AtomicInteger counter = logFileIDReferenceCounts.get(fileID);
if(counter == null) {
counter = new AtomicInteger(0);
logFileIDReferenceCounts.put(fileID, counter);
}
counter.incrementAndGet();
}
@Override
protected void decrementFileID(int fileID) {
AtomicInteger counter = logFileIDReferenceCounts.get(fileID);
Preconditions.checkState(counter != null, "null counter ");