/**
* Handles a message. Knows type "collectiveUpdate-"+name only. It is the responsibility of the
* owner to propagate messages of this type using this method.
*/
public boolean handleMessage(Message m, Object o) {
if (!shouldLive || !m.getType().equals("collectiveUpdate-" + name)) return false;
final String logSender = observer + "#collectiveUpdate";
Logger.debug(logSender, "Update from " + m.getSender());
/**/
if (!m.getRecipient().name.equals(contributor.getName()))
Logger.warning(
logSender,
"Recipient and my contributor are not the same:\n"
+ "Recipient: "
+ m.getRecipient().name
+ "\n"
+ "Contributor: "
+ contributor.getName(),
null);
/**/
Collective c = (Collective) o;
// --- reset array representations
cacheCollection = null;
commandCollection = null;
// --- remove possible garbage
cache.remove(m.getRecipient().name);
c.cache.remove(m.getRecipient().name);
cache.remove(m.getSender().name);
c.cache.remove(m.getSender().name);
// --- sending our contributions
if (contributor == null)
Logger.warning(logSender, "Non-contributor observer is known by " + m.getSender(), null);
updateLocalInfo();
m.setReply(this);
// --- update containers
repairSenderAddress(c, m.getSender());
merge(c);
observer.collectiveUpdated((ContributionBox) cache.get(m.getSender().name));
return true;
}
/**
* Construct a Collective object.
*
* @param c The contributions, the commands and the name will be initialized from this object.
* @param o The observer that reads information from the collective. It must be non-null.
* @param cb The contributor that contributes to the collective effort.
* @param c The controller that issues collective-wide commands.
*/
public Collective(Collective c, Observer o, Contributor cb, Controller cr) {
this(c.name, o, cb, cr);
if (c == null) throw new IllegalArgumentException("null collective");
if (c.cache != null) cache.putAll(c.cache);
if (c.commands != null) commands.putAll(c.commands);
if (contributor != null) cache.remove(contributor.getName());
}
/**
* Updates local contribution and commands. Called before information exchange attempts. Uses
* local address of contributor (if it is not null), this is replaced on the other side of the
* communication channel by the correct global address.
*/
private synchronized void updateLocalInfo() {
if (contributor != null) {
myContribution =
new ContributionBox(new Address(contributor.getName()), contributor.getContribution());
}
final Long now = new Long(System.currentTimeMillis());
if (controller != null) {
Set newcomms = controller.getCommands();
if (newcomms == null) return;
Iterator i = newcomms.iterator();
while (i.hasNext()) commands.put(i.next(), now);
}
}
/**
* Initiates an information exchange with a known and living other base if such a base exists.
*
* @return true if refresh was succesful, false otherwise.
*/
private boolean refresh() {
final String logSender = observer + "#refresh";
final String contrName = ((contributor != null) ? contributor.getName() : null);
// --- refreshing local contribution and commands
updateLocalInfo();
// --- creating a random permutation of peers
Vector peers = null;
synchronized (cache) {
peers = new Vector(cache.values());
// just to be sure, shouldn't be there anyway
if (contrName != null) peers.remove(cache.get(contrName));
}
Collections.shuffle(peers);
if (peers.isEmpty()) {
Logger.debug(logSender, "no peers in cache");
return false;
}
// --- reset array representations
cacheCollection = null;
commandCollection = null;
// --- trying to talk to random peer
IRequest answer = null;
Address peer = null;
for (int i = 0; i < peers.size(); ++i) {
if (!shouldLive) return false;
peer = ((ContributionBox) peers.get(i)).contributor;
Logger.debug(logSender, "asking " + peer);
answer = observer.fireMessage(peer, "collectiveUpdate-" + name, this);
while (answer.getStatus() == IRequest.WAITING) {
try {
Thread.sleep(100);
} catch (Exception e) {
}
}
if (answer.getStatus() == IRequest.DONE) break;
Logger.debug(logSender, "not accessable: " + peer);
}
if (answer.getStatus() != IRequest.DONE) {
Logger.debug(logSender, "no accessable peers");
observer.collectiveUpdated(null);
return false;
} else {
Collective c = (Collective) answer.getInfo("reply");
// --- remove possible garbage
if (contributor != null) {
cache.remove(contributor.getName());
c.cache.remove(contributor.getName());
}
cache.remove(peer.name);
c.cache.remove(peer.name);
repairSenderAddress(c, peer);
merge(c);
observer.collectiveUpdated((ContributionBox) cache.get(c.myContribution.contributor.name));
return true;
}
}