I'm trying to create server socket on port 554 (rtsp) in Android and i'm getting BindException with 'denied' message:
public RequestListener() throws IOException {
try {
mRtspServerSocket = new ServerSocket(mPort);
start();
} catch (BindException e) {
Log.e(TAG, "Port bind exception");
throw e;
}
}
Are standard ports (or < 1024) unavailable for binding? Do i have to have root permission on the device for that?
PS. I have <uses-permission android:name="android.permission.INTERNET" /> in AndroidManifest.xml
You can't bind to ports <1024.
Either root your phone, modify the firmware, or don't bind to ports
lower than 1024. That's a Linux thing more than an Android thing.
Related
I have a collection of bluetooth earpieces and wanted to be able to connect directly to their AVRCP profile.
The main sticking point is that there is no publicly accessible way to construction an L2CAP socket.
In theory the code below ought to work, but I am getting a permssion denied error.
I do have these in my manifest:
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
The code snippet is here:
private BluetoothSocket createL2CAP(BluetoothDevice bd, UUID uuid) {
BluetoothSocket result = null;
try {
c=BluetoothSocket.class.getDeclaredConstructor(int.class,int.class,boolean.class,boolean.class, BluetoothDevice.class,int.class,ParcelUuid.class);
result=(BluetoothSocket) c.newInstance(BluetoothSocket.TYPE_L2CAP, -1, true, true, bd, -1, new ParcelUuid(uuid));
} catch (NoSuchMethodException e) {
addln("BluetoothSocket: No Such Constructor");
} catch (IllegalAccessException e) {
addln("BluetoothSocket: Illegal access");
} catch (InvocationTargetException e) {
addln("BluetoothSocket: Target exception "+e.getMessage());
} catch (InstantiationException e) {
addln("BluetoothSocket: "+e.getMessage());
}
return result;
}
It's finding the constructor, but throwing the IllegalAccessException.
Has anyone had any luck persuading Android Bluetooth to make any connection type other than RFCOMM? And/or is there a different approach which may have more success?
(PS: addln is just sending messages to a textview so I can see what is happening)
My situation:
I'm trying to create an android app using unity that has a server running, so I can call the service from a PC.
However, when I try to connect to the server I get the error message:
SocketException: No connection could be made because the target machine actively refused it.
System.Net.Sockets.Socket.Connect (System.Net.EndPoint remoteEP, Boolean requireSocketPolicy)
System.Net.Sockets.Socket.Connect (System.Net.EndPoint remoteEP)
System.Net.Sockets.TcpClient.Connect (System.Net.IPEndPoint remote_end_point)
System.Net.Sockets.TcpClient.Connect (System.Net.IPAddress[] ipAddresses, Int32 port)
Doing ping on the IP Address is fine, so the host is reachable, as far as I know android devices don't have firewalls, so my guess it is a problem with the port.
Currently I'm trying to run the service on port 9096, which works if I just run the application in the editor. Is this a valid port for android?
If not, what would be a valid one?
Do you have any other ideas on what the problem could be?
Thank you.
Additional info:
The device is Google Tango and I want to use Thrift to create a server and access the location of the device from a windows coomputer.
========================================================
UPDATE: included code for server and client
public void startServerService()
{
try
{
TangoService.Processor processor = new TangoService.Processor(this);
serverTransport = new TServerSocket(9096);
server = new TThreadPoolServer(processor, serverTransport);
Debug.Log("Starting the server...");
server.Serve();
}
catch (UnityException e)
{
Debug.Log(e);
}
}
void startClient()
{
try{
TTransport transport = new TSocket(ipAddress, 9096);
transport.Open ();
TProtocol protocol = new TBinaryProtocol(transport);
client=new TangoService.Client(protocol);
}
catch(UnityException e)
{
Debug.Log(e);
}
}
I am trying to connect a simple android client to a simple java server on another computer running on the same wi-fi network, i was able to connect with a java code(non android) on eclipse, and the server works just fine, but when i take the same code and put in my android app (android studio), it throws an IOException.
As of right now my protocol just returns a string "yay" and i just want to display it in a View.
My code:
private void createCom2(TextView showResult){
Socket pazeSocket = null;
PrintWriter pw = null;
BufferedReader br = null;
String ip = "10.0.0.4";
try {
pazeSocket = new Socket(ip, 4444);
pw = new PrintWriter(pazeSocket.getOutputStream());
br = new BufferedReader(new InputStreamReader(pazeSocket.getInputStream()));
} catch (UnknownHostException e) {
Toast.makeText(this,"Don't know about host: " + ip , Toast.LENGTH_SHORT).show();
} catch (IOException e) {
Toast.makeText(this,"Couldn't get I/O for the connection to: " + ip , Toast.LENGTH_SHORT).show();
}
}
Thanks.
You need Internet permission for your app. Add this line to your manifest file:
<uses-permission android:name="android.permission.INTERNET"/>
and read more abut permissions here, if you like:
http://developer.android.com/guide/topics/manifest/manifest-intro.html
I want to code an Android app, which will connect to a network printer with a specific IP address, and then make a printing.
For printing I know that I need to write my own Postscript for specific files types, and connecting to a network is not a problem over WIFI.
How to connect to the network printer?
Any device connected to a network will communicate via their IP and Ports / sockets. The simplest way to connect via telnet or socket and write the data to their socket buffers.
try
{
Socket sock = new Socket("192.168.1.222", 9100);
PrintWriter oStream = new PrintWriter(sock.getOutputStream());
oStream.println("HI,test from Android Device");
oStream.println("\n\n\n");
oStream.close();
sock.close();
}
catch (UnknownHostException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
You might be able to use lpdspooler, that is, if the printer supports LPR/LPD. If you can give some more details about the environment (printer, etc), I might be able to give more information.
Just Add This Code After oncreate Method
if (android.os.Build.VERSION.SDK_INT > 9) {
StrictMode.ThreadPolicy policy =
new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
}
Star has an Android SDK which has port discovery. It'll find any of their wifi receipt printers on your network. http://starmicronics.com/support/SDKDocumentation.aspx
Try to use PrintManager: https://developer.android.com/training/printing/custom-docs
private void doPrint() {
// Get a PrintManager instance
PrintManager printManager = (PrintManager) getActivity()
.getSystemService(Context.PRINT_SERVICE);
// Set job name, which will be displayed in the print queue
String jobName = getActivity().getString(R.string.app_name) + " Document";
// Start a print job, passing in a PrintDocumentAdapter implementation
// to handle the generation of a print document
printManager.print(jobName, new MyPrintDocumentAdapter(getActivity()),
null); //
}
My solution. I used Epson TM series. I think the port is 9100 for default.
In Manifest add:
<uses-permission android:name="android.permission.INTERNET"/>
in the activity use a Thread otherwise u you can the android.os.NetworkOnMainThreadException error.
Thread thread = new Thread(new Runnable() {
#Override
public void run() {
try {
Socket sock = new Socket("192.168.1.168", 9100);
PrintWriter oStream = new PrintWriter(sock.getOutputStream());
oStream.println("Hi, test from Android Device");
oStream.println("\n");
oStream.close();
sock.close();
} catch (UnknownHostException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
}});
If not enough, add in manifest these:
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
Well, you cant connect any devices directly as you will need the driver installed. there are 3rd party apps like Google Cloud print that works seamlessly with Android though.
I've sucessfully compiled jNetPcap as a shared library for Android. I have made a simple application using this code: http://jnetpcap.com/examples/classic to test the API.
The problem is that when I call the method findAllDevs and exception is raised with this message: "Can't read list of devices, error issocket: Permission denied"
I cannot understand the reason, since I have made a call in the first part of my program so as to get root permissions for my application and I test my application to a rooted phone. When I run the application, a pop up is raised with this message:"SnifferApp has been granted Superuser permissions" and then the exception occurs.
Any ideas?
Here is a piece of my code:
Process p = Runtime.getRuntime().exec("su");
/*try {
Thread.sleep(10000);
} catch (InterruptedException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} // do nothing for 1000 miliseconds (1 second)
*/
try {
System.loadLibrary(JNETPCAP_LIBRARY_NAME);
}
catch (UnsatisfiedLinkError e) {
System.out.println("Native code library failed to load.\n" + e);
}
/***************************************************************************
* First get a list of devices on this system
**************************************************************************/
int r = Pcap.findAllDevs(alldevs, errbuf);
r = Pcap.findAllDevs(alldevs, errbuf);
if (r == Pcap.NOT_OK || alldevs.isEmpty()) {
tv.append("Can't read list of devices, error is" + errbuf
.toString());
setContentView(tv);
return;
}
As far as I understand, you're creating a new process and getting superuser permission, but your app doesn't have them.
Try adding this permission in your manifest file:
<uses-permission android:name="android.permission.INTERNET" />
as I guess findAllDevs is going to open the network devices on the phone.