public NodeHandle pickNextHop(RouteMessage msg, Iterator<NodeHandle> i) {
NodeHandle first = i.next();
if (first.getLiveness() < NodeHandle.LIVENESS_SUSPECTED) {
return first;
}
while (i.hasNext()) {
NodeHandle nh = i.next();
if (nh.getLiveness() < NodeHandle.LIVENESS_SUSPECTED) {
return nh;
}
// do this in case first is dead, and we find a suspected node to pass it to
if (first.getLiveness() > nh.getLiveness()) first = nh;
}
if (first.getLiveness() >= NodeHandle.LIVENESS_DEAD) {
// drop the message, this would happen if we gave a lease to this node
// but found him faulty.
return null;
}
msg.getOptions().setRerouteIfSuspected(false);
return first; // always want to return someone...
}
/**
* checks to see if the previous node along the path was missing a RT entry if so, we send the
* previous node the corresponding RT row to patch the hole
*
* @param msg the RouteMessage being routed
* @param handle the next hop handle
*/
private void checkForRouteTableHole(RouteMessage msg, NodeHandle handle) {
if (logger.level <= Logger.FINEST)
logger.log("checkForRouteTableHole(" + msg + "," + handle + ")");
NodeHandle prevNode = msg.getPrevNode();
if (prevNode == null) {
if (logger.level <= Logger.FINER) logger.log("No prevNode defined in " + msg);
return;
}
if (prevNode.equals(getNodeHandle())) {
if (logger.level <= Logger.FINER) logger.log("prevNode is me in " + msg);
return;
}
// we don't want to send the repair if they just routed in the leafset
LeafSet ls = thePastryNode.getLeafSet();
if (ls.overlaps()) return; // small network, don't bother
if (ls.member(prevNode)) {
// ok, it's in my leafset, so I'm in his, but make sure that it's not on the edge
int index = ls.getIndex(prevNode);
if ((index == ls.cwSize()) || (index == -ls.ccwSize())) {
// it is the edge... continue with repair
} else {
return;
}
}
Id prevId = prevNode.getNodeId();
Id key = msg.getTarget();
int diffDigit = prevId.indexOfMSDD(key, thePastryNode.getRoutingTable().baseBitLength());
// if we both have the same prefix (in other words the previous node didn't make a prefix of
// progress)
if (diffDigit >= 0
&& diffDigit
== thePastryNode
.getNodeId()
.indexOfMSDD(key, thePastryNode.getRoutingTable().baseBitLength())) {
synchronized (lastTimeSentRouteTablePatch) {
if (lastTimeSentRouteTablePatch.containsKey(prevNode)) {
long lastTime = lastTimeSentRouteTablePatch.get(prevNode);
if (lastTime
> (thePastryNode.getEnvironment().getTimeSource().currentTimeMillis()
- ROUTE_TABLE_PATCH_THROTTLE)) {
if (logger.level <= Logger.INFO)
logger.log(
"not sending route table patch to "
+ prevNode
+ " because throttled. Last Time:"
+ lastTime);
return;
}
}
lastTimeSentRouteTablePatch.put(
prevNode, thePastryNode.getEnvironment().getTimeSource().currentTimeMillis());
}
// the previous node is missing a RT entry, send the row
// for now, we send the entire row for simplicity
RouteSet[] row = thePastryNode.getRoutingTable().getRow(diffDigit);
BroadcastRouteRow brr = new BroadcastRouteRow(thePastryNode.getLocalHandle(), row);
if (prevNode.isAlive()) {
if (logger.level <= Logger.FINE) {
logger.log(
"Found hole in " + prevNode + "'s routing table. Sending " + brr.toStringFull());
}
thePastryNode.send(prevNode, brr, null, options);
}
}
}