if (oldEntryForValue != null) {
      if (force) {
        delete(oldEntryForValue);
      } else {
        throw new IllegalArgumentException("value already present: " + value);
      }
    }

    BiEntry<K, V> newEntry = new BiEntry<>(key, keyHash, value, valueHash);
    if (oldEntryForKey != null) {
      delete(oldEntryForKey);
      insert(newEntry, oldEntryForKey);

    }

    // insertion point for new entry is after predecessor
    // note predecessor must still be a valid entry: either we deleted an entry that was *not*
    // predecessor, or we didn't delete anything

    ensureCapacity(size + 1);
    keys[size] = key;
    values[size] = value;

    insertIntoTableKToV(size, keyHash);
    insertIntoTableVToK(size, valueHash);