/// <summary>
/// Removes the specified association from the <see cref="ConcurrentDictionaryKey{TKey,TValue}"/>, comparing both key and value.
/// </summary>
/// <param name="item">A <see cref="KeyValuePair{TKey,TValue}"/> representing the association to remove.</param>
/// <returns>true if the association was successfully removed from the <see cref="ConcurrentDictionaryKey{TKey,TValue}"/>;
/// otherwise, false. This method also returns false if the association is not found in
/// the original <see cref="ConcurrentDictionaryKey{TKey,TValue}"/>.
///</returns>
bool ICollection <KeyValuePair <TKey, TValue> > .Remove(KeyValuePair <TKey, TValue> item)
{
KeyValuePair <TKey, TValue>? oldItem;
ConcurrentDictionaryKey <TKey, TValue> searchKey = new ConcurrentDictionaryKey <TKey, TValue>(item.Key, item.Value);
return(base.RemoveItem(ref searchKey, out oldItem));
}
public TValue AddOrUpdate(TKey key, Func <TKey, TValue> addValueFactory, Func <TKey, TValue, TValue> updateValueFactory)
{
if (null == addValueFactory)
{
throw new ArgumentNullException("addValueFactory");
}
if (null == updateValueFactory)
{
throw new ArgumentNullException("updateValueFactory");
}
var searchKey = new ConcurrentDictionaryKey <TKey, TValue>(key);
KeyValuePair <TKey, TValue>?latestItem;
while (true)
{
if (this.FindItem(ref searchKey, out latestItem))
{
TValue storedValue = latestItem.Value.Value;
TValue newValue = updateValueFactory(key, storedValue);
if (TryUpdate(key, newValue, storedValue))
{
return(newValue);
}
}
else
{
return(AddOrUpdate(key, addValueFactory(key), updateValueFactory));
}
}
}
/// <summary>
/// Removes the element with the specified key from the dictionary.
/// </summary>
/// <param name="key">The key of the element to remove.</param>
/// <returns>true if the element is successfully removed; otherwise, false. This method
/// also returns false if key was not found in the original dictionary.</returns>
bool IDictionary <TKey, TValue> .Remove(TKey key)
{
KeyValuePair <TKey, TValue>? oldItem;
ConcurrentDictionaryKey <TKey, TValue> searchKey = new ConcurrentDictionaryKey <TKey, TValue>(key);
return(base.RemoveItem(ref searchKey, out oldItem));
}
/// <summary>
/// Determines whether the dictionary
/// contains an element with the specified key.
/// </summary>
/// <param name="key">The key to locate in the dictionary.</param>
/// <returns>true if the dictionary contains
/// an element with the key; otherwise, false.</returns>
public bool ContainsKey(TKey key)
{
KeyValuePair <TKey, TValue>? presentItem;
ConcurrentDictionaryKey <TKey, TValue> searchKey = new ConcurrentDictionaryKey <TKey, TValue>(key);
return(FindItem(ref searchKey, out presentItem));
}
/// <summary>
/// Determines whether the specified association exists in the dictionary.
/// </summary>
/// <param name="item">The key-value association to search fo in the dicionary.</param>
/// <returns>True if item is found in the dictionary; otherwise, false.</returns>
/// <remarks>
/// This method compares both key and value. It uses the default equality comparer to compare values.
/// </remarks>
bool ICollection <KeyValuePair <TKey, TValue> > .Contains(KeyValuePair <TKey, TValue> item)
{
KeyValuePair <TKey, TValue>? presentItem;
ConcurrentDictionaryKey <TKey, TValue> searchKey = new ConcurrentDictionaryKey <TKey, TValue>(item.Key, item.Value);
return
(FindItem(ref searchKey, out presentItem));
}
public bool TryRemove(TKey key, out TValue value)
{
var searchKey = new ConcurrentDictionaryKey <TKey, TValue>(key);
KeyValuePair <TKey, TValue>?oldItem;
var res = base.RemoveItem(ref searchKey, out oldItem);
value = res ? oldItem.Value.Value : default(TValue);
return(res);
}
public bool TryUpdate(
TKey key,
TValue newValue,
TValue comparisonValue
)
{
var searchKey = new ConcurrentDictionaryKey <TKey, TValue>(key);
KeyValuePair <TKey, TValue>?newItem = new KeyValuePair <TKey, TValue>(key, newValue);
KeyValuePair <TKey, TValue>?dummy;
return(base.ReplaceItem(ref searchKey, ref newItem, out dummy, item => EqualityComparer <TValue> .Default.Equals(item.Value.Value, comparisonValue)));
}
/// <summary>
/// Gets the value associated with the specified key.
/// </summary>
/// <param name="key">The key whose value to get.</param>
/// <param name="value">
/// When this method returns, the value associated with the specified key, if
/// the key is found; otherwise, the default value for the type of the value
/// parameter. This parameter is passed uninitialized.
///</param>
/// <returns>
/// true if the dictionary contains an element with the specified key; otherwise, false.
/// </returns>
public bool TryGetValue(TKey key, out TValue value)
{
KeyValuePair <TKey, TValue>? presentItem;
ConcurrentDictionaryKey <TKey, TValue> searchKey = new ConcurrentDictionaryKey <TKey, TValue>(key);
var res = FindItem(ref searchKey, out presentItem);
if (res)
{
value = presentItem.Value.Value;
return(true);
}
else
{
value = default(TValue);
return(false);
}
}
/// <summary>
/// Gets or sets the value associated with the specified key.
/// </summary>
/// <param name="key">The key of the value to get or set.</param>
/// <returns>The value associated with the specified key. If the specified key is not found, a get operation throws a KeyNotFoundException, and a set operation creates a new element with the specified key.</returns>
/// <remarks>
/// When working with multiple threads, that can each potentialy remove the searched for item, a <see cref="KeyNotFoundException"/> can always be expected.
/// </remarks>
public TValue this[TKey key]
{
get
{
KeyValuePair <TKey, TValue>? presentItem;
ConcurrentDictionaryKey <TKey, TValue> searchKey = new ConcurrentDictionaryKey <TKey, TValue>(key);
if (!FindItem(ref searchKey, out presentItem))
{
throw new KeyNotFoundException("The property is retrieved and key is not found.");
}
return(presentItem.Value.Value);
}
set
{
KeyValuePair <TKey, TValue>?newItem = new KeyValuePair <TKey, TValue>(key, value);
KeyValuePair <TKey, TValue>?presentItem;
InsertItem(ref newItem, out presentItem);
}
}
public TValue GetOrAdd(
TKey key,
Func <TKey, TValue> valueFactory
)
{
if (null == valueFactory)
{
throw new ArgumentNullException("valueFactory");
}
var searchKey = new ConcurrentDictionaryKey <TKey, TValue>(key);
KeyValuePair <TKey, TValue>?oldItem;
if (base.FindItem(ref searchKey, out oldItem))
{
return(oldItem.Value.Value);
}
KeyValuePair <TKey, TValue>?newItem = new KeyValuePair <TKey, TValue>(key, valueFactory(key));
base.GetOldestItem(ref newItem, out oldItem);
return(oldItem.Value.Value);
}
/// <summary>
/// Compares a storeable item to a search key. Should return true if they match.
/// </summary>
/// <param name="item">Reference to the storeable item to compare.</param>
/// <param name="key">Reference to the search key to compare.</param>
/// <returns>True if the storeable item and search key match; false otherwise.</returns>
internal protected override bool ItemEqualsKey(ref KeyValuePair <TKey, TValue>?item, ref ConcurrentDictionaryKey <TKey, TValue> key)
{
return(item.HasValue && _Comparer.Equals(item.Value.Key, key._Key) && (key._IgnoreValue || EqualityComparer <TValue> .Default.Equals(item.Value.Value, key._Value)));
}
/// <summary>
/// Get a hashcode for given search key.
/// </summary>
/// <param name="key">Reference to the key to get a hash value for.</param>
/// <returns>The hash value as an <see cref="UInt32"/>.</returns>
/// <remarks>
/// The hash returned should be properly randomized hash. The standard GetItemHashCode methods are usually not good enough.
/// A storeable item and a matching search key should return the same hash code.
/// So the statement <code>ItemEqualsItem(storeableItem, searchKey) ? GetItemHashCode(storeableItem) == GetItemHashCode(searchKey) : true </code> should always be true;
/// </remarks>
internal protected override UInt32 GetKeyHashCode(ref ConcurrentDictionaryKey <TKey, TValue> key)
{
return(Hasher.Rehash(_Comparer.GetHashCode(key._Key)));
}
