689 lines
19 KiB
C#
689 lines
19 KiB
C#
/*
|
|
Copyright (c) 2003-2006 Niels Kokholm and Peter Sestoft
|
|
Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
of this software and associated documentation files (the "Software"), to deal
|
|
in the Software without restriction, including without limitation the rights
|
|
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
copies of the Software, and to permit persons to whom the Software is
|
|
furnished to do so, subject to the following conditions:
|
|
|
|
The above copyright notice and this permission notice shall be included in
|
|
all copies or substantial portions of the Software.
|
|
|
|
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
|
|
SOFTWARE.
|
|
*/
|
|
|
|
using System;
|
|
using System.Diagnostics;
|
|
using SCG = System.Collections.Generic;
|
|
|
|
namespace C5
|
|
{
|
|
/// <summary>
|
|
/// A bag collection based on a hash table of (item,count) pairs.
|
|
/// </summary>
|
|
[Serializable]
|
|
public class HashBag<T> : CollectionBase<T>, ICollection<T>
|
|
{
|
|
#region Fields
|
|
HashSet<KeyValuePair<T, int>> dict;
|
|
#endregion
|
|
|
|
#region Events
|
|
|
|
/// <summary>
|
|
///
|
|
/// </summary>
|
|
/// <value></value>
|
|
public override EventTypeEnum ListenableEvents { get { return EventTypeEnum.Basic; } }
|
|
|
|
#endregion
|
|
|
|
#region Constructors
|
|
/// <summary>
|
|
/// Create a hash bag with the deafult item equalityComparer.
|
|
/// </summary>
|
|
public HashBag() : this(EqualityComparer<T>.Default) { }
|
|
|
|
/// <summary>
|
|
/// Create a hash bag with an external item equalityComparer.
|
|
/// </summary>
|
|
/// <param name="itemequalityComparer">The external item equalityComparer.</param>
|
|
public HashBag(SCG.IEqualityComparer<T> itemequalityComparer)
|
|
: base(itemequalityComparer)
|
|
{
|
|
dict = new HashSet<KeyValuePair<T, int>>(new KeyValuePairEqualityComparer<T, int>(itemequalityComparer));
|
|
}
|
|
|
|
/// <summary>
|
|
/// Create a hash bag with external item equalityComparer, prescribed initial table size and default fill threshold (66%)
|
|
/// </summary>
|
|
/// <param name="capacity">Initial table size (rounded to power of 2, at least 16)</param>
|
|
/// <param name="itemequalityComparer">The external item equalityComparer</param>
|
|
public HashBag(int capacity, SCG.IEqualityComparer<T> itemequalityComparer)
|
|
: base(itemequalityComparer)
|
|
{
|
|
dict = new HashSet<KeyValuePair<T, int>>(capacity, new KeyValuePairEqualityComparer<T, int>(itemequalityComparer));
|
|
}
|
|
|
|
|
|
/// <summary>
|
|
/// Create a hash bag with external item equalityComparer, prescribed initial table size and fill threshold.
|
|
/// </summary>
|
|
/// <param name="capacity">Initial table size (rounded to power of 2, at least 16)</param>
|
|
/// <param name="fill">Fill threshold (valid range 10% to 90%)</param>
|
|
/// <param name="itemequalityComparer">The external item equalityComparer</param>
|
|
public HashBag(int capacity, double fill, SCG.IEqualityComparer<T> itemequalityComparer)
|
|
: base(itemequalityComparer)
|
|
{
|
|
dict = new HashSet<KeyValuePair<T, int>>(capacity, fill, new KeyValuePairEqualityComparer<T, int>(itemequalityComparer));
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region IEditableCollection<T> Members
|
|
|
|
/// <summary>
|
|
/// The complexity of the Contains operation
|
|
/// </summary>
|
|
/// <value>Always returns Speed.Constant</value>
|
|
[Tested]
|
|
public virtual Speed ContainsSpeed { [Tested]get { return Speed.Constant; } }
|
|
|
|
/// <summary>
|
|
/// Check if an item is in the bag
|
|
/// </summary>
|
|
/// <param name="item">The item to look for</param>
|
|
/// <returns>True if bag contains item</returns>
|
|
[Tested]
|
|
public virtual bool Contains(T item)
|
|
{ return dict.Contains(new KeyValuePair<T, int>(item, 0)); }
|
|
|
|
|
|
/// <summary>
|
|
/// Check if an item (collection equal to a given one) is in the bag and
|
|
/// if so report the actual item object found.
|
|
/// </summary>
|
|
/// <param name="item">On entry, the item to look for.
|
|
/// On exit the item found, if any</param>
|
|
/// <returns>True if bag contains item</returns>
|
|
[Tested]
|
|
public virtual bool Find(ref T item)
|
|
{
|
|
KeyValuePair<T, int> p = new KeyValuePair<T, int>(item, 0);
|
|
|
|
if (dict.Find(ref p))
|
|
{
|
|
item = p.Key;
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
/// <summary>
|
|
/// Check if an item (collection equal to a given one) is in the bag and
|
|
/// if so replace the item object in the bag with the supplied one.
|
|
/// </summary>
|
|
/// <param name="item">The item object to update with</param>
|
|
/// <returns>True if item was found (and updated)</returns>
|
|
[Tested]
|
|
public virtual bool Update(T item)
|
|
{ T olditem = default(T); return Update(item, out olditem); }
|
|
|
|
|
|
/// <summary>
|
|
///
|
|
/// </summary>
|
|
/// <param name="item"></param>
|
|
/// <param name="olditem"></param>
|
|
/// <returns></returns>
|
|
public virtual bool Update(T item, out T olditem)
|
|
{
|
|
KeyValuePair<T, int> p = new KeyValuePair<T, int>(item, 0);
|
|
|
|
updatecheck();
|
|
|
|
//Note: we cannot just do dict.Update: we have to lookup the count before we
|
|
//know what to update with. There is of course a way around if we use the
|
|
//implementation of hashset -which we do not want to do.
|
|
//The hashbag is moreover mainly a proof of concept
|
|
if (dict.Find(ref p))
|
|
{
|
|
olditem = p.Key;
|
|
p.Key = item;
|
|
dict.Update(p);
|
|
if (ActiveEvents != 0)
|
|
raiseForUpdate(item, olditem, p.Value);
|
|
return true;
|
|
}
|
|
|
|
olditem = default(T);
|
|
return false;
|
|
}
|
|
|
|
|
|
/// <summary>
|
|
/// Check if an item (collection equal to a given one) is in the bag.
|
|
/// If found, report the actual item object in the bag,
|
|
/// else add the supplied one.
|
|
/// </summary>
|
|
/// <param name="item">On entry, the item to look for or add.
|
|
/// On exit the actual object found, if any.</param>
|
|
/// <returns>True if item was found</returns>
|
|
[Tested]
|
|
public virtual bool FindOrAdd(ref T item)
|
|
{
|
|
updatecheck();
|
|
if (Find(ref item))
|
|
return true;
|
|
|
|
Add(item);
|
|
return false;
|
|
}
|
|
|
|
|
|
/// <summary>
|
|
/// Check if an item (collection equal to a supplied one) is in the bag and
|
|
/// if so replace the item object in the set with the supplied one; else
|
|
/// add the supplied one.
|
|
/// </summary>
|
|
/// <param name="item">The item to look for and update or add</param>
|
|
/// <returns>True if item was updated</returns>
|
|
[Tested]
|
|
public virtual bool UpdateOrAdd(T item)
|
|
{
|
|
updatecheck();
|
|
if (Update(item))
|
|
return true;
|
|
|
|
Add(item);
|
|
return false;
|
|
}
|
|
|
|
/// <summary>
|
|
///
|
|
/// </summary>
|
|
/// <param name="item"></param>
|
|
/// <param name="olditem"></param>
|
|
/// <returns></returns>
|
|
public virtual bool UpdateOrAdd(T item, out T olditem)
|
|
{
|
|
updatecheck();
|
|
if (Update(item, out olditem))
|
|
return true;
|
|
|
|
Add(item);
|
|
return false;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Remove one copy af an item from the bag
|
|
/// </summary>
|
|
/// <param name="item">The item to remove</param>
|
|
/// <returns>True if item was (found and) removed </returns>
|
|
[Tested]
|
|
public virtual bool Remove(T item)
|
|
{
|
|
KeyValuePair<T, int> p = new KeyValuePair<T, int>(item, 0);
|
|
|
|
updatecheck();
|
|
if (dict.Find(ref p))
|
|
{
|
|
size--;
|
|
if (p.Value == 1)
|
|
dict.Remove(p);
|
|
else
|
|
{
|
|
p.Value--;
|
|
dict.Update(p);
|
|
}
|
|
if (ActiveEvents != 0)
|
|
raiseForRemove(p.Key);
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
/// <summary>
|
|
/// Remove one copy of an item from the bag, reporting the actual matching item object.
|
|
/// </summary>
|
|
/// <param name="item">The value to remove.</param>
|
|
/// <param name="removeditem">The removed value.</param>
|
|
/// <returns>True if item was found.</returns>
|
|
[Tested]
|
|
public virtual bool Remove(T item, out T removeditem)
|
|
{
|
|
updatecheck();
|
|
KeyValuePair<T, int> p = new KeyValuePair<T, int>(item, 0);
|
|
if (dict.Find(ref p))
|
|
{
|
|
removeditem = p.Key;
|
|
size--;
|
|
if (p.Value == 1)
|
|
dict.Remove(p);
|
|
else
|
|
{
|
|
p.Value--;
|
|
dict.Update(p);
|
|
}
|
|
if (ActiveEvents != 0)
|
|
raiseForRemove(removeditem);
|
|
|
|
return true;
|
|
}
|
|
|
|
removeditem = default(T);
|
|
return false;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Remove all items in a supplied collection from this bag, counting multiplicities.
|
|
/// </summary>
|
|
/// <typeparam name="U"></typeparam>
|
|
/// <param name="items">The items to remove.</param>
|
|
[Tested]
|
|
public virtual void RemoveAll<U>(SCG.IEnumerable<U> items) where U : T
|
|
{
|
|
#warning Improve if items is a counting bag
|
|
updatecheck();
|
|
bool mustRaise = (ActiveEvents & (EventTypeEnum.Changed | EventTypeEnum.Removed)) != 0;
|
|
RaiseForRemoveAllHandler raiseHandler = mustRaise ? new RaiseForRemoveAllHandler(this) : null;
|
|
foreach (U item in items)
|
|
{
|
|
KeyValuePair<T, int> p = new KeyValuePair<T, int>(item, 0);
|
|
if (dict.Find(ref p))
|
|
{
|
|
size--;
|
|
if (p.Value == 1)
|
|
dict.Remove(p);
|
|
else
|
|
{
|
|
p.Value--;
|
|
dict.Update(p);
|
|
}
|
|
if (mustRaise)
|
|
raiseHandler.Remove(p.Key);
|
|
}
|
|
}
|
|
if (mustRaise)
|
|
raiseHandler.Raise();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Remove all items from the bag, resetting internal table to initial size.
|
|
/// </summary>
|
|
[Tested]
|
|
public virtual void Clear()
|
|
{
|
|
updatecheck();
|
|
if (size == 0)
|
|
return;
|
|
dict.Clear();
|
|
int oldsize = size;
|
|
size = 0;
|
|
if ((ActiveEvents & EventTypeEnum.Cleared) != 0)
|
|
raiseCollectionCleared(true, oldsize);
|
|
if ((ActiveEvents & EventTypeEnum.Changed) != 0)
|
|
raiseCollectionChanged();
|
|
}
|
|
|
|
|
|
/// <summary>
|
|
/// Remove all items *not* in a supplied collection from this bag,
|
|
/// counting multiplicities.
|
|
/// </summary>
|
|
/// <typeparam name="U"></typeparam>
|
|
/// <param name="items">The items to retain</param>
|
|
[Tested]
|
|
public virtual void RetainAll<U>(SCG.IEnumerable<U> items) where U : T
|
|
{
|
|
updatecheck();
|
|
|
|
HashBag<T> res = new HashBag<T>(itemequalityComparer);
|
|
|
|
foreach (U item in items)
|
|
{
|
|
KeyValuePair<T, int> p = new KeyValuePair<T, int>(item);
|
|
if (dict.Find(ref p))
|
|
{
|
|
KeyValuePair<T, int> q = p;
|
|
if (res.dict.Find(ref q))
|
|
{
|
|
if (q.Value < p.Value)
|
|
{
|
|
q.Value++;
|
|
res.dict.Update(q);
|
|
res.size++;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
q.Value = 1;
|
|
res.dict.Add(q);
|
|
res.size++;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (size == res.size)
|
|
return;
|
|
|
|
CircularQueue<T> wasRemoved = null;
|
|
if ((ActiveEvents & EventTypeEnum.Removed) != 0)
|
|
{
|
|
wasRemoved = new CircularQueue<T>();
|
|
foreach (KeyValuePair<T, int> p in dict)
|
|
{
|
|
int removed = p.Value - res.ContainsCount(p.Key);
|
|
if (removed > 0)
|
|
#warning We could send bag events here easily using a CircularQueue of (should?)
|
|
for (int i = 0; i < removed; i++)
|
|
wasRemoved.Enqueue(p.Key);
|
|
}
|
|
}
|
|
dict = res.dict;
|
|
size = res.size;
|
|
|
|
if ((ActiveEvents & EventTypeEnum.Removed) != 0)
|
|
raiseForRemoveAll(wasRemoved);
|
|
else if ((ActiveEvents & EventTypeEnum.Changed) != 0)
|
|
raiseCollectionChanged();
|
|
}
|
|
|
|
/// <summary>
|
|
/// Check if all items in a supplied collection is in this bag
|
|
/// (counting multiplicities).
|
|
/// </summary>
|
|
/// <param name="items">The items to look for.</param>
|
|
/// <typeparam name="U"></typeparam>
|
|
/// <returns>True if all items are found.</returns>
|
|
[Tested]
|
|
public virtual bool ContainsAll<U>(SCG.IEnumerable<U> items) where U : T
|
|
{
|
|
HashBag<T> res = new HashBag<T>(itemequalityComparer);
|
|
|
|
foreach (T item in items)
|
|
if (res.ContainsCount(item) < ContainsCount(item))
|
|
res.Add(item);
|
|
else
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
|
|
/// <summary>
|
|
/// Create an array containing all items in this bag (in enumeration order).
|
|
/// </summary>
|
|
/// <returns>The array</returns>
|
|
[Tested]
|
|
public override T[] ToArray()
|
|
{
|
|
T[] res = new T[size];
|
|
int ind = 0;
|
|
|
|
foreach (KeyValuePair<T, int> p in dict)
|
|
for (int i = 0; i < p.Value; i++)
|
|
res[ind++] = p.Key;
|
|
|
|
return res;
|
|
}
|
|
|
|
|
|
/// <summary>
|
|
/// Count the number of times an item is in this set.
|
|
/// </summary>
|
|
/// <param name="item">The item to look for.</param>
|
|
/// <returns>The count</returns>
|
|
[Tested]
|
|
public virtual int ContainsCount(T item)
|
|
{
|
|
KeyValuePair<T, int> p = new KeyValuePair<T, int>(item, 0);
|
|
|
|
if (dict.Find(ref p))
|
|
return p.Value;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/// <summary>
|
|
///
|
|
/// </summary>
|
|
/// <returns></returns>
|
|
public virtual ICollectionValue<T> UniqueItems() { return new DropMultiplicity<T>(dict); }
|
|
|
|
/// <summary>
|
|
///
|
|
/// </summary>
|
|
/// <returns></returns>
|
|
public virtual ICollectionValue<KeyValuePair<T, int>> ItemMultiplicities()
|
|
{
|
|
return new GuardedCollectionValue<KeyValuePair<T, int>>(dict);
|
|
}
|
|
|
|
/// <summary>
|
|
/// Remove all copies of item from this set.
|
|
/// </summary>
|
|
/// <param name="item">The item to remove</param>
|
|
[Tested]
|
|
public virtual void RemoveAllCopies(T item)
|
|
{
|
|
updatecheck();
|
|
|
|
KeyValuePair<T, int> p = new KeyValuePair<T, int>(item, 0);
|
|
|
|
if (dict.Find(ref p))
|
|
{
|
|
size -= p.Value;
|
|
dict.Remove(p);
|
|
if ((ActiveEvents & EventTypeEnum.Removed) != 0)
|
|
raiseItemsRemoved(p.Key, p.Value);
|
|
if ((ActiveEvents & EventTypeEnum.Changed) != 0)
|
|
raiseCollectionChanged();
|
|
}
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region ICollection<T> Members
|
|
|
|
|
|
/// <summary>
|
|
/// Copy the items of this bag to part of an array.
|
|
/// <exception cref="ArgumentOutOfRangeException"/> if i is negative.
|
|
/// <exception cref="ArgumentException"/> if the array does not have room for the items.
|
|
/// </summary>
|
|
/// <param name="array">The array to copy to</param>
|
|
/// <param name="index">The starting index.</param>
|
|
[Tested]
|
|
public override void CopyTo(T[] array, int index)
|
|
{
|
|
if (index < 0 || index + Count > array.Length)
|
|
throw new ArgumentOutOfRangeException();
|
|
|
|
foreach (KeyValuePair<T, int> p in dict)
|
|
for (int j = 0; j < p.Value; j++)
|
|
array[index++] = p.Key;
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region IExtensible<T> Members
|
|
|
|
/// <summary>
|
|
/// Report if this is a set collection.
|
|
/// </summary>
|
|
/// <value>Always true</value>
|
|
[Tested]
|
|
public virtual bool AllowsDuplicates { [Tested] get { return true; } }
|
|
|
|
/// <summary>
|
|
/// By convention this is true for any collection with set semantics.
|
|
/// </summary>
|
|
/// <value>True if only one representative of a group of equal items
|
|
/// is kept in the collection together with the total count.</value>
|
|
public virtual bool DuplicatesByCounting { get { return true; } }
|
|
|
|
/// <summary>
|
|
/// Add an item to this bag.
|
|
/// </summary>
|
|
/// <param name="item">The item to add.</param>
|
|
/// <returns>Always true</returns>
|
|
[Tested]
|
|
public virtual bool Add(T item)
|
|
{
|
|
updatecheck();
|
|
add(ref item);
|
|
if (ActiveEvents != 0)
|
|
raiseForAdd(item);
|
|
return true;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Add an item to this bag.
|
|
/// </summary>
|
|
/// <param name="item">The item to add.</param>
|
|
[Tested]
|
|
void SCG.ICollection<T>.Add(T item)
|
|
{
|
|
Add(item);
|
|
}
|
|
|
|
private void add(ref T item)
|
|
{
|
|
KeyValuePair<T, int> p = new KeyValuePair<T, int>(item, 1);
|
|
if (dict.Find(ref p))
|
|
{
|
|
p.Value++;
|
|
dict.Update(p);
|
|
item = p.Key;
|
|
}
|
|
else
|
|
dict.Add(p);
|
|
size++;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Add the elements from another collection with a more specialized item type
|
|
/// to this collection.
|
|
/// </summary>
|
|
/// <typeparam name="U">The type of items to add</typeparam>
|
|
/// <param name="items">The items to add</param>
|
|
public virtual void AddAll<U>(SCG.IEnumerable<U> items) where U : T
|
|
{
|
|
updatecheck();
|
|
#warning We could easily raise bag events
|
|
bool mustRaiseAdded = (ActiveEvents & EventTypeEnum.Added) != 0;
|
|
CircularQueue<T> wasAdded = mustRaiseAdded ? new CircularQueue<T>() : null;
|
|
bool wasChanged = false;
|
|
foreach (T item in items)
|
|
{
|
|
T jtem = item;
|
|
add(ref jtem);
|
|
wasChanged = true;
|
|
if (mustRaiseAdded)
|
|
wasAdded.Enqueue(jtem);
|
|
}
|
|
if (!wasChanged)
|
|
return;
|
|
if (mustRaiseAdded)
|
|
foreach (T item in wasAdded)
|
|
raiseItemsAdded(item, 1);
|
|
if ((ActiveEvents & EventTypeEnum.Changed) != 0)
|
|
raiseCollectionChanged();
|
|
}
|
|
|
|
#endregion
|
|
|
|
#region IEnumerable<T> Members
|
|
|
|
|
|
/// <summary>
|
|
/// Choose some item of this collection.
|
|
/// </summary>
|
|
/// <exception cref="NoSuchItemException">if collection is empty.</exception>
|
|
/// <returns></returns>
|
|
public override T Choose()
|
|
{
|
|
return dict.Choose().Key;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Create an enumerator for this bag.
|
|
/// </summary>
|
|
/// <returns>The enumerator</returns>
|
|
[Tested]
|
|
public override SCG.IEnumerator<T> GetEnumerator()
|
|
{
|
|
int left;
|
|
int mystamp = stamp;
|
|
|
|
foreach (KeyValuePair<T, int> p in dict)
|
|
{
|
|
left = p.Value;
|
|
while (left > 0)
|
|
{
|
|
if (mystamp != stamp)
|
|
throw new CollectionModifiedException();
|
|
|
|
left--;
|
|
yield return p.Key;
|
|
}
|
|
}
|
|
}
|
|
#endregion
|
|
|
|
#region ICloneable Members
|
|
|
|
/// <summary>
|
|
/// Make a shallow copy of this HashBag.
|
|
/// </summary>
|
|
/// <returns></returns>
|
|
public virtual object Clone()
|
|
{
|
|
//TODO: make sure this
|
|
HashBag<T> clone = new HashBag<T>(dict.Count > 0 ? dict.Count : 1, itemequalityComparer);
|
|
//TODO: make sure this really adds in the counting bag way!
|
|
clone.AddAll(this);
|
|
return clone;
|
|
}
|
|
|
|
#endregion
|
|
|
|
|
|
#region Diagnostics
|
|
/// <summary>
|
|
/// Test internal structure of data (invariants)
|
|
/// </summary>
|
|
/// <returns>True if pass</returns>
|
|
[Tested]
|
|
public virtual bool Check()
|
|
{
|
|
bool retval = dict.Check();
|
|
int count = 0;
|
|
|
|
foreach (KeyValuePair<T, int> p in dict)
|
|
count += p.Value;
|
|
|
|
if (count != size)
|
|
{
|
|
Console.WriteLine("count({0}) != size({1})", count, size);
|
|
retval = false;
|
|
}
|
|
|
|
return retval;
|
|
}
|
|
#endregion
|
|
}
|
|
}
|