Please excuse my noobishness as I am teaching myself Java and don't know a lot.
I'm trying to make a multiplayer game that runs from Java applets, I have a server-side program working that will accept strings of text, but all my attempts to find code for applets have failed.
My best attempt looks like it works but I think fails to connect to the server, any ideas why? (localIP is my correct IP and works fine in other tests)
public void init()
{
try
{
socket = new Socket(localIP, 5555);
inStream = new DataInputStream(socket.getInputStream());
outStream = new PrintStream(socket.getOutputStream());
}
catch(Exception e)
{
never reached
}
}
I don't mind scrapping this if someone can tell me a better way to do it or any way at all.
a java applet can only connect to the server from which it was downloaded. if you are not loading the applet from localIP, then you will not be able to connect to it.
you may be able to get around this restriction by signing the applet.
Given that you are not using the Http Protocol, One assumes that the applet is loaded from another port other than 5555. If this is the case, the applet needs to be signed in order to do this functionality.
Related
So, this is a rather unusual question, and I can't find anything else anywhere which has been helpful on how to do this, or if its even possible to do so.
I'm working on a game server wrote in java, and I'm trying to get the users default web browser to open to a specific link, when a command is typed into the chat box and sent to the server.
The current Issue I have is, when a user issues the command, it opens the browser on the host system, and not the players system.
I haven't been able to try any other methods, as I am unable to find any information regarding my specific situation!
#CommandHandlerMethod(accessLevel = EAccessLevel.USER)
public static Object[] vote(final Player player, final String... params) {
try {
Desktop desktop = java.awt.Desktop.getDesktop();
URI oURL = new URI("www.example.com");
desktop.browse(oURL);
} catch (Exception e) {
e.printStackTrace();
}
return AbstractCommandHandler.getAcceptResult("");
}
What I was hoping for via this code, was to open the web browser on the players system to allow them to view a specific webpage, but this has not been the case, and opens it on the server host system.
Does the native code of the VideoView give access to the received packets of the video before or after decoding it? I need to access these packets in order to transmit them to another device. The initial solution is to modify the Android native code. Other possible solutions that I found are to use GStreamer or FFmpeg libraries.
I need bit guidance in order to achieve that goal.
Assume the phone is rooted.
Short answer is no, not that I know of.
Long answer is that you haven't given enough detail. What data exactly do you need access to? Are you writing an application, or modifying your OS to do this to other applications?
The code that actually fetches a remote video is in MediaPlayer and is native. See the following method in MediaPlayer:
private void setDataSource(/* snip */) throws /* snip */ {
/* snip */
else if (scheme != null) {
// handle non-file sources
nativeSetDataSource(
MediaHTTPService.createHttpServiceBinderIfNecessary(path),
path,
keys,
values);
return;
}
/* snip */
Unfortunately for you, almost all of the relevant MediaPlayer code is native, and if not, it is private (so subclassing will not work here).
However, depending on what you need to do, you could possibly override VideoView method setVideoURI(Uri, Map<String, String>), which is public. Here you can grab the URI and then proxy it through your own web service, or something. This isn't quite what you were asking, though.
Or, you could possibly look into modifying the Surface that is drawn to by MediaPlayer. Most of the relevant code is still native though.
The final possibility that I'll mention (there are probably hundreds of possible approaches) would be to modify the MediaHTTPService class. This appears to be used by MediaPlayer, but I can't be sure because if it's used, it's used in native code.
This answer recommends finding the native code at androidxref.com
Edit:
As requested, here is a little more detail about what the "proxy server" solution might look like. I don't know the implementation details on Android.
Basically, when you get a URL to play in the VideoView, you pass it to your own server instead. Something like startProxyServer(videoUrl). This starts a server, which downloads and then re-hosts the video. To get this working locally, start a webserver listening on localhost. The server just downloads the video at videoUrl, saves it locally, and then hosts it at localhost:port/?video=${videoUrl}.
So in very high-level pseudo-code the server could look like.
public void startProxyServer(String videoUrl) {
int PORT = 28641; // random port
File f = downloadFile(videoUrl);
saveFile(f, '/path/to/server/storage');
startWebServer('localhost', PORT);
}
So now you give localhost:port/?video=${videoUrl} as url to the videoView instead. Also, now other videoView instances can download from that same localhost url.
To make it work with other phones, your server of course couldn't run on localhost.
Of course I've not implemented this, but it's just one solution I can think of.
I am using the Restlet Framework, but now I want to change to a proper server instead of using localhost.
I have already added my php files (they access the java files using the rest_server URL) to the server's folder and my java files as well, but I am not sure how to change the code so it identifies where the new location of the files is.
Here is the code from IdentiscopeServer (constructor empty):
public static void main(String[] args) throws Exception {
//setsup our security manager
if (System.getSecurityManager() == null){
System.setSecurityManager(new SecurityManager());
}
identiscopeServerApp = new IdentiscopeServerApplication();
IdentiscopeServer server = new IdentiscopeServer();
server.getServers().add(Protocol.HTTP,8888);
server.getDefaultHost().attach("", identiscopeServerApp);
server.start();
}
I guess that the correct line to change is the one with "Protocol.HTTP, 8888". If the address of my new server is http://devweb2013.co.uk/research/Identiscope, how exactly do I set this up? Is there anything else necessary for it to work apart from just moving the files to a folder in the server?
The IdensticopeServerApplication is the following:
public class IdentiscopeServerApplication extends Application {
public IdentiscopeServerApplication() {
}
public Restlet createInboundRoot() {
Router router = new Router(getContext());
//attaches the /tweet path to the TweetRest class
router.attach("/collectionPublic", CollectionPublicREST.class);
router.attach("/collectionPrivate", CollectionPrivateREST.class);
router.attach("/analysis", AnalysisREST.class);
return router;
}
}
Thank you in advance, it is my first time using this Framework.
If I understand you correctly, you just want to run your main() method as the server, correct? In this case, the code for main() needs to be in a location that -- when running -- can provide the service at http://devweb2013.co.uk/research/Identiscope. Since you haven't stated what kind of server you are putting the code, I can't say where the best place to put the code would be. I assume you have superuser privileges on your deployment server, since the URL you provided implies port 80 will be serving your Identiscope web service (port 80 is a privileged port on most OS's). So as an answer, I can only provide general information.
On your deployment server, port 80 must be free (i.e. nothing else should be acting as a web server on port 80 on that machine) and the IdentiscopeApplication must be running on port 80. To do that, you need only change the line:
server.getServers().add(Protocol.HTTP,8888);
to:
server.getServers().add(Protocol.HTTP, 80);
then run the application as a user that is allowed to start servers on port 80 (preferably NOT the superuser). If you haven't already, you will need to get Java running on your deployment server and make sure all Restlet libraries are in the classpath where you plan to run your application.
If I understand what you are trying to do, then this should do the trick.
I know that by using AT commands we can control the handset.As example unlocking screen we can give a specific AT command or moving right to the menu or left or bottom or up we can give specific AT commands. What all are the AT commands for doing this kind of control.
Thank you.
From what I understand, the AT commands are more used for phone-type functions (making calls, or sending SMS, etc), rather than menu navigation, etc.
I'm not entirely sure if that was your end-goal after menu navigation, but you can find more details here: http://en.wikipedia.org/wiki/Hayes_command_set (the original +AT command set)
If you wanted to send SMS from a handset connected to your computer you might want to take a peek at this page: http://www.developershome.com/sms/atCommandsIntro.asp
If you wanted more control when performing functions, like sending SMS, etc, you might want to investigate "PDU Mode."
It is entirely possible that some handset manufacturers may have implemented additional +AT commands to allow other functions to be performed, so you might do better by specifically searching for the commands related to the handset you are using.
(Of course, if you're having issues connecting to the handset hardware itself, you need to ensure you have either the javax.comm extension or some favoured Java USB API installed)
If post doesn't help, perhaps you could provide more details in your question? (eg. what you are ultimately trying to do, if you think it would help)
List of AT commands
sample java code to use AT command
public void servicesDiscovered(int transID, ServiceRecord serviceRecord[])
{
String url = serviceRecord[0].getConnectionURL(1, false);
try
{
//ClientSession conn= (ClientSession)Connector.open(url);
StreamConnection meineVerbindung = (StreamConnection) Connector.open(url);
if(conn== null)
System.out.println("Kann Service URL nicht oeffnen\n");
else
{
OutputStream out = conn.openOutputStream();
InputStream in = conn.openInputStream();
String message = "AT+CGMI\r\n";
// send AT-command
System.out.println("send AT Comand request: "+message);
out.write(message.getBytes());
out.flush();
out.close();
byte buffer[] = new byte[10000];
// read the response from mobile phone
in.read(buffer);
System.out.println("AT Comand response: "+buffer.toString());}
}
catch(IOException e)
{
System.out.println("Service Error(3): "+e.getMessage());
}
}
I'm trying to test my code that reads from a USB port (COM25 when the device is connected) that is created when a device is connected to my computer and to a boat. I cannot power the USB device when not on the boat so testing is difficult. Can someone let me know how to simulate a COM port and write data to it so my test program is able to connect to that simulated COM port and read that data?
I'm reading this from a Java program but the simulation doesn't need to be in Java or any specific language. Just a program that will simulate the COM port and allow me to connect to it. I downloaded a COM port emulator from AGG Software and it appears that it's writing to what I deem COM25 but I'm not able to connect to it from my Java test.
The general answer for this kind of problem is to wrap the code that talks to the COM port in a class that implements an interface. If you do this as a Facade (pattern) then you can also make the COM methods you call sensible from your end.
The interface can then be mocked or faked for the test. (There is a great article on test objects, but I haven't been able to find it yet.) One advantage here is that you can create a fake version that throws exceptions or otherwise does things that are possible for the port to do but hard to get it to do in practice.
Where I work, we solved a similar issue by having our emulator not spoof a COM port at all. Here's how you can do it:
Define an interface for talking with your COM port, something like IUsbCommService
Implement your real COM-communcation service, using the standard Java Comm API
For your emulator, simply kick of a thread that spits out the same sort of data you can expect from your USB device at regular intervals.
Use your IOC framework of choice (e.g., Spring) to wire up either the emulator or the real service.
As long as you hide your implementation logic appropriately, and as long as you code to your interface, your service-consumer code won't care whether it's talking to the real USB device or to the emulator.
For example:
import yourpackage.InaccessibleDeviceException;
import yourpackage.NoDataAvailableException;
public interface IUsbProviderService {
public void initDevice() throws InaccessibleDeviceException;
public UsbData getUsbData()
throws InaccessibleDeviceException, NoDataAvailableException;
}
// The real service
import javax.comm.SerialPort; //....and the rest of the java comm API
public class UsbService implements IUsbProviderService {
.
.
.
}
// The emulator
public class UsbServiceEmulator implements IUsbProviderService {
private Thread listenerThread;
private static final Long WAITTIMEMS = 10L;
private String usbData;
public UsbServiceEmulator(long maxWaitTime) throws InaccessibleDeviceException{
initialize();
boolean success = false;
long slept = 0;
while (!success && slept < maxWaitTime) {
Thread.sleep(WAITTIMEMS);
slept += WAITTIMEMS;
}
}
private void initialize() throws InaccessibleDeviceException{
listenerThread = new Thread();
listenerThread.start();
}
private class UsbRunner implements Runnable {
private String[] lines = {"Data line 1", "Data line 2", "Data line 3"};
public void run() {
int line = 0;
while(true) {
serialEvent(lines[line]);
if(line == 3) {
line = 0;
} else {
line++;
}
try {
Thread.sleep(200);
} catch (InterruptedException e) {
//handle the error
}
}
private void serialEvent(String line) {
if(/*you have detected you have enough data */) {
synchronized(this) {
usbData = parser.getUsbData();
}
}
}
}
Hope this helps!
Thanks to all the answers so far! Here's what I ended up doing as a result of recommendations from someone at work.
Downloaded the COM Port Data Emulator (CPDE) from AGG Software
Downloaded the Virtual Serial Port Driver (VSPD) from Eltima Software
(I just randomly picked a free data emulator and virtual serial port package. There are plenty of alternatives out there)
Using VSPD, created virtual serial ports 24 and 25 and connected them via a virtual null modem cable. This effectively creates a write port at 24 and a read port at 25.
Ran the CPDE, connected to 24 and started writing my test data.
Ran my test program, connected to 25 and was able to read the test data from it
There are plenty of relevant answers in this section. But as for me, I personally use Virtual Serial Port Driver, which works perfect for me. But I must admit that there are plenty alternatives when it comes to creating virtual ports: freevirtualserialports.com; comOcom to name a few. But I haven't got a chance to use them, so my recommendation for solving this problem is Virtual Serial Port Driver.
I recommend fabulatech's virtual modem.
Get it at http://www.virtual-modem.com
You might also want to get a COM port monitor for your tests - You can find it at
http://www.serial-port-monitor.com
Good luck with the boat! :)
I use com0com and it works great for what I need.
In addition all others, I would like to added this nice, free emulator https://sites.google.com/site/terminalbpp/ I do use. I do also use AGG Com port data emulator.