public NodeDescriptor getSingleSubscribedBroker(Filter filter) {
NodeDescriptor foundBroker = null;
// iterates over the subscribed neighbors
Set keys = data.keySet();
synchronized (data) {
Iterator it = keys.iterator();
while (it.hasNext()) {
NodeDescriptor currentNeighbor = (NodeDescriptor) it.next();
if (((Collection) data.get(currentNeighbor)).contains(filter)) {
if (foundBroker != null || !currentNeighbor.isBroker()) { // more
// than
// one
// broker
// found
// or
// a
// client
// found
return null;
}
foundBroker = currentNeighbor;
}
}
}
return foundBroker;
}
public void addSubscription(NodeDescriptor n, Filter f) {
List filters = (List) data.get(n);
if (filters == null) {
filters = new ArrayList();
filters.add(f);
data.put(n, filters);
} else {
if (!filters.contains(f)) filters.add(f);
}
}
public Collection getSubscribedNeighbors(Filter f) {
List matchingNeighbors = new ArrayList();
// iterates over the subscribed neighbors
Set keys = data.keySet();
synchronized (data) {
Iterator it = keys.iterator();
NodeDescriptor currentNeighbor;
while (it.hasNext()) {
currentNeighbor = (NodeDescriptor) it.next();
// Check if currentNeighbor is subscribed to the message
if (((Collection) data.get(currentNeighbor)).contains(f)) {
matchingNeighbors.add(currentNeighbor);
}
}
}
return matchingNeighbors;
}
// *** For debug purposes
public String toString() {
StringBuffer result = new StringBuffer(super.toString() + "\n");
// iterates over the subscribed neighbors
Set keys = data.keySet();
synchronized (data) {
Iterator it = keys.iterator();
NodeDescriptor currentNeighbor;
while (it.hasNext()) {
currentNeighbor = (NodeDescriptor) it.next();
result.append(" " + currentNeighbor + " is subscribed to:\n");
// iterates over the set of filters for currentNeighbor
Iterator it1 = ((Collection) data.get(currentNeighbor)).iterator();
Filter f;
while (it1.hasNext()) {
f = (Filter) it1.next();
result.append(" " + f + "\n");
}
}
}
return result.toString();
}
public boolean isFilterInTable(Filter filter) {
Collection val = data.values();
synchronized (data) {
Iterator it = val.iterator();
Collection c;
while (it.hasNext()) {
c = (Collection) it.next();
if (c.contains(filter)) return true;
}
}
return false;
}
public Collection getAllFiltersExcept(boolean duplicate, NodeDescriptor n) {
Collection result = new ArrayList();
Set keys = data.keySet();
synchronized (data) {
Iterator it = keys.iterator();
NodeDescriptor currentNeighbor;
while (it.hasNext()) {
currentNeighbor = (NodeDescriptor) it.next();
if (currentNeighbor.equals(n)) continue; // skip neighbor n
Collection filters = (Collection) data.get(currentNeighbor);
if (duplicate) result.addAll(filters);
else {
Iterator it1 = filters.iterator();
while (it1.hasNext()) {
Filter f = (Filter) it1.next();
if (!result.contains(f)) result.add(f);
}
}
}
}
return result;
}
public Collection matches(Message message, NodeDescriptor senderID) {
List matchingNeighbors = new ArrayList();
// iterates over the subscribed neighbors
Set keys = data.keySet();
synchronized (data) {
Iterator it = keys.iterator();
NodeDescriptor currentNeighbor;
while (it.hasNext()) {
currentNeighbor = (NodeDescriptor) it.next();
// Check if currentNeighbor is subscribed to the message
// iterates over the set of filters for currentNeighbor
if (senderID.equals(currentNeighbor)) continue;
Iterator it1 = ((Collection) data.get(currentNeighbor)).iterator();
while (it1.hasNext()) {
Filter f = (Filter) it1.next();
if (f.matches(message)) {
matchingNeighbors.add(currentNeighbor);
break;
}
}
}
}
return matchingNeighbors;
}
public Collection getAllFilters(NodeDescriptor n) {
return (List) data.get(n);
}
public boolean isSubscribed(NodeDescriptor n) {
List filters = (List) data.get(n);
return filters != null && !filters.isEmpty();
}
public void clear() {
data.clear();
}
public void removeAllSubscriptions(NodeDescriptor n) {
data.remove(n);
}
public void removeSubscription(NodeDescriptor n, Filter f) {
List filters = (List) data.get(n);
if (filters != null) {
filters.remove(f);
}
}