How to achieve service discovery like "Printer Discover" on android?

Question

Hi, I would like to know about the 'service discovery' mechanisms supported by android - particularly, Printer Discovery.

Does android provide such a discovery option? example : support for snmp broadcast?

I tried out an application "PrinterShare" link : http://www.printeranywhere.com/mobile.sdf where Printer Discovery is achieved through ipp.

Any help is appreciated.

Answer 1

Does android provide such a discovery option?

Not that I am aware of, sorry.

Answer 2

This code snippet works fine on J2SE. However, on the Android emulator, I get a 'Time Out Exception' with response = 'null'

`DatagramSocket clientSocket = new DatagramSocket(8888); clientSocket.setSoTimeout(20000);

/**
 * SSDP is a text-based protocol based on the Hypertext Transfer Protocol (RFC 2616). 
 * However, it uses the User Datagram Protocol (UDP) as underlying transport protocol.
 *  Services are announced by the hosting system with multicast addressing to a 
 *  specifically designated IP multicast address at port number 1900. In IPv4, 
 *  the multicast address is 239.255.255.250.
 */
                        //getByName(host)   //host  the hostName to be resolved to an address or null.
InetAddress group = InetAddress.getByName("239.255.255.250");

//host can be null which means that an address of the loopback interface is returned.
if(group == null){
    Log.d("Discovery","getByName(): returns address of loopback interface.");
}
byte[] sendData;
byte[] receiveData = new byte[128];

String sentence = "M-SEARCH * HTTP/1.1\r\n"
    + "HOST: 239.255.255.250:1900\r\n"
    + "MAN: \"ssdp:discover\"\r\n"
    + "MX: 10\r\n"
    + "ST: ssdp:all\r\n"
    + "\r\n";

sendData = sentence.getBytes();
//public DatagramPacket (byte[] data, int length, InetAddress host, int port) 
DatagramPacket sendPacket = new DatagramPacket(sendData, sendData.length, group, 1900);

try {
    clientSocket.send(sendPacket);
} catch (Exception e) {
    e.getMessage();
    e.printStackTrace();
}
Log.d("Discovery","sent packet...");
while( true)
{
    DatagramPacket receivePacket = new DatagramPacket(receiveData, receiveData.length);
    try
    {
        boolean isc = clientSocket.isConnected();
        clientSocket.receive(receivePacket);
    }
    catch ( Exception Ex)
    {
        Log.d("Discovery","Time out Exception");
    }
    if (receivePacket.getAddress() == null)
    {
        Log.d("Discovery","receivePacket.getAddress() == null");
        break;
    }
    Log.d("Discovery","Senders Address : " + receivePacket.getAddress().getHostAddress());
    String controllerResponse = new String(receivePacket.getData());       
} //end of while()
clientSocket.close(); `