// ------------------------------------------------------------------------
// TmfProvider
// ------------------------------------------------------------------------
@Override
public ITmfContext armRequest(ITmfDataRequest<T> request) {
// Tracer.trace("Ctx: Arming request - start");
TmfTimestamp timestamp =
(request instanceof ITmfEventRequest<?>)
? ((ITmfEventRequest<T>) request).getRange().getStartTime()
: null;
if (TmfTimestamp.BigBang.equals(timestamp) || request.getIndex() > 0) {
timestamp = null; // use request index
}
TmfExperimentContext context = null;
if (timestamp != null) {
// seek by timestamp
context = seekEvent(timestamp);
((ITmfEventRequest<T>) request).setStartIndex((int) context.getRank());
} else {
// Seek by rank
if ((fExperimentContext != null) && fExperimentContext.getRank() == request.getIndex()) {
// We are already at the right context -> no need to seek
context = fExperimentContext;
} else {
context = seekEvent(request.getIndex());
}
}
// Tracer.trace("Ctx: Arming request - done");
return context;
}
/*
* (non-Javadoc)
*
* @see org.eclipse.linuxtools.tmf.trace.ITmfTrace#seekEvent(long)
*/
@Override
public synchronized TmfExperimentContext seekEvent(long rank) {
// Tracer.trace("Ctx: seekEvent(rank) - start");
// Position the stream at the previous checkpoint
int index = (int) rank / fIndexPageSize;
ITmfLocation<?> location;
synchronized (fCheckpoints) {
if (fCheckpoints.size() == 0) {
location = null;
} else {
if (index >= fCheckpoints.size()) {
index = fCheckpoints.size() - 1;
}
location = fCheckpoints.elementAt(index).getLocation();
}
}
TmfExperimentContext context = seekLocation(location);
context.setRank((long) index * fIndexPageSize);
// And locate the event
TmfEvent event = parseEvent(context);
long pos = context.getRank();
while (event != null && pos++ < rank) {
getNextEvent(context);
event = parseEvent(context);
}
if (event == null) {
context.setLocation(null);
context.setRank(ITmfContext.UNKNOWN_RANK);
}
return context;
}
/**
* Returns the rank of the first event with the requested timestamp. If none, returns the index of
* the next event (if any).
*
* @param timestamp
* @return
*/
@Override
public long getRank(TmfTimestamp timestamp) {
TmfExperimentContext context = seekEvent(timestamp);
return context.getRank();
}
