protected byte[] returnPossiblePrevValue(Transport transport) {
if (hasForceReturn(flags)) {
byte[] bytes = transport.readArray();
if (log.isTraceEnabled())
log.tracef("Previous value bytes is: %s", Util.printArray(bytes, false));
// 0-length response means null
return bytes.length == 0 ? null : bytes;
} else {
return null;
}
}
@Override
public SocketAddress getServer(Object key) {
int keyHashCode = getNormalizedHash(key);
if (keyHashCode == Integer.MIN_VALUE) keyHashCode += 1;
int hash = Math.abs(keyHashCode);
SortedMap<Integer, SocketAddress> candidates = positions.tailMap(hash % hashSpace);
if (log.isTraceEnabled()) {
log.tracef("Found possible candidates: %s", candidates);
}
return (candidates.size() > 0 ? candidates : positions)
.entrySet()
.iterator()
.next()
.getValue();
}
@Override
public void init(
Map<SocketAddress, Set<Integer>> servers2Hash, int numKeyOwners, int hashSpace) {
log.infof(
"Parameters received by CH are: server2Hash: %s, numKeyOwners: %s, hashSpace: %s",
servers2Hash, numKeyOwners, hashSpace);
for (Map.Entry<SocketAddress, Set<Integer>> entry : servers2Hash.entrySet()) {
SocketAddress addr = entry.getKey();
for (Integer hash : entry.getValue()) {
SocketAddress prev = positions.put(hash, addr);
if (prev != null)
log.debugf(
"Adding hash (%d) again, this time for %s. Previously it was associated with: %s",
hash, addr, prev);
}
}
log.tracef("Positions (%d entries) are: %s", positions.size(), positions);
this.hashSpace = hashSpace;
this.numKeyOwners = numKeyOwners;
}