How to ping an IP address
InetAddress.isReachable()
according to javadoc:
".. A typical implementation will use ICMP ECHO REQUESTs if the privilege can be obtained, otherwise it will try to establish a TCP connection on port 7 (Echo) of the destination host..".
Option #1 (ICMP) usually requires administrative (root)
rights.
I think this code will help you:
public class PingExample {
public static void main(String[] args){
try{
InetAddress address = InetAddress.getByName("192.168.1.103");
boolean reachable = address.isReachable(10000);
System.out.println("Is host reachable? " + reachable);
} catch (Exception e){
e.printStackTrace();
}
}
}
Check your connectivity. On my Computer this prints REACHABLE for both IP's:
Sending Ping Request to 127.0.0.1
Host is reachable
Sending Ping Request to 173.194.32.38
Host is reachable
EDIT:
You could try modifying the code to use getByAddress() to obtain the address:
public static void main(String[] args) throws UnknownHostException, IOException {
InetAddress inet;
inet = InetAddress.getByAddress(new byte[] { 127, 0, 0, 1 });
System.out.println("Sending Ping Request to " + inet);
System.out.println(inet.isReachable(5000) ? "Host is reachable" : "Host is NOT reachable");
inet = InetAddress.getByAddress(new byte[] { (byte) 173, (byte) 194, 32, 38 });
System.out.println("Sending Ping Request to " + inet);
System.out.println(inet.isReachable(5000) ? "Host is reachable" : "Host is NOT reachable");
}
The getByName() methods may attempt some kind of reverse DNS lookup which may not be possible on your machine, getByAddress() might bypass that.