/*
* Connect a UDP socket, disconnect it, then send and recv on it.
* It will fail on Linux if we don't silently bind(2) again at the
* end of DatagramSocket.disconnect().
*/
private static void testConnectedUDP(InetAddress addr) throws Exception {
try {
DatagramSocket s = new DatagramSocket(0, addr);
DatagramSocket ss = new DatagramSocket(0, addr);
System.out.print("\tconnect...");
s.connect(ss.getLocalAddress(), ss.getLocalPort());
System.out.print("disconnect...");
s.disconnect();
byte[] data = {0, 1, 2};
DatagramPacket p =
new DatagramPacket(data, data.length, s.getLocalAddress(), s.getLocalPort());
s.setSoTimeout(10000);
System.out.print("send...");
s.send(p);
System.out.print("recv...");
s.receive(p);
System.out.println("OK");
ss.close();
s.close();
} catch (Exception e) {
e.printStackTrace();
throw e;
}
}
/**
* Returns an InetAddress instance that represents the localhost, and that a socket can bind upon
* or distribute to peers as a contact address.
*
* @param intendedDestination the destination that we'd like to use the localhost address with.
* @return an InetAddress instance representing the local host, and that a socket can bind upon or
* distribute to peers as a contact address.
*/
public synchronized InetAddress getLocalHost(InetAddress intendedDestination) {
// no point in making sure that the localHostFinderSocket is initialized.
// better let it through a NullPointerException.
InetAddress localHost = null;
localHostFinderSocket.connect(intendedDestination, this.RANDOM_ADDR_DISC_PORT);
localHost = localHostFinderSocket.getLocalAddress();
localHostFinderSocket.disconnect();
// windows socket implementations return the any address so we need to
// find something else here ... InetAddress.getLocalHost seems to work
// better on windows so lets hope it'll do the trick.
if (localHost.isAnyLocalAddress()) {
try {
// all that's inside the if is an ugly IPv6 hack
// (good ol' IPv6 - always causing more problems than it solves.)
if (intendedDestination instanceof Inet6Address) {
// return the first globally routable ipv6 address we find
// on the machine (and hope it's a good one)
Enumeration interfaces = NetworkInterface.getNetworkInterfaces();
while (interfaces.hasMoreElements()) {
NetworkInterface iface = (NetworkInterface) interfaces.nextElement();
Enumeration addresses = iface.getInetAddresses();
while (addresses.hasMoreElements()) {
InetAddress address = (InetAddress) addresses.nextElement();
if (address instanceof Inet6Address) {
if (!address.isAnyLocalAddress()
&& !address.isLinkLocalAddress()
&& !address.isSiteLocalAddress()
&& !address.isLoopbackAddress()) {
return address;
}
}
}
}
} else localHost = InetAddress.getLocalHost();
/** @todo test on windows for ipv6 cases */
} catch (Exception ex) {
// sigh ... ok return 0.0.0.0
logger.warn("Failed to get localhost ", ex);
}
}
return localHost;
}