Files
KinginfoGateway/src/Admin/ThingsGateway.NewLife.X/Collections/NonBlockingDictionary/NonBlockingDictionary.cs
2025-10-18 03:18:45 +08:00

1459 lines
64 KiB
C#

// Copyright (c) Vladimir Sadov. All rights reserved.
//
// This file is distributed under the MIT License. See LICENSE.md for details.
#nullable disable
#pragma warning disable CS8632 // The annotation for nullable reference types should only be used in code within a '#nullable' annotations context.
using System.Collections.ObjectModel;
using System.Diagnostics;
using System.Diagnostics.CodeAnalysis;
using System.Runtime.CompilerServices;
using static System.Collections.Concurrent.DictionaryImpl;
namespace System.Collections.Concurrent
{
/// <summary>
/// Represents a thread-safe and lock-free collection of keys and values.
/// </summary>
/// <typeparam name="TKey">The type of the keys in the dictionary.</typeparam>
/// <typeparam name="TValue">The type of the values in the dictionary.</typeparam>
/// <remarks>
/// All public and protected members of <see cref="NonBlockingDictionary{TKey,TValue}"/> are thread-safe and may be used
/// concurrently from multiple threads.
/// </remarks>
[DebuggerTypeProxy(typeof(IDictionaryDebugView<,>))]
[DebuggerDisplay("Count = {Count}")]
public class NonBlockingDictionary<TKey, TValue> : IDictionary<TKey, TValue>, IDictionary, IReadOnlyDictionary<TKey, TValue> where TKey : notnull
{
private readonly bool _valueIsValueType = typeof(TValue).IsValueType;
internal DictionaryImpl<TKey, TValue> _table;
internal uint _lastResizeTickMillis;
internal object _sweeperInstance;
internal int _sweepRequests;
/// <summary>The default capacity, i.e. the initial # of buckets.</summary>
/// <remarks>
/// When choosing this value, we are making a trade-off between the size of a very small dictionary,
/// and the number of resizes when constructing a large dictionary.
/// </remarks>
private const int DefaultCapacity = 0;
/// <summary>Concurrency level is ignored. However it must be > 0.</summary>
private static int DefaultConcurrencyLevel => 1;
/// <summary>
/// Initializes a new instance of the <see cref="NonBlockingDictionary{TKey,TValue}"/>
/// class that is empty, has the default concurrency level, has the default initial capacity, and
/// uses the default comparer for the key type.
/// </summary>
public NonBlockingDictionary() : this(DefaultConcurrencyLevel, DefaultCapacity, null) { }
/// <summary>
/// Initializes a new instance of the <see cref="NonBlockingDictionary{TKey,TValue}"/>
/// class that is empty, has the specified concurrency level and capacity, and uses the default
/// comparer for the key type.
/// </summary>
/// <param name="concurrencyLevel">The estimated number of threads that will update the
/// <see cref="NonBlockingDictionary{TKey,TValue}"/> concurrently.</param>
/// <param name="capacity">The initial number of elements that the <see cref="NonBlockingDictionary{TKey,TValue}"/> can contain.</param>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="concurrencyLevel"/> is less than 1.</exception>
/// <exception cref="ArgumentOutOfRangeException"> <paramref name="capacity"/> is less than 0.</exception>
public NonBlockingDictionary(int concurrencyLevel, int capacity) : this(concurrencyLevel, capacity, null) { }
/// <summary>
/// Initializes a new instance of the <see cref="NonBlockingDictionary{TKey,TValue}"/>
/// class that contains elements copied from the specified <see cref="IEnumerable{T}"/>, has the default concurrency
/// level, has the default initial capacity, and uses the default comparer for the key type.
/// </summary>
/// <param name="collection">The <see
/// cref="IEnumerable{T}"/> whose elements are copied to the new <see cref="NonBlockingDictionary{TKey,TValue}"/>.</param>
/// <exception cref="ArgumentNullException"><paramref name="collection"/> is a null reference (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentException"><paramref name="collection"/> contains one or more duplicate keys.</exception>
public NonBlockingDictionary(IEnumerable<KeyValuePair<TKey, TValue>> collection) : this(collection, null) { }
/// <summary>
/// Initializes a new instance of the <see cref="NonBlockingDictionary{TKey,TValue}"/>
/// class that is empty, has the specified concurrency level and capacity, and uses the specified
/// <see cref="IEqualityComparer{TKey}"/>.
/// </summary>
/// <param name="comparer">The <see cref="IEqualityComparer{TKey}"/> implementation to use when comparing keys.</param>
public NonBlockingDictionary(IEqualityComparer<TKey>? comparer) : this(DefaultConcurrencyLevel, DefaultCapacity, comparer) { }
/// <summary>
/// Initializes a new instance of the <see cref="NonBlockingDictionary{TKey,TValue}"/>
/// class that contains elements copied from the specified <see cref="IEnumerable"/>, has the default concurrency
/// level, has the default initial capacity, and uses the specified <see cref="IEqualityComparer{TKey}"/>.
/// </summary>
/// <param name="collection">The <see cref="IEnumerable{T}"/> whose elements are copied to the new <see cref="NonBlockingDictionary{TKey,TValue}"/>.</param>
/// <param name="comparer">The <see cref="IEqualityComparer{TKey}"/> implementation to use when comparing keys.</param>
/// <exception cref="ArgumentNullException"><paramref name="collection"/> is a null reference (Nothing in Visual Basic).</exception>
public NonBlockingDictionary(IEnumerable<KeyValuePair<TKey, TValue>> collection, IEqualityComparer<TKey>? comparer)
: this(comparer)
{
if (collection is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(collection));
}
InitializeFromCollection(collection);
}
/// <summary>
/// Initializes a new instance of the <see cref="NonBlockingDictionary{TKey,TValue}"/>
/// class that contains elements copied from the specified <see cref="IEnumerable"/>,
/// has the specified concurrency level, has the specified initial capacity, and uses the specified
/// <see cref="IEqualityComparer{TKey}"/>.
/// </summary>
/// <param name="concurrencyLevel">
/// The estimated number of threads that will update the <see cref="NonBlockingDictionary{TKey,TValue}"/> concurrently.
/// </param>
/// <param name="collection">The <see cref="IEnumerable{T}"/> whose elements are copied to the new
/// <see cref="NonBlockingDictionary{TKey,TValue}"/>.</param>
/// <param name="comparer">The <see cref="IEqualityComparer{TKey}"/> implementation to use when comparing keys.</param>
/// <exception cref="ArgumentNullException"><paramref name="collection"/> is a null reference (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="concurrencyLevel"/> is less than 1.</exception>
/// <exception cref="ArgumentException"><paramref name="collection"/> contains one or more duplicate keys.</exception>
public NonBlockingDictionary(int concurrencyLevel, IEnumerable<KeyValuePair<TKey, TValue>> collection, IEqualityComparer<TKey>? comparer)
: this(concurrencyLevel, DefaultCapacity, comparer)
{
if (collection is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(collection));
}
InitializeFromCollection(collection);
}
private void InitializeFromCollection(IEnumerable<KeyValuePair<TKey, TValue>> collection)
{
foreach (KeyValuePair<TKey, TValue> pair in collection)
{
if (pair.Key is null)
{
ThrowHelper.ThrowKeyNullException();
}
if (!this.TryAdd(pair.Key, pair.Value))
{
throw new ArgumentException("duplicate keys");
}
}
}
/// <summary>
/// Initializes a new instance of the <see cref="NonBlockingDictionary{TKey,TValue}"/>
/// class that is empty, has the specified concurrency level, has the specified initial capacity, and
/// uses the specified <see cref="IEqualityComparer{TKey}"/>.
/// </summary>
/// <param name="concurrencyLevel">The estimated number of threads that will update the <see cref="NonBlockingDictionary{TKey,TValue}"/> concurrently.</param>
/// <param name="capacity">The initial number of elements that the <see cref="NonBlockingDictionary{TKey,TValue}"/> can contain.</param>
/// <param name="comparer">The <see cref="IEqualityComparer{TKey}"/> implementation to use when comparing keys.</param>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="concurrencyLevel"/> is less than 1. -or- <paramref name="capacity"/> is less than 0.</exception>
public NonBlockingDictionary(int concurrencyLevel, int capacity, IEqualityComparer<TKey>? comparer)
{
if (concurrencyLevel < 1)
{
throw new ArgumentOutOfRangeException(nameof(concurrencyLevel));
}
if (capacity < 0)
{
throw new ArgumentOutOfRangeException(nameof(capacity));
}
// add some extra so that filled to capacity would be at 50% density
capacity = Math.Max(capacity, capacity * 2);
if (!typeof(TKey).IsValueType)
{
_table = new DictionaryImplRef<TKey, TKey, TValue>(capacity, this);
_table._keyComparer = comparer ?? EqualityComparer<TKey>.Default;
return;
}
else
{
if (typeof(TKey) == typeof(int) || (typeof(TKey) == typeof(uint) && comparer == null))
{
if (comparer == null)
{
_table = Unsafe.As<DictionaryImpl<TKey, TValue>>(new DictionaryImplIntNoComparer<TValue>(capacity, Unsafe.As<NonBlockingDictionary<int, TValue>>(this)));
}
else
{
_table = Unsafe.As<DictionaryImpl<TKey, TValue>>(new DictionaryImplInt<TValue>(capacity, Unsafe.As<NonBlockingDictionary<int, TValue>>(this)));
_table._keyComparer = comparer;
}
return;
}
if (typeof(TKey) == typeof(long) || (typeof(TKey) == typeof(ulong) && comparer == null))
{
if (comparer == null)
{
_table = Unsafe.As<DictionaryImpl<TKey, TValue>>(new DictionaryImplLongNoComparer<TValue>(capacity, Unsafe.As<NonBlockingDictionary<long, TValue>>(this)));
}
else
{
_table = Unsafe.As<DictionaryImpl<TKey, TValue>>(new DictionaryImplLong<TValue>(capacity, Unsafe.As<NonBlockingDictionary<long, TValue>>(this)));
_table._keyComparer = comparer;
}
return;
}
if (typeof(TKey) == typeof(nint) || (typeof(TKey) == typeof(nuint) && comparer == null))
{
if (comparer == null)
{
_table = Unsafe.As<DictionaryImpl<TKey, TValue>>(new DictionaryImplNintNoComparer<TValue>(capacity, Unsafe.As<NonBlockingDictionary<nint, TValue>>(this)));
}
else
{
_table = Unsafe.As<DictionaryImpl<TKey, TValue>>(new DictionaryImplNint<TValue>(capacity, Unsafe.As<NonBlockingDictionary<nint, TValue>>(this)));
_table._keyComparer = comparer;
}
return;
}
}
_table = new DictionaryImplBoxed<TKey, TValue>(capacity, this);
_table._keyComparer = comparer ?? EqualityComparer<TKey>.Default;
}
/// <summary>
/// Attempts to add the specified key and value to the <see cref="NonBlockingDictionary{TKey, TValue}"/>.
/// </summary>
/// <param name="key">The key of the element to add.</param>
/// <param name="value">The value of the element to add. The value can be a null reference (Nothing
/// in Visual Basic) for reference types.</param>
/// <returns>
/// true if the key/value pair was added to the <see cref="NonBlockingDictionary{TKey, TValue}"/> successfully; otherwise, false.
/// </returns>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is null reference (Nothing in Visual Basic).</exception>
/// <exception cref="OverflowException">The <see cref="NonBlockingDictionary{TKey, TValue}"/> contains too many elements.</exception>
public bool TryAdd(TKey key, TValue value)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
TValue oldVal = default;
return _table.PutIfMatch(key, value, ref oldVal, ValueMatch.NullOrDead);
}
/// <summary>
/// Determines whether the <see cref="NonBlockingDictionary{TKey, TValue}"/> contains the specified key.
/// </summary>
/// <param name="key">The key to locate in the <see cref="NonBlockingDictionary{TKey, TValue}"/>.</param>
/// <returns>true if the <see cref="NonBlockingDictionary{TKey, TValue}"/> contains an element with the specified key; otherwise, false.</returns>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference (Nothing in Visual Basic).</exception>
public bool ContainsKey(TKey key)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
object oldValObj = _table.TryGetValue(key);
Debug.Assert(!(oldValObj is Prime));
return oldValObj != null;
}
/// <summary>
/// Attempts to remove and return the value with the specified key from the <see cref="NonBlockingDictionary{TKey, TValue}"/>.
/// </summary>
/// <param name="key">The key of the element to remove and return.</param>
/// <param name="value">
/// When this method returns, <paramref name="value"/> contains the object removed from the
/// <see cref="NonBlockingDictionary{TKey,TValue}"/> or the default value of <typeparamref
/// name="TValue"/> if the operation failed.
/// </param>
/// <returns>true if an object was removed successfully; otherwise, false.</returns>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference (Nothing in Visual Basic).</exception>
#if NETSTANDARD2_1_OR_GREATER || NETCOREAPP || NETCOREAPP
public bool TryRemove(TKey key, [MaybeNullWhen(false)] out TValue value)
#else
public bool TryRemove(TKey key, out TValue value)
#endif
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
value = default;
return _table.RemoveIfMatch(key, ref value, ValueMatch.NotNullOrDead);
}
/// <summary>Removes a key and value from the dictionary.</summary>
/// <param name="item">The <see cref="KeyValuePair{TKey,TValue}"/> representing the key and value to remove.</param>
/// <returns>
/// true if the key and value represented by <paramref name="item"/> are successfully
/// found and removed; otherwise, false.
/// </returns>
/// <remarks>
/// Both the specifed key and value must match the entry in the dictionary for it to be removed.
/// The key is compared using the dictionary's comparer (or the default comparer for <typeparamref name="TKey"/>
/// if no comparer was provided to the dictionary when it was constructed). The value is compared using the
/// default comparer for <typeparamref name="TValue"/>.
/// </remarks>
/// <exception cref="ArgumentNullException">
/// The <see cref="KeyValuePair{TKey, TValue}.Key"/> property of <paramref name="item"/> is a null reference.
/// </exception>
public bool TryRemove(KeyValuePair<TKey, TValue> item)
{
if (item.Key is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(item));
}
TValue oldVal = item.Value;
return _table.RemoveIfMatch(item.Key, ref oldVal, ValueMatch.OldValue);
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private TValue FromObjectValue(object obj)
{
// regular value type
if (default(TValue) != null)
{
return Unsafe.As<Boxed<TValue>>(obj).Value;
}
// null
if (obj == NULLVALUE)
{
return default(TValue);
}
// ref type
if (!_valueIsValueType)
{
return Unsafe.As<object, TValue>(ref obj);
}
// nullable
return (TValue)obj;
}
/// <summary>
/// Attempts to get the value associated with the specified key from the <see cref="NonBlockingDictionary{TKey,TValue}"/>.
/// </summary>
/// <param name="key">The key of the value to get.</param>
/// <param name="value">
/// When this method returns, <paramref name="value"/> contains the object from
/// the <see cref="NonBlockingDictionary{TKey,TValue}"/> with the specified key or the default value of
/// <typeparamref name="TValue"/>, if the operation failed.
/// </param>
/// <returns>true if the key was found in the <see cref="NonBlockingDictionary{TKey,TValue}"/>; otherwise, false.</returns>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference (Nothing in Visual Basic).</exception>
#if NETSTANDARD2_1_OR_GREATER || NETCOREAPP
public bool TryGetValue(TKey key, [MaybeNullWhen(false)] out TValue value)
#else
public bool TryGetValue(TKey key, out TValue value)
#endif
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
object oldValObj = _table.TryGetValue(key);
Debug.Assert(!(oldValObj is Prime));
if (oldValObj != null)
{
value = FromObjectValue(oldValObj);
return true;
}
else
{
value = default(TValue);
return false;
}
}
/// <summary>
/// Updates the value associated with <paramref name="key"/> to <paramref name="newValue"/> if the existing value is equal
/// to <paramref name="comparisonValue"/>.
/// </summary>
/// <param name="key">The key whose value is compared with <paramref name="comparisonValue"/> and
/// possibly replaced.</param>
/// <param name="newValue">The value that replaces the value of the element with <paramref
/// name="key"/> if the comparison results in equality.</param>
/// <param name="comparisonValue">The value that is compared to the value of the element with
/// <paramref name="key"/>.</param>
/// <returns>
/// true if the value with <paramref name="key"/> was equal to <paramref name="comparisonValue"/> and
/// replaced with <paramref name="newValue"/>; otherwise, false.
/// </returns>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference.</exception>
public bool TryUpdate(TKey key, TValue newValue, TValue comparisonValue)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
TValue oldVal = comparisonValue;
return _table.PutIfMatch(key, newValue, ref oldVal, ValueMatch.OldValue);
}
/// <summary>
/// Removes all keys and values from the <see cref="NonBlockingDictionary{TKey,TValue}"/>.
/// </summary>
public void Clear() => _table.Clear();
/// <summary>
/// Copies the elements of the <see cref="ICollection{T}"/> to an array of type <see cref="KeyValuePair{TKey,TValue}"/>,
/// starting at the specified array index.
/// </summary>
/// <param name="array">
/// The one-dimensional array of type <see cref="KeyValuePair{TKey,TValue}"/> that is the destination of the <see
/// cref="KeyValuePair{TKey,TValue}"/> elements copied from the <see cref="ICollection"/>. The array must have zero-based indexing.
/// </param>
/// <param name="index">The zero-based index in <paramref name="array"/> at which copying begins.</param>
/// <exception cref="ArgumentNullException"><paramref name="array"/> is a null reference (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="index"/> is less than 0.</exception>
/// <exception cref="ArgumentException">
/// <paramref name="index"/> is equal to or greater than the length of the <paramref name="array"/>. -or- The number of
/// elements in the source <see cref="ICollection"/> is greater than the available space from <paramref name="index"/> to
/// the end of the destination <paramref name="array"/>.
/// </exception>
void ICollection<KeyValuePair<TKey, TValue>>.CopyTo(KeyValuePair<TKey, TValue>[] array, int index)
{
CopyToPairs(array, index);
}
/// <summary>
/// Copies the key and value pairs stored in the <see cref="NonBlockingDictionary{TKey,TValue}"/> to a
/// new array.
/// </summary>
/// <returns>A new array containing a snapshot of key and value pairs copied from the <see cref="NonBlockingDictionary{TKey,TValue}"/>.
/// </returns>
public KeyValuePair<TKey, TValue>[] ToArray()
{
var snapshot = _table.GetSnapshot();
int count = snapshot.Count;
if (count == 0)
{
return Array.Empty<KeyValuePair<TKey, TValue>>();
}
var array = new KeyValuePair<TKey, TValue>[count];
int idx = 0;
while (snapshot.MoveNext() && idx < array.Length)
{
array[idx++] = snapshot.Current;
}
if (idx != array.Length)
{
Array.Resize(ref array, idx);
}
return array;
}
/// <summary>Copy dictionary contents to an array.</summary>
private void CopyToPairs(KeyValuePair<TKey, TValue>[] array, int index)
{
if (array is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(array));
}
if (index < 0)
{
throw new ArgumentOutOfRangeException(nameof(index));
}
var length = array.Length;
if (index > length)
{
throw new ArgumentException("array is too short");
}
foreach (var entry in this)
{
if ((uint)index < (uint)length)
{
array[index++] = entry;
}
else
{
throw new ArgumentException("array is too short");
}
}
}
/// <summary>Copy dictionary contents to an array.</summary>
private void CopyToEntries(DictionaryEntry[] array, int index)
{
if (array is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(array));
}
if (index < 0)
{
throw new ArgumentOutOfRangeException(nameof(index));
}
var length = array.Length;
if (index >= length)
{
throw new ArgumentException("array is too short");
}
foreach (var entry in this)
{
if ((uint)index < (uint)length)
{
array[index++] = new DictionaryEntry(entry.Key, entry.Value);
}
else
{
throw new ArgumentException("array is too short");
}
}
}
/// <summary>Copy dictionary contents to an array.</summary>
private void CopyToObjects(object[] array, int index)
{
if (array is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(array));
}
if (index < 0)
{
throw new ArgumentOutOfRangeException(nameof(index));
}
var length = array.Length;
if (index > length)
{
throw new ArgumentException("array is too short");
}
foreach (var entry in this)
{
if ((uint)index < (uint)length)
{
array[index++] = entry;
}
else
{
throw new ArgumentException("array is too short");
}
}
}
/// <summary>Returns an enumerator that iterates through the <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>.</summary>
/// <returns>An enumerator for the <see cref="NonBlockingDictionary{TKey,TValue}"/>.</returns>
/// <remarks>
/// The enumerator returned from the dictionary is safe to use concurrently with
/// reads and writes to the dictionary, however it does not represent a moment-in-time snapshot
/// of the dictionary. The contents exposed through the enumerator may contain modifications
/// made to the dictionary after <see cref="GetEnumerator"/> was called.
/// </remarks>
public IEnumerator<KeyValuePair<TKey, TValue>> GetEnumerator()
{
return new SnapshotEnumerator(_table.GetSnapshot());
}
/// <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>
/// <value>
/// The value associated with the specified key. If the specified key is not found, a get operation throws a
/// <see cref="KeyNotFoundException"/>, and a set operation creates a new element with the specified key.
/// </value>
/// <exception cref="ArgumentNullException">
/// <paramref name="key"/> is a null reference (Nothing in Visual Basic).
/// </exception>
/// <exception cref="KeyNotFoundException">
/// The property is retrieved and <paramref name="key"/> does not exist in the collection.
/// </exception>
public TValue this[TKey key]
{
get
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
object oldValObj = _table.TryGetValue(key);
Debug.Assert(oldValObj is not Prime);
return oldValObj != null
? FromObjectValue(oldValObj)
: ThrowKeyNotFoundException();
}
set
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
TValue oldVal = default;
_table.PutIfMatch(key, value, ref oldVal, ValueMatch.Any);
}
}
/// <summary>Throws a KeyNotFoundException.</summary>
/// <remarks>Separate from ThrowHelper to avoid boxing at call site while reusing this generic instantiation.</remarks>
#if NETSTANDARD2_1_OR_GREATER || NETCOREAPP
[DoesNotReturn]
#endif
private static TValue ThrowKeyNotFoundException() =>
throw new KeyNotFoundException();
/// <summary>
/// Gets the <see cref="IEqualityComparer{TKey}" />
/// that is used to determine equality of keys for the dictionary.
/// </summary>
/// <value>
/// The <see cref="IEqualityComparer{TKey}" /> generic interface implementation
/// that is used to determine equality of keys for the current
/// <see cref="NonBlockingDictionary{TKey, TValue}" /> and to provide hash values for the keys.
/// </value>
/// <remarks>
/// <see cref="NonBlockingDictionary{TKey, TValue}" /> requires an equality implementation to determine
/// whether keys are equal. You can specify an implementation of the <see cref="IEqualityComparer{TKey}" />
/// generic interface by using a constructor that accepts a comparer parameter;
/// if you do not specify one, the default generic equality comparer <see cref="EqualityComparer{TKey}.Default" /> is used.
/// </remarks>
public IEqualityComparer<TKey> Comparer => _table._keyComparer ?? EqualityComparer<TKey>.Default;
/// <summary>
/// Gets the number of key/value pairs contained in the <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>.
/// </summary>
/// <exception cref="OverflowException">The dictionary contains too many
/// elements.</exception>
/// <value>The number of key/value pairs contained in the <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>.</value>
/// <remarks>Count has snapshot semantics and represents the number of items in the <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>
/// at the moment when Count was accessed.</remarks>
public int Count => _table.Count;
/// <summary>
/// Adds a key/value pair to the <see cref="NonBlockingDictionary{TKey,TValue}"/>
/// if the key does not already exist.
/// </summary>
/// <param name="key">The key of the element to add.</param>
/// <param name="valueFactory">The function used to generate a value for the key</param>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentNullException"><paramref name="valueFactory"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="OverflowException">The dictionary contains too many
/// elements.</exception>
/// <returns>The value for the key. This will be either the existing value for the key if the
/// key is already in the dictionary, or the new value for the key as returned by valueFactory
/// if the key was not in the dictionary.</returns>
public TValue GetOrAdd(TKey key, Func<TKey, TValue> valueFactory)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
if (valueFactory is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(valueFactory));
}
return _table.GetOrAdd(key, valueFactory);
}
/// <summary>
/// Adds a key/value pair to the <see cref="NonBlockingDictionary{TKey,TValue}"/>
/// if the key does not already exist.
/// </summary>
/// <param name="key">The key of the element to add.</param>
/// <param name="valueFactory">The function used to generate a value for the key</param>
/// <param name="factoryArgument">An argument value to pass into <paramref name="valueFactory"/>.</param>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentNullException"><paramref name="valueFactory"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="OverflowException">The dictionary contains too many
/// elements.</exception>
/// <returns>The value for the key. This will be either the existing value for the key if the
/// key is already in the dictionary, or the new value for the key as returned by valueFactory
/// if the key was not in the dictionary.</returns>
public TValue GetOrAdd<TArg>(TKey key, Func<TKey, TArg, TValue> valueFactory, TArg factoryArgument)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
if (valueFactory is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(valueFactory));
}
object oldValObj = _table.TryGetValue(key);
Debug.Assert(!(oldValObj is Prime));
if (oldValObj != null)
{
return FromObjectValue(oldValObj);
}
else
{
TValue newValue = valueFactory(key, factoryArgument);
TValue oldVal = default;
if (_table.PutIfMatch(key, newValue, ref oldVal, ValueMatch.NullOrDead))
{
return newValue;
}
else
{
return oldVal;
}
}
}
/// <summary>
/// Adds a key/value pair to the <see cref="NonBlockingDictionary{TKey,TValue}"/>
/// if the key does not already exist.
/// </summary>
/// <param name="key">The key of the element to add.</param>
/// <param name="value">the value to be added, if the key does not already exist</param>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="OverflowException">The dictionary contains too many
/// elements.</exception>
/// <returns>The value for the key. This will be either the existing value for the key if the
/// key is already in the dictionary, or the new value if the key was not in the dictionary.</returns>
public TValue GetOrAdd(TKey key, TValue value)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
TValue oldVal = default;
if (_table.PutIfMatch(key, value, ref oldVal, ValueMatch.NullOrDead))
{
return value;
}
return oldVal;
}
/// <summary>
/// Adds a key/value pair to the <see cref="NonBlockingDictionary{TKey,TValue}"/> if the key does not already
/// exist, or updates a key/value pair in the <see cref="NonBlockingDictionary{TKey,TValue}"/> if the key
/// already exists.
/// </summary>
/// <param name="key">The key to be added or whose value should be updated</param>
/// <param name="addValueFactory">The function used to generate a value for an absent key</param>
/// <param name="updateValueFactory">The function used to generate a new value for an existing key
/// based on the key's existing value</param>
/// <param name="factoryArgument">An argument to pass into <paramref name="addValueFactory"/> and <paramref name="updateValueFactory"/>.</param>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentNullException"><paramref name="addValueFactory"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentNullException"><paramref name="updateValueFactory"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="OverflowException">The dictionary contains too many
/// elements.</exception>
/// <returns>The new value for the key. This will be either be the result of addValueFactory (if the key was
/// absent) or the result of updateValueFactory (if the key was present).</returns>
public TValue AddOrUpdate<TArg>(
TKey key, Func<TKey, TArg, TValue> addValueFactory, Func<TKey, TValue, TArg, TValue> updateValueFactory, TArg factoryArgument)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
if (addValueFactory is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(addValueFactory));
}
if (updateValueFactory is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(updateValueFactory));
}
TValue tValue2;
while (true)
{
TValue tValue;
if (this.TryGetValue(key, out tValue))
{
tValue2 = updateValueFactory(key, tValue, factoryArgument);
if (this.TryUpdate(key, tValue2, tValue))
{
return tValue2;
}
}
else
{
tValue2 = addValueFactory(key, factoryArgument);
if (this.TryAdd(key, tValue2))
{
return tValue2;
}
}
}
}
/// <summary>
/// Adds a key/value pair to the <see cref="NonBlockingDictionary{TKey,TValue}"/> if the key does not already
/// exist, or updates a key/value pair in the <see cref="NonBlockingDictionary{TKey,TValue}"/> if the key
/// already exists.
/// </summary>
/// <param name="key">The key to be added or whose value should be updated</param>
/// <param name="addValueFactory">The function used to generate a value for an absent key</param>
/// <param name="updateValueFactory">The function used to generate a new value for an existing key
/// based on the key's existing value</param>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentNullException"><paramref name="addValueFactory"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentNullException"><paramref name="updateValueFactory"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="OverflowException">The dictionary contains too many
/// elements.</exception>
/// <returns>The new value for the key. This will be either the result of addValueFactory (if the key was
/// absent) or the result of updateValueFactory (if the key was present).</returns>
public TValue AddOrUpdate(TKey key, Func<TKey, TValue> addValueFactory, Func<TKey, TValue, TValue> updateValueFactory)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
if (addValueFactory is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(addValueFactory));
}
if (updateValueFactory is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(updateValueFactory));
}
TValue tValue2;
while (true)
{
TValue tValue;
if (this.TryGetValue(key, out tValue))
{
tValue2 = updateValueFactory(key, tValue);
if (this.TryUpdate(key, tValue2, tValue))
{
break;
}
}
else
{
tValue2 = addValueFactory(key);
if (this.TryAdd(key, tValue2))
{
break;
}
}
}
return tValue2;
}
/// <summary>
/// Adds a key/value pair to the <see cref="NonBlockingDictionary{TKey,TValue}"/> if the key does not already
/// exist, or updates a key/value pair in the <see cref="NonBlockingDictionary{TKey,TValue}"/> if the key
/// already exists.
/// </summary>
/// <param name="key">The key to be added or whose value should be updated</param>
/// <param name="addValue">The value to be added for an absent key</param>
/// <param name="updateValueFactory">The function used to generate a new value for an existing key based on
/// the key's existing value</param>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentNullException"><paramref name="updateValueFactory"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="OverflowException">The dictionary contains too many
/// elements.</exception>
/// <returns>The new value for the key. This will be either the value of addValue (if the key was
/// absent) or the result of updateValueFactory (if the key was present).</returns>
public TValue AddOrUpdate(TKey key, TValue addValue, Func<TKey, TValue, TValue> updateValueFactory)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
if (updateValueFactory is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(updateValueFactory));
}
TValue tValue2;
while (true)
{
TValue tValue;
if (this.TryGetValue(key, out tValue))
{
tValue2 = updateValueFactory(key, tValue);
if (this.TryUpdate(key, tValue2, tValue))
{
return tValue2;
}
}
else if (this.TryAdd(key, addValue))
{
return addValue;
}
}
}
/// <summary>
/// Gets a value that indicates whether the <see cref="NonBlockingDictionary{TKey,TValue}"/> is empty.
/// </summary>
/// <value>true if the <see cref="NonBlockingDictionary{TKey,TValue}"/> is empty; otherwise,
/// false.</value>
public bool IsEmpty => _table.Count == 0;
#region IDictionary<TKey,TValue> members
/// <summary>
/// Adds the specified key and value to the <see
/// cref="IDictionary{TKey,TValue}"/>.
/// </summary>
/// <param name="key">The object to use as the key of the element to add.</param>
/// <param name="value">The object to use as the value of the element to add.</param>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="OverflowException">The dictionary contains too many
/// elements.</exception>
/// <exception cref="ArgumentException">
/// An element with the same key already exists in the <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>.</exception>
void IDictionary<TKey, TValue>.Add(TKey key, TValue value)
{
if (!TryAdd(key, value))
{
throw new ArgumentException("duplicate key");
}
}
/// <summary>
/// Removes the element with the specified key from the <see
/// cref="IDictionary{TKey,TValue}"/>.
/// </summary>
/// <param name="key">The key of the element to remove.</param>
/// <returns>true if the element is successfully remove; otherwise false. This method also returns
/// false if
/// <paramref name="key"/> was not found in the original <see
/// cref="IDictionary{TKey,TValue}"/>.
/// </returns>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
bool IDictionary<TKey, TValue>.Remove(TKey key) => TryRemove(key, out _);
/// <summary>
/// Gets a collection containing the keys in the <see
/// cref="Dictionary{TKey,TValue}"/>.
/// </summary>
/// <value>An <see cref="ICollection{TKey}"/> containing the keys in the
/// <see cref="Dictionary{TKey,TValue}"/>.</value>
public ICollection<TKey> Keys => GetKeys();
/// <summary>
/// Gets an <see cref="IEnumerable{TKey}"/> containing the keys of
/// the <see cref="IReadOnlyDictionary{TKey,TValue}"/>.
/// </summary>
/// <value>An <see cref="IEnumerable{TKey}"/> containing the keys of
/// the <see cref="IReadOnlyDictionary{TKey,TValue}"/>.</value>
IEnumerable<TKey> IReadOnlyDictionary<TKey, TValue>.Keys => GetKeys();
/// <summary>
/// Gets a collection containing the values in the <see
/// cref="Dictionary{TKey,TValue}"/>.
/// </summary>
/// <value>An <see cref="ICollection{TValue}"/> containing the values in
/// the
/// <see cref="Dictionary{TKey,TValue}"/>.</value>
public ICollection<TValue> Values => GetValues();
/// <summary>
/// Gets an <see cref="IEnumerable{TValue}"/> containing the values
/// in the <see cref="IReadOnlyDictionary{TKey,TValue}"/>.
/// </summary>
/// <value>An <see cref="IEnumerable{TValue}"/> containing the
/// values in the <see cref="IReadOnlyDictionary{TKey,TValue}"/>.</value>
IEnumerable<TValue> IReadOnlyDictionary<TKey, TValue>.Values => GetValues();
#endregion
#region ICollection<KeyValuePair<TKey,TValue>> Members
/// <summary>
/// Adds the specified value to the <see cref="ICollection{TValue}"/>
/// with the specified key.
/// </summary>
/// <param name="keyValuePair">The <see cref="KeyValuePair{TKey,TValue}"/>
/// structure representing the key and value to add to the <see
/// cref="Dictionary{TKey,TValue}"/>.</param>
/// <exception cref="ArgumentNullException">The <paramref name="keyValuePair"/> of <paramref
/// name="keyValuePair"/> is null.</exception>
/// <exception cref="OverflowException">The <see
/// cref="Dictionary{TKey,TValue}"/>
/// contains too many elements.</exception>
/// <exception cref="ArgumentException">An element with the same key already exists in the
/// <see cref="Dictionary{TKey,TValue}"/></exception>
void ICollection<KeyValuePair<TKey, TValue>>.Add(KeyValuePair<TKey, TValue> keyValuePair) => ((IDictionary<TKey, TValue>)this).Add(keyValuePair.Key, keyValuePair.Value);
/// <summary>
/// Determines whether the <see cref="ICollection{T}"/>
/// contains a specific key and value.
/// </summary>
/// <param name="keyValuePair">The <see cref="KeyValuePair{TKey,TValue}"/>
/// structure to locate in the <see
/// cref="ICollection{TValue}"/>.</param>
/// <returns>true if the <paramref name="keyValuePair"/> is found in the <see
/// cref="ICollection{T}"/>; otherwise, false.</returns>
bool ICollection<KeyValuePair<TKey, TValue>>.Contains(KeyValuePair<TKey, TValue> keyValuePair)
{
TValue value;
return TryGetValue(keyValuePair.Key, out value) &&
EqualityComparer<TValue>.Default.Equals(value, keyValuePair.Value);
}
/// <summary>
/// Gets a value indicating whether the dictionary is read-only.
/// </summary>
/// <value>true if the <see cref="ICollection{T}"/> is
/// read-only; otherwise, false. For <see
/// cref="Dictionary{TKey,TValue}"/>, this property always returns
/// false.</value>
bool ICollection<KeyValuePair<TKey, TValue>>.IsReadOnly => false;
/// <summary>
/// Removes a key and value from the dictionary.
/// </summary>
/// <param name="keyValuePair">The <see
/// cref="KeyValuePair{TKey,TValue}"/>
/// structure representing the key and value to remove from the <see
/// cref="Dictionary{TKey,TValue}"/>.</param>
/// <returns>true if the key and value represented by <paramref name="keyValuePair"/> is successfully
/// found and removed; otherwise, false.</returns>
/// <exception cref="ArgumentNullException">The Key property of <paramref
/// name="keyValuePair"/> is a null reference (Nothing in Visual Basic).</exception>
bool ICollection<KeyValuePair<TKey, TValue>>.Remove(KeyValuePair<TKey, TValue> keyValuePair) =>
TryRemove(keyValuePair);
#endregion
#region IEnumerable Members
/// <summary>Returns an enumerator that iterates through the <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>.</summary>
/// <returns>An enumerator for the <see cref="NonBlockingDictionary{TKey,TValue}"/>.</returns>
/// <remarks>
/// The enumerator returned from the dictionary is safe to use concurrently with
/// reads and writes to the dictionary, however it does not represent a moment-in-time snapshot
/// of the dictionary. The contents exposed through the enumerator may contain modifications
/// made to the dictionary after <see cref="GetEnumerator"/> was called.
/// </remarks>
IEnumerator IEnumerable.GetEnumerator() => ((NonBlockingDictionary<TKey, TValue>)this).GetEnumerator();
#endregion
#region IDictionary Members
/// <summary>
/// Adds the specified key and value to the dictionary.
/// </summary>
/// <param name="key">The object to use as the key.</param>
/// <param name="value">The object to use as the value.</param>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="OverflowException">The dictionary contains too many
/// elements.</exception>
/// <exception cref="ArgumentException">
/// <paramref name="key"/> is of a type that is not assignable to the key type <typeparamref
/// name="TKey"/> of the <see cref="Dictionary{TKey,TValue}"/>. -or-
/// <paramref name="value"/> is of a type that is not assignable to <typeparamref name="TValue"/>,
/// the type of values in the <see cref="Dictionary{TKey,TValue}"/>.
/// -or- A value with the same key already exists in the <see
/// cref="Dictionary{TKey,TValue}"/>.
/// </exception>
void IDictionary.Add(object key, object? value)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
if (!(key is TKey))
{
throw new ArgumentException("type of key is incorrect");
}
ThrowIfInvalidObjectValue(value);
((IDictionary<TKey, TValue>)this).Add((TKey)key, (TValue)value!);
}
/// <summary>
/// Gets whether the <see cref="IDictionary"/> contains an
/// element with the specified key.
/// </summary>
/// <param name="key">The key to locate in the <see
/// cref="IDictionary"/>.</param>
/// <returns>true if the <see cref="IDictionary"/> contains
/// an element with the specified key; otherwise, false.</returns>
/// <exception cref="ArgumentNullException"> <paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
bool IDictionary.Contains(object key)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
return key is TKey tkey && ContainsKey(tkey);
}
/// <summary>Provides an <see cref="IDictionaryEnumerator"/> for the
/// <see cref="IDictionary"/>.</summary>
/// <returns>An <see cref="IDictionaryEnumerator"/> for the <see
/// cref="IDictionary"/>.</returns>
IDictionaryEnumerator IDictionary.GetEnumerator() => new SnapshotIDictionaryEnumerator(_table.GetSnapshot());
/// <summary>
/// Gets a value indicating whether the <see
/// cref="IDictionary"/> has a fixed size.
/// </summary>
/// <value>true if the <see cref="IDictionary"/> has a
/// fixed size; otherwise, false. For <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>, this property always
/// returns false.</value>
bool IDictionary.IsFixedSize => false;
/// <summary>
/// Gets a value indicating whether the <see
/// cref="IDictionary"/> is read-only.
/// </summary>
/// <value>true if the <see cref="IDictionary"/> is
/// read-only; otherwise, false. For <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>, this property always
/// returns false.</value>
bool IDictionary.IsReadOnly => false;
/// <summary>
/// Gets an <see cref="ICollection"/> containing the keys of the <see
/// cref="IDictionary"/>.
/// </summary>
/// <value>An <see cref="ICollection"/> containing the keys of the <see
/// cref="IDictionary"/>.</value>
ICollection IDictionary.Keys => GetKeys();
/// <summary>
/// Removes the element with the specified key from the <see
/// cref="IDictionary"/>.
/// </summary>
/// <param name="key">The key of the element to remove.</param>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
void IDictionary.Remove(object key)
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
if (key is TKey tkey)
{
TryRemove(tkey, out _);
}
}
/// <summary>
/// Gets an <see cref="ICollection"/> containing the values in the <see
/// cref="IDictionary"/>.
/// </summary>
/// <value>An <see cref="ICollection"/> containing the values in the <see
/// cref="IDictionary"/>.</value>
ICollection IDictionary.Values => GetValues();
/// <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>
/// <value>The value associated with the specified key, or a null reference (Nothing in Visual Basic)
/// if <paramref name="key"/> is not in the dictionary or <paramref name="key"/> is of a type that is
/// not assignable to the key type <typeparamref name="TKey"/> of the <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>.</value>
/// <exception cref="ArgumentNullException"><paramref name="key"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentException">
/// A value is being assigned, and <paramref name="key"/> is of a type that is not assignable to the
/// key type <typeparamref name="TKey"/> of the <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>. -or- A value is being
/// assigned, and <paramref name="key"/> is of a type that is not assignable to the value type
/// <typeparamref name="TValue"/> of the <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>
/// </exception>
object? IDictionary.this[object key]
{
get
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
if (key is TKey tkey && TryGetValue(tkey, out TValue? value))
{
return value;
}
return null;
}
set
{
if (key is null)
{
ThrowHelper.ThrowKeyNullException();
}
if (!(key is TKey))
{
throw new ArgumentException("type of key is incorrect");
}
ThrowIfInvalidObjectValue(value);
((NonBlockingDictionary<TKey, TValue>)this)[(TKey)key] = (TValue)value!;
}
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static void ThrowIfInvalidObjectValue(object? value)
{
if (value != null)
{
if (!(value is TValue))
{
ThrowHelper.ThrowValueNullException();
}
}
else if (default(TValue) != null)
{
ThrowHelper.ThrowValueNullException();
}
}
#endregion
#region ICollection Members
/// <summary>
/// Copies the elements of the <see cref="ICollection"/> to an array, starting
/// at the specified array index.
/// </summary>
/// <param name="array">The one-dimensional array that is the destination of the elements copied from
/// the <see cref="ICollection"/>. The array must have zero-based
/// indexing.</param>
/// <param name="index">The zero-based index in <paramref name="array"/> at which copying
/// begins.</param>
/// <exception cref="ArgumentNullException"><paramref name="array"/> is a null reference
/// (Nothing in Visual Basic).</exception>
/// <exception cref="ArgumentOutOfRangeException"><paramref name="index"/> is less than
/// 0.</exception>
/// <exception cref="ArgumentException"><paramref name="index"/> is equal to or greater than
/// the length of the <paramref name="array"/>. -or- The number of elements in the source <see
/// cref="ICollection"/>
/// is greater than the available space from <paramref name="index"/> to the end of the destination
/// <paramref name="array"/>.</exception>
void ICollection.CopyTo(Array array, int index)
{
if (array is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(array));
}
// To be consistent with the behavior of ICollection.CopyTo() in Dictionary<TKey,TValue>,
// we recognize three types of target arrays:
// - an array of KeyValuePair<TKey, TValue> structs
// - an array of DictionaryEntry structs
// - an array of objects
if (array is KeyValuePair<TKey, TValue>[] pairs)
{
CopyToPairs(pairs, index);
return;
}
if (array is DictionaryEntry[] entries)
{
CopyToEntries(entries, index);
return;
}
if (array is object[] objects)
{
CopyToObjects(objects, index);
return;
}
throw new ArgumentException("array type is incorrect", nameof(array));
}
/// <summary>
/// Gets a value indicating whether access to the <see cref="ICollection"/> is
/// synchronized with the SyncRoot.
/// </summary>
/// <value>true if access to the <see cref="ICollection"/> is synchronized
/// (thread safe); otherwise, false. For <see
/// cref="NonBlockingDictionary{TKey,TValue}"/>, this property always
/// returns false.</value>
bool ICollection.IsSynchronized => false;
/// <summary>
/// Gets an object that can be used to synchronize access to the <see
/// cref="ICollection"/>. This property is not supported.
/// </summary>
/// <exception cref="NotSupportedException">The SyncRoot property is not supported.</exception>
object ICollection.SyncRoot => throw new NotSupportedException("SyncRoot not supported");
#endregion
/// <summary>
/// Gets a collection containing the keys in the dictionary.
/// </summary>
private ReadOnlyCollection<TKey> GetKeys()
{
var keys = new List<TKey>(Count);
foreach (var kv in this)
{
keys.Add(kv.Key);
}
return new ReadOnlyCollection<TKey>(keys);
}
/// <summary>
/// Gets a collection containing the values in the dictionary.
/// </summary>
private ReadOnlyCollection<TValue> GetValues()
{
var values = new List<TValue>(Count);
foreach (var kv in this)
{
values.Add(kv.Value);
}
return new ReadOnlyCollection<TValue>(values);
}
internal class SnapshotEnumerator : IEnumerator<KeyValuePair<TKey, TValue>>
{
private DictionaryImpl<TKey, TValue>.Snapshot _snapshot;
public SnapshotEnumerator(DictionaryImpl<TKey, TValue>.Snapshot snapshot)
{
_snapshot = snapshot;
}
public KeyValuePair<TKey, TValue> Current => _snapshot.Current;
object IEnumerator.Current => _snapshot.Current;
public bool MoveNext() => _snapshot.MoveNext();
public void Reset() => _snapshot.Reset();
public void Dispose() { }
}
internal class SnapshotIDictionaryEnumerator : IDictionaryEnumerator
{
private DictionaryImpl<TKey, TValue>.Snapshot _snapshot;
public SnapshotIDictionaryEnumerator(DictionaryImpl<TKey, TValue>.Snapshot snapshot)
{
_snapshot = snapshot;
}
public DictionaryEntry Entry => _snapshot.Entry;
object IEnumerator.Current => _snapshot.Entry;
public object Key => _snapshot.Current.Key;
public object Value => _snapshot.Current.Value;
public bool MoveNext() => _snapshot.MoveNext();
public void Reset() => _snapshot.Reset();
public void Dispose() { }
}
}
internal sealed class IDictionaryDebugView<TKey, TValue> where TKey : notnull
{
private readonly IDictionary<TKey, TValue> _dictionary;
public IDictionaryDebugView(IDictionary<TKey, TValue> dictionary)
{
if (dictionary is null)
{
ThrowHelper.ThrowArgumentNullException(nameof(dictionary));
}
_dictionary = dictionary;
}
[DebuggerBrowsable(DebuggerBrowsableState.RootHidden)]
public KeyValuePair<TKey, TValue>[] Items
{
get
{
var items = new KeyValuePair<TKey, TValue>[_dictionary.Count];
_dictionary.CopyTo(items, 0);
return items;
}
}
}
internal static class ThrowHelper
{
#if NETSTANDARD2_1_OR_GREATER || NETCOREAPP
[DoesNotReturn]
#endif
internal static void ThrowKeyNullException() => ThrowArgumentNullException("key");
#if NETSTANDARD2_1_OR_GREATER || NETCOREAPP
[DoesNotReturn]
#endif
internal static void ThrowArgumentNullException(string name) => throw new ArgumentNullException(name);
#if NETSTANDARD2_1_OR_GREATER || NETCOREAPP
[DoesNotReturn]
#endif
internal static void ThrowArgumentNullException(string name, string message) => throw new ArgumentNullException(name, message);
#if NETSTANDARD2_1_OR_GREATER || NETCOREAPP
[DoesNotReturn]
#endif
internal static void ThrowValueNullException() => throw new ArgumentException("value is null");
#if NETSTANDARD2_1_OR_GREATER || NETCOREAPP
[DoesNotReturn]
#endif
internal static void ThrowOutOfMemoryException() => throw new OutOfMemoryException();
}
}