairly straightforward -- performing image comparison, or partial image comparison (just the image's borders or a representative part) to increase the speed.
Aside, cheating in online games is not a nice thing to do and you can probably find activities that are more productive given you are smart enough to make software that works.
If you goal is to make a bot for FarmVille, then you're heading a wrong way. Keep in mind: it's ONLINE game. So, you don't have to read flash client's state, it'll be much more better, to read incoming packets, you don't have to simulate mouse/keyboard events in swf - just create correct packets, discribing your in-game actions. So I recomend you act like this:
1) Write a sniffer in Java (it's quite easy, because you have to write a simple one, not an ultimate tool, like Wireshark).
2) Use request's analytic (such as Firefox's Firebug) to catch some packets from your game. Reading them, you can retrieve all info, what you need: packets headers, game actions encoding, etc.
3) Code logic in your Java program: read incoming game packets and execute actions, sending requests.
4) Set user-agent options of your connection object similar to a popular browser (if you refuse doing that, game server may ignore your requests).
That's all. Remember: a game bot isn't an image recognizer, it's just another game client, with another GUI and logic.
P.S. If I misunderstood you, and your goal is to create a webpage with flash and applet, which comunicate with each other, you have to use JavaScript as a mediator between them. Flash calls JS using ExternalInterface.call, JS calls applet and vice versa.
I am trying to make an online application that will be like an online exam, But I want to ensure that no user can browse internet during the test. Is it possible ANYHOW?
I am thinking about a fullscreen application that don't minimize. But that cannot eliminate the chances that user alt-tabs other window :(
Any direction is highly appreciated.
Technology is no bar. Having said that, the students will be taking the test from home.
I think this would be better solved on the network layer in your school router.
Block IP access to everything except the online test for this class room while test is being taken..
Technology is no bar. Having said that, the students will be taking
the test from home.
Do understand the spirit of laws 1,2,3 of the 10 Immutable Laws of Security:
Law #1: If a bad guy can persuade you to run his program on your
computer, it's not your computer anymore
Law #2: If a bad guy can
alter the operating system on your computer, it's not your computer
anymore
Law #3: If a bad guy has unrestricted physical access to your
computer, it's not your computer anymore
The only computers that conform to your will (in your case, you want the PCs to disallow browsing) are those for which you have complete control of the hardware and software.
You can fool only the less sophisticated users. If your users are inclined, they can easily learn to bust it. From the DRM fiasco and certain personal anecdotes from school and college, its well proven that the users can be one step ahead and trying to close the gap is a black hole for money and effort.
Also the kids are at home. They can always use other devices or means. You can make a page with javascript that can prevent it from going out of focus, but a 10 year old can learn to open another window. Make a fullscreen desktop app that checks if the mouse is "inside" , a 16 year old can run it on a virtual machine or screen session. Yes, I was that smart at that age and kids are getting more smarter than you or me.
Also, automated systems to detect wrongdoing are likely to take innocent victims and cause pain and resentment. Internet filters that trip on "Steve Jobs death" and "new c# jobs" for the same reason are an annoyance. Payment processors and site advertising with automated fraud detection algorithms and customer care that stonewalls have made people broke.
You could also set a system (IE) proxy, and write a small Proxy Server to intercept any outbound requests and return nothing
Writing such Proxy is trivial...
If you are on Windows, you could write a batch file to start your program and use the REG command to modify the registry key(s)
Processing has Android support and it seems to be pretty awesome from my 10 minutes of playing with it. But I would like to make a regular (nongraphics) application like a twitter feed reader or something. So is there something like Processing that can do regular apps? Besides Titanium...
Basically I am looking for anything that will make coding for android easier, processing was so easy to get working that I was very happy with it, but it is for graphics only. Titanium didn't give me the same wow factor and it isn't open so that kind of takes away from it. What other tools are out there?
I'm going to give you the answer you are looking for and some advice.
Processing can do ANY of the things you are thinking about doing. If you want textboxes etc, you can use the Control P5 library. It's great. If you are an expert at Processing and just want to port over your Processing code to android, Processing for android is great.
But that's not what you want to do. You want to write an application. And you want to write it on Android. There are frameworks designed to give you a leg up in writing cross-platform mobile apps, but nothing is going to make writing an android application easier than learning Java and learning how the android stack works. It's actually really well designed and easy to follow once you start grokking "intents" and "bundles".
At the end of the day, you might even want to scale back a little further. Are you trying to write an application that needs to be used without internet access or that uses super special phone APIs? If you aren't, maybe you should try just writing your app as an html5 css3 website.
You can do plenty of input based stuff with processing. The original mouse events work as specified, except pass touches, but you can also access things like pressure and multiple fingers down. The hardware keys are also supported.
When considering a platform for a game, I've decided on multi-platform (Win/Lin/Mac) but can't make up my mind as far as browser vs. desktop. As I'm not all too far in development, and now having second thoughts, I'd like your opinion!
Browser-based games using Java applets:
market penetration is reasonably high (for version 6, it's somewhere around 60% I believe?)
using JOGL, 3D performance/quality is decent; certainly good enough to render the crappy 3D graphics that I make
there's the (small?) possibility of porting something to Android
great for an audience of gamers who switch computers often; can sit down at any computer, load a webpage and play it
also great for casual gamers or less knowledgeable gamers who are quite happy with playing games in a browser but don't want to install more things to their computer
written in a high-level language which I am more familiar with than C++ - but at the same time, I would like to improve my skills with C++ as it is probably where I am headed in the game industry once I get out of school...
easier update process: reload the page.
Desktop games using good ol' C++ and OpenGL
100% market penetration, assuming complete cross-platform; however, that number reduces when you consider how many people will go through downloading and installing an executable compared to just browsing to a webpage and hitting "yes" to a security warning.
more trouble to maintain the cross-platform; but again, for learning purposes I would embrace the challenge and the knowledge I would gain
better performance all around
true full screen, whereas browser games often struggle with smooth full screen graphics (especially on Linux, in my experience)
can take advantage of distribution platforms such as Steam
more likely to be considered a "real" game, whereas browser and Java games are often dismissed as not being real games and therefore not played by "hardcore gamers"
installer can be large; don't have to worry so much about download times
Is there a way to have the best of both worlds? I love Java applets, but I also really like the reasons to write a desktop game. I don't want to constantly port everything between a Java applet project and a C++ project; that would be twice the work!
Unity chose to write their own web player plugin. I don't like this, because I am one of the people that will not install their web player for anything, and I don't see myself being able to convince my audience to install a browser plugin.
What are my options? Are there other examples out there besides Unity, of games that have browser and desktop versions? Did I leave out anything in the pro/con lists above?
I'd suggest writing a game first.
It's easy to get caught up in how to make the best game ever,which can run on anything from an abacus to SkyNet, but the reality is that you're going to have plenty of challenges ahead of you just finishing a game that runs on your own PC.
Write a game first, for one platform (whether that platform is "Windows native with DirectX", or "Java applet" or even "pure AJAX in a browser"). If you can do that, then you can start thinking about how to port it to other platforms. But trying to do everything is a sure way to end up achieving nothing.
Or to put it another way:
I've decided on multi-platform (Win/Lin/Mac)
so you've actually decided nothing. Decide on a platform to develop on. Then make the game. Then make it work on other platforms.
Don't worry so much about what your "audience" will find acceptable. If your game is fun, then yes, people will happily install Unity. Just like they'll install your game if it's not browser-based. But the important point is not "what do I have to install to play it", but rather "is it worth it". Your focus should be on making a game that is worth the installation.
And unless you're planning to sell 20 million copies of the game and live off it, your "audience" doesn't really matter that much, does it? What matters is putting the game out there so those who are interested can try it.
But a single-platform game is a lot better than an unfinished cross-platform nothing.
A game that requires me to install Unity is a lot better than something that takes you an additional 3 years to develop because you insisted on reinventing the wheel.
Yes you can have the best of both worlds.
It's perfectly possible to write a Java application that will run in both an applet (for your online users) while also running as a standalone application in downloaded form.
The key technologies are:
JNLP
JOGL for the graphics, which also has some good demos
I'm not so familiar with it but I think jMonkeyEngine looks very promising if you want more of a full-featured game engine
If it's any use, an old game I wrote called Tyrant supported running both as an applet and as a standalone downloaded .jar file, all the source is open if you want to look at it. This used simple AWT rather than 3D graphics.
And finally here's another example of converting an applet into an application with a pretty minimal amount of code.
If you really want that kind of penetration then I suggest HTML 5 + javascript depending on the performance you need.
First of all you start with the wrong question. Your decision for a technology should be driven by the concept behind the game. It seems that you are sure about the idea to write a game - so ask your self what the requirements for the game are. This will lead you to your technologie. If it doesn't get an idea of "what" you want to do.
To your Pro's and Con's:
Don't focus on things you will never need or be able to use. Thinking about the steam platform isn't interesting for a hobby developer. Also android isn't interesting if you are not really want to ship your application for android. This Pro's will actually never be a pro in reality.
To sum it up: Let this decision be driven by your idea, not the technology itself. If you have a clear idea of what you want to do you will get your answer.
(And btw.:
Think about what browsergames imply. Behind a Browsergame there is a huge service-area, only for keeping the game running. Companys working in such areas are basically service-providers.)
You might want to look into Google's Native Client, which allows you to write your application in C or C++ (or anything else that compiles to native code, really). A new feature coming to the SDK is LLVM support, which will (hopefully) allow NaCl software to target any platform that Google's Chrome browser runs on (or any browser that the NaCl plugin works with - currently x86 and ARM are supported, IIRC).
You mentioned Android in your question - have you thought about developing the game purely for Android?
In effect you get the best of both worlds, easy to maintain, easy to release new versions, easy to monetize and get some small income and you don't have write your own installer or update mechanisms either.
Yes. You can make something that will work in both. Basically, make your program work inside a JPanel. The applet can display the JPanel, and the desktop version is just a window with your JPanel in it.
You could also have a full Swing (or whatever) GUI, which the applet launches in a new window when they click the little "start" button you'd have on your applet.
There are a few other differences you'll have to take into account, like possibly loading resources, but I've done it before for simple games I've made.
I don't think you can really compare the two:
In my opinion:
Applet, flash and other browser based games are typically small "toy" games either written for free or supplemented with advertising. For examples, check out the Addicting Games website.
C++ games are more likely to be heavyweight studio-written games relying on dedicated physics engines, graphics engines, etc (particularly true of games distributed on Steam I would have thought). The learning curve is likely to be much steeper, as C++ is inherently a more difficult language than Java / Flash.
If you're unfamiliar with C++ my advice would be to steer towards Java with JOGL. That way you can scale the Open GL learning curve before having to tackle C++.
EDIT
To address the other section of your question regarding implementing a game in both browser and desktop form, you could consider implementing the game in Java and deploying an applet and standalone version, whereby the standalone version can take advantage of Java's full-screen exclusive mode API. You could base both applications on the same codebase. You could also consider shrinking the applet's footprint size by retaining data files (e.g. game levels) on the server-side and retrieving them dynamically when required.
While WebSense won't let me browse directly to the site, for obvious reasons, the first thing that came to mind when reading this question is a game like Wurm Online. It's written in Java with JOGL, implements content streaming and local caches, and seems to have touched on a lot of the points you're interested in. It's a desktop Java application rather than being truly "in-browser" but I think you could still learn quite a bit from its implementation.
The in-browser game is always in peril of having its window closed or refreshed, causing it to abruptly lose state unless everything is being kept server-side. This means you either have very simple games that can maintain synchronization using a call/answer model (such as the myriad of Facebook "Mob Wars" text-based games) or risk an inadvertent bump of F5 catapulting someone back to their last "saved game."
I'm not sure that refusing to use a plugin because you personally don't like it is a sensible choice. This option lets you write you app installable as a desktop app, or a browser plugin (with not much extra work) and you still get to write it in C++/GL. You said you don't think your users will install plugins... why not? If they will install an application then why not a plugin which basically boils down to the same thing?
You could look at Flash too, which is gathering some 3D functionality and can run in-browser or as an AIR dektop app. But then users would need a Flash plugin, which you presumably don't have either.
I am looking to create a video training program which records videos - via webcam, user screen capture and captures sound. Now the main problem is that I need a cross-platform (mac and windows) solutions.
I know its possible to use flash to record webcam + audio. But its not possible to record the user's screen via flash.
So am wonder if I should use Java (which i believe will work on mac & windows). I do not want to develop to separate versions because of the cost involved in developing two versions.
Please guide me as I am new to this.
Thank you.
UPDATE
Hello again,
I had a look at the following site: www.screencast-o-matic.com or www.screentoaster.com. I see that they have developed a java applet which helps interact with Windows/Mac to record the screen.
I am wondering how to go about developing something like that and integrating it with Flash (for webcam and audio recording).
Is this a better idea?
This is not an answer to your question, but I strongly recommend against using video for educational programmes. Our company delivers university courses on-line, and we long ago learned that video feeds are only effective under particular scenarios. In general, a talking head is a waste of bandwidth. You're much better off to put together a well designed powerpoint presentation, record a voice-over (and edit it!) and then assemble the whole thing as a flash presentation. This is a non-trivial amount of work, but it provides a much more interesting product for the student.
When to use video:
1) When you are demonstrating something dynamic - Mechanics or Chemistry for example.
2) When you are acting out a scenario or case as an illustration -- For example, threat de-escalation techniques for high school teachers.
When you solve the screen recording problem, seriously consider whether you need full motion or if you can get away with stills. Often the motion is distracting, and a still with good voice over can be more effective. (Hint: Replace mouse pointers with something HUGE before recording -- Like Fox did with hockey pucks)
Try CamStudio. I don't know, if it works on Mac, but on windows, it's the best solution I know. It's open source, so you can use it's source code, if you want to :)
If you're looking to build an application that does all of the recording and screen capture itself, then you might consider using Adobe AIR (essentially, Flash running on the desktop) in combination with Merapi. Merapi is essentially a bridge between Adobe AIR and Java. So for example, for your project, you might use Java to handle the lower-level (but still cross-platform) stuff you can't do natively in AIR, and use Merapi to wire the Java application to your AIR UI.
This is by no means a simple project. Lets get that said and out the way. There are open source (and cross-platform) options for each element, but nothing (I know of) that will do everything for you.
I think the "cleanest" option would be to use Flash for webcam and audio, as you said, and run a VNC server to send the screen video... The only closed-platform code will be the VNC launching code. That should be pretty simple to maintain!
That raises a problem because most people are behind NAT firewalls these days. Setting up port forwarding is a pain in the behind. I've used an app called Gitso before which allows people to connect to me and send their desktop to my screen (for tech support). Its VNC-based and all it really does is add another layer on top of the VNC connection so rather than me connecting to them, they connect to me. That makes the whole business of port forwarding a non-issue.
And once you've recorded everything, there's the final issue of syncing it all back together... Might not be so hard.
Well, Camtasia provides the solution to get your problem done. It can record the onscreen activity and also the webcam video and put them in the same player template. Another screen recorder DemoCreator can publish the screen recording as Flash movie, but can not record the webcam.