Class LiteDictionary

An implementation of IDictionary that is optimal (in terms of both size and speed) for very small sets of data but still works excellently with large sets of data.

Inheritance

object

LiteDictionary

Implements

IDictionary

ICollection

IEnumerable

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.MemberwiseClone()

object.ReferenceEquals(object, object)

object.ToString()

Namespace: Tangosol.Util

Assembly: Coherence.dll

Syntax

public class LiteDictionary : IDictionary, ICollection, IEnumerable

Remarks

This implementation is not thread-safe.

The LiteDictionary implementation switches at runtime between several different sub-implementations for storing the IDictionary of objects, described here:

"empty dictionary" - a dictionary that contains no data;
"single entry" - a reference directly to a single dictionary entry;
"object[]" - a reference to an array of entries; the item limit for this implementation is determined by the THRESHOLD constant;
"delegation" - for more than THRESHOLD items, a dictionary is created to delegate the dictionary management to; sub-classes can override the default delegation class Hashtable by overriding the factory method InstantiateDictionary().

The LiteDictionary implementation supports the null key value.

Constructors

LiteDictionary()

Constructs a LiteDictionary.

Declaration

public LiteDictionary()

LiteDictionary(IDictionary)

Construct a LiteDictionary with the same mappings as the given dictionary.

Declaration

public LiteDictionary(IDictionary dictionary)

Parameters

Type	Name	Description
IDictionary	dictionary	The dictionary whose mappings are to be placed in this dictionary.

Properties

Count

Gets the number of elements contained in this dictionary.

Declaration

public virtual int Count { get; }

Property Value

Type	Description
int	The number of elements contained in this dictionary.

IsEmpty

Gets true if this dictionary contains no key-value mappings.

Declaration

public virtual bool IsEmpty { get; }

Property Value

Type	Description
bool	true if this dictionary contains no key-value mappings.

IsFixedSize

Gets a value indicating whether the IDictionary object has a fixed size.

Declaration

public virtual bool IsFixedSize { get; }

Property Value

Type	Description
bool	Always false for LiteDictionary.

IsReadOnly

Gets a value indicating whether the IDictionary object is read-only.

Declaration

public virtual bool IsReadOnly { get; }

Property Value

Type	Description
bool	Always false for LiteDictionary.

IsSynchronized

Gets a value indicating whether access to the ICollection is synchronized (thread safe).

Declaration

public virtual bool IsSynchronized { get; }

Property Value

Type	Description
bool	Always false for LiteDictionary.

this[object]

Returns the value to which this dictionary maps the specified key.

Declaration

public virtual object this[object key] { get; set; }

Parameters

Type	Name	Description
object	key	The key of the element to get or set.

Property Value

Type	Description
object	The value to which this dictionary maps the specified key, or `null` if the dictionary contains no mapping for this key.

Keys

Gets a collection containing the keys of the LiteDictionary.

Declaration

public virtual ICollection Keys { get; }

Property Value

Type	Description
ICollection	A collection containing the keys of the LiteDictionary.

SyncRoot

Gets an object that can be used to synchronize access to the ICollection.

Declaration

public virtual object SyncRoot { get; }

Property Value

Type	Description
object	An object that can be used to synchronize access to the ICollection">.

Values

Gets a collection containing the values in the LiteDictionary.

Declaration

public virtual ICollection Values { get; }

Property Value

Type	Description
ICollection	A collection containing the values in the LiteDictionary.

Methods

Add(object, object)

Adds an element with the provided key and value to the IDictionary object.

Declaration

public virtual void Add(object key, object value)

Parameters

Type	Name	Description
object	key	The object to use as the key of the element to add.
object	value	The object to use as the value of the element to add.

CheckShrinkFromOther()

After a mutation operation has reduced the size of an underlying dictionary, check if the delegation model should be replaced with a more size-efficient storage approach, and switch accordingly.

Declaration

protected virtual void CheckShrinkFromOther()

Clear()

Removes all elements from the dictionary.

Declaration

public virtual void Clear()

Contains(object)

Returns true if this dictionary contains a mapping for the specified key.

Declaration

public virtual bool Contains(object key)

Parameters

Type	Name	Description
object	key	The key to locate in the dictionary.

Returns

Type	Description
bool	true if this dictionary contains a mapping for the specified key, false otherwise.

CopyTo(Array, int)

Copies the elements of the ICollection to an Array, starting at a particular index.

Declaration

public virtual void CopyTo(Array array, int index)

Parameters

Type	Name	Description
Array	array	The one-dimensional Array that is the destination of the elements copied from ICollection.
int	index	The zero-based index in array at which copying begins.

GetEnumerator()

Returns an IEnumerator object for this LiteDictionary.

Declaration

public virtual IEnumerator GetEnumerator()

Returns

Type	Description
IEnumerator	An IEnumerator object for this LiteDictionary.

InstantiateDictionary()

Instantiate an IDictionary object to store entries in once the "lite" threshold has been exceeded.

Declaration

protected virtual IDictionary InstantiateDictionary()

Returns

Type	Description
IDictionary	An instance of IDictionary.

InstantiateEntry(object, object)

Instantiate a DictionaryEntry.

Declaration

protected virtual DictionaryEntry InstantiateEntry(object key, object value)

Parameters

Type	Name	Description
object	key	The key.
object	value	The value.

Returns

Type	Description
DictionaryEntry	An instance of DictionaryEntry.

Remove(object)

Removes the mapping for this key from this dictionary if present.

Declaration

public virtual void Remove(object key)

Parameters

Type	Name	Description
object	key	The key of the element to remove.

RemoveEx(object)

Removes the mapping for this key from this map if present.

Declaration

public virtual object RemoveEx(object key)

Parameters

Type	Name	Description
object	key	The key of the element to remove.

Returns

Type	Description
object	Previous value associated with specified key, or `null` if there was no mapping for key. A `null` return can also indicate that the dictionary previously associated `null` with the specified key, if the implementation supports `null` values.

Remarks

Expensive: updates both the underlying cache and the local cache.

Implements

IDictionary

ICollection

IEnumerable