/** @since 3.0 */
@Override
public synchronized ITmfContext seekEvent(final ITmfLocation location) {
// Validate the location
if (location != null && !(location instanceof TmfExperimentLocation)) {
return null; // Throw an exception?
}
// Make sure we have something to read from
if (fTraces == null) {
return null;
}
// Initialize the location array if necessary
TmfLocationArray locationArray =
((location == null)
? new TmfLocationArray(fTraces.length)
: ((TmfExperimentLocation) location).getLocationInfo());
ITmfLocation[] locations = locationArray.getLocations();
long[] ranks = locationArray.getRanks();
// Create and populate the context's traces contexts
final TmfExperimentContext context = new TmfExperimentContext(fTraces.length);
// Position the traces
long rank = 0;
for (int i = 0; i < fTraces.length; i++) {
// Get the relevant trace attributes
final ITmfContext traceContext = fTraces[i].seekEvent(locations[i]);
context.setContext(i, traceContext);
traceContext.setRank(ranks[i]);
locations[i] = traceContext.getLocation(); // update location after seek
context.setEvent(i, fTraces[i].getNext(traceContext));
rank += ranks[i];
}
// Finalize context
context.setLocation(new TmfExperimentLocation(new TmfLocationArray(locations, ranks)));
context.setLastTrace(TmfExperimentContext.NO_TRACE);
context.setRank(rank);
return context;
}
@Override
public synchronized ITmfEvent getNext(ITmfContext context) {
// Validate the context
if (!(context instanceof TmfExperimentContext)) {
return null; // Throw an exception?
}
// Make sure that we have something to read from
if (fTraces == null) {
return null;
}
TmfExperimentContext expContext = (TmfExperimentContext) context;
// If an event was consumed previously, first get the next one from that
// trace
final int lastTrace = expContext.getLastTrace();
if (lastTrace != TmfExperimentContext.NO_TRACE) {
final ITmfContext traceContext = expContext.getContext(lastTrace);
expContext.setEvent(lastTrace, fTraces[lastTrace].getNext(traceContext));
expContext.setLastTrace(TmfExperimentContext.NO_TRACE);
}
// Scan the candidate events and identify the "next" trace to read from
int trace = TmfExperimentContext.NO_TRACE;
ITmfTimestamp timestamp = TmfTimestamp.BIG_CRUNCH;
for (int i = 0; i < fTraces.length; i++) {
final ITmfEvent event = expContext.getEvent(i);
if (event != null && event.getTimestamp() != null) {
final ITmfTimestamp otherTS = event.getTimestamp();
if (otherTS.compareTo(timestamp, true) < 0) {
trace = i;
timestamp = otherTS;
}
}
}
ITmfEvent event = null;
if (trace != TmfExperimentContext.NO_TRACE) {
event = expContext.getEvent(trace);
if (event != null) {
updateAttributes(expContext, event.getTimestamp());
expContext.increaseRank();
expContext.setLastTrace(trace);
final ITmfContext traceContext = expContext.getContext(trace);
if (traceContext == null) {
throw new IllegalStateException();
}
// Update the experiment location
TmfLocationArray locationArray =
new TmfLocationArray(
((TmfExperimentLocation) expContext.getLocation()).getLocationInfo(),
trace,
traceContext.getLocation(),
traceContext.getRank());
expContext.setLocation(new TmfExperimentLocation(locationArray));
processEvent(event);
}
}
return event;
}
