/// <summary>
/// Attempts to add the specified key and associated value.
/// </summary>
/// <param name="key">The key.</param>
/// <param name="value">The value.</param>
/// <param name="offset">The offset from the default index.</param>
/// <param name="isCollision">if set to <c>true</c> the attempt resulted in a collision.</param>
/// <returns>The index where the key and associated value were added.</returns>
public int Add(TKey key, TValue value, int offset, out bool isCollision)
{
int index = Index(key, offset);
var entry = new KeyValuePair <TKey, TValue>(key, value);
KeyValuePair <TKey, TValue> previous;
if (_entries.Insert(index, entry, out previous))
{
isCollision = false;
return(index);
}
else
{
isCollision = !_keyComparer.Equals(previous.Key, key);
return(-1);
}
}
/// <summary>
/// Attempts to add the specified item.
/// </summary>
/// <param name="item">The item.</param>
/// <param name="offset">The offset from the default index.</param>
/// <param name="isCollision">if set to <c>true</c> the attempt resulted in a collision.</param>
/// <returns>The index where the item were added.</returns>
public int Add(T item, int offset, out bool isCollision)
{
int index = Index(item, offset);
T previous;
if (_entries.Insert(index, item, out previous))
{
isCollision = false;
return(index);
}
else
{
isCollision = !_comparer.Equals(previous, item);
return(-1);
}
}
/// <summary>
/// Attempts to Adds the specified item at the front.
/// </summary>
/// <param name="item">The item.</param>
/// <returns>
/// <c>true</c> if the item was added; otherwise, <c>false</c>.
/// </returns>
public bool Enqueue(T item)
{
if (_bucket.Count < _capacity)
{
var preCount = Interlocked.Increment(ref _preCount);
if (preCount <= _capacity)
{
var index = (Interlocked.Increment(ref _indexEnqueue) - 1) & (_capacity - 1);
if (_bucket.Insert(index, item))
{
return(true);
}
}
Interlocked.Decrement(ref _preCount);
}
return(false);
}
/// <summary>
/// Inserts the item at the specified index.
/// </summary>
/// <param name="index">The index.</param>
/// <param name="item">The item.</param>
/// <returns>
/// <c>true</c> if the item was inserted; otherwise, <c>false</c>.
/// </returns>
/// <exception cref="System.ArgumentOutOfRangeException">index;index must be greater or equal to 0 and less than capacity.</exception>
/// <remarks>
/// The insertion can fail if the index is already used or is being written by another thread.
/// If the index is being written it can be understood that the insert operation happened before but the item was overwritten or removed.
/// </remarks>
public bool Insert(int index, T item)
{
return(_wrapped.Insert(index, item));
}