boolean processKeys(@NotNull Processor<? super Key> processor) throws IOException {
    return myKeyDescriptor instanceof InlineKeyDescriptor
           // process keys and check that they're already present in map because we don't have separated key storage we must check keys
           ? myPersistentMap.processExistingKeys(processor)
           // optimization: process all keys, some of them might be already deleted but we don't care. We just read key storage file here
           : myPersistentMap.processKeys(processor);
  }
boolean processKeys(@NotNull Processor<? super Key> processor)