/**
* Gathers UPnP candidates for all host <tt>Candidate</tt>s that are already present in the
* specified <tt>component</tt>. This method relies on the specified <tt>component</tt> to already
* contain all its host candidates so that it would resolve them.
*
* @param component the {@link Component} that we'd like to gather candidate UPnP
* <tt>Candidate</tt>s for
* @return the <tt>LocalCandidate</tt>s gathered by this <tt>CandidateHarvester</tt>
*/
public synchronized Collection<LocalCandidate> harvest(Component component) {
Collection<LocalCandidate> candidates = new HashSet<>();
int retries = 0;
logger.fine("Begin UPnP harvesting");
try {
if (device == null) {
// do it only once
if (finishThreads == 0) {
try {
UPNPThread wanIPThread = new UPNPThread(stIP);
UPNPThread wanPPPThread = new UPNPThread(stPPP);
wanIPThread.start();
wanPPPThread.start();
synchronized (rootSync) {
while (finishThreads != 2) {
rootSync.wait();
}
}
if (wanIPThread.getDevice() != null) {
device = wanIPThread.getDevice();
} else if (wanPPPThread.getDevice() != null) {
device = wanPPPThread.getDevice();
}
} catch (Throwable e) {
logger.info("UPnP discovery failed: " + e);
}
}
if (device == null) return candidates;
}
InetAddress localAddress = device.getLocalAddress();
String externalIPAddress = device.getExternalIPAddress();
PortMappingEntry portMapping = new PortMappingEntry();
IceSocketWrapper socket =
new IceUdpSocketWrapper(new MultiplexingDatagramSocket(0, localAddress));
int port = socket.getLocalPort();
int externalPort = socket.getLocalPort();
while (retries < MAX_RETRIES) {
if (!device.getSpecificPortMappingEntry(port, "UDP", portMapping)) {
if (device.addPortMapping(
externalPort, port, localAddress.getHostAddress(), "UDP", "ice4j.org: " + port)) {
List<LocalCandidate> cands =
createUPNPCandidate(socket, externalIPAddress, externalPort, component, device);
logger.info("Add UPnP port mapping: " + externalIPAddress + " " + externalPort);
// we have to add the UPNPCandidate and also the base.
// if we don't add the base, we won't be able to add
// peer reflexive candidate if someone contact us on the
// UPNPCandidate
for (LocalCandidate cand : cands) {
// try to add the candidate to the component and then
// only add it to the harvest not redundant
if (component.addLocalCandidate(cand)) {
candidates.add(cand);
}
}
break;
} else {
port++;
}
} else {
port++;
}
retries++;
}
} catch (Throwable e) {
logger.info("Exception while gathering UPnP candidates: " + e);
}
return candidates;
}
