import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;

public class udp_test
{
public static void main(String[] args) throws IOException
{
InetAddress IP = InetAddress.getByName("alamatipgwsensor");
int port = portnumbergwsensor;

try
{
byte [] datapacket = new byte [128];

DatagramSocket ds = new DatagramSocket();
DatagramPacket dp = new DatagramPacket(datapacket, datapacket.length);

ds.setSoTimeout(100);
ds.connect(IP, port);
ds.send(dp);
ds.isConnected();

ds.receive(dp);
ds.close();

String strRecv = new String(dp.getData(), 0, dp.getLength()) + " from "
+ dp.getAddress().getHostAddress() + " port " + dp.getPort();

System.out.println(strRecv);
}
catch (SocketException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}


}
}