private synchronized void checkPrefixChanged(ProcessingContext context) {
    int actualPrefixChanges = context.get(CompletionLookupArranger.PREFIX_CHANGES);
    if (myWeigher.isPrefixDependent() && myPrefixChanges != actualPrefixChanges) {
      myPrefixChanges = actualPrefixChanges;
      myWeights.clear();
    }
  }
private synchronized void checkPrefixChanged(ProcessingContext context)