/// <summary>
/// Gets a list containing all the keys in the collection.
/// </summary>
/// <returns>Returns all keys stored in <see cref="_table"/></returns>
public List <TKey> GetKeys()
{
var keys = new List <TKey>();
foreach (var node in _table)
{
MapperNode <TKey, TValue> current = node;
while (current != null)
{
keys.Add(current._key);
current = current._next;
}
}
return(keys);
}
/// <summary>
/// Double number of indices for each key properties.
/// Increase <see cref="_table"/> capacity 2^KeySize times
/// </summary>
private void ExpandTable()
{
var newSize = 0;
var newNonEmptyNodes = 0;
var newRangePerKey = _rangePerKey * 2;
var newTable = new MapperNode <TKey, TValue> [newRangePerKey.Pow(KeySize)];
lock (_table)
{
for (int i = 0; i < _table.Length; i++)
{
MapperNode <TKey, TValue> current = _table[i];
while (current != null)
{
var index = HashesToTableIndex(current._hashes, newRangePerKey);
if (newTable[index] == null)
{
newTable[index] =
new MapperNode <TKey, TValue>(current._key, current._value, current._hashes, null);
newNonEmptyNodes++;
newSize++;
}
else
{
newTable[index].Add(current._key, current._value, current._hashes, out var added);
newSize += added;
}
current = current._next;
}
}
_rangePerKey = newRangePerKey;
_table = newTable;
NonEmptyNodes = newNonEmptyNodes;
Size = newSize;
}
}
/// <summary>
/// Indexer, which allows to get and also set values of a collection by a key.
/// </summary>
/// <param name="key">Received key value</param>
/// <exception cref="ArgumentNullException"></exception>
public TValue this[TKey key]
{
set
{
if (key == null)
{
throw new ArgumentNullException(nameof(key));
}
if (value == null)
{
throw new ArgumentNullException(nameof(value));
}
lock (_keys) _keys.Add(key); // should contain unique values but cause performance
if (NonEmptyNodes == Capacity)
{
ExpandTable();
}
var hashes = HashesOfKey(key);
var index = HashesToTableIndex(hashes, _rangePerKey);
if (_table[index] == null)
{
_table[index] = new MapperNode <TKey, TValue>(key, value, hashes, null);
NonEmptyNodes++;
Size++;
}
else
{
lock (_table[index])
{
_table[index].Add(key, value, hashes, out var added);
Size += added;
}
}
}
get
{
if (key == null)
{
throw new ArgumentNullException(nameof(key));
}
var index = KeyToTableIndex(key, _rangePerKey);
var node = _table[index];
while (node != null)
{
MapperNode <TKey, TValue> next;
lock (node)
{
if (IsKeysEqual(node._key, key))
{
return(node._value);
}
next = node._next;
}
node = next;
}
return(default(TValue));
}
}