int keyHash = Hashing.smearedHash(key);
    int keyEntry = findEntryByKey(key, keyHash);
    if (force) {
      if (keyEntry != ABSENT) {
        predecessor = prevInInsertionOrder[keyEntry];
        removeEntryKeyHashKnown(keyEntry, keyHash);
      }
    } else {
      checkArgument(keyEntry == ABSENT, "Key already present: %s", key);
    }

    // insertion point for new entry is after predecessor