RPtrHashSet Class Reference

#include <e32hashtab.h>

class RPtrHashSet : public RHashTableBase

Inherits from

RPtrHashSet
- RHashTableBase

Public Member Type Definitions
typedef	TPtrHashSetIter< T > TIter

Public Member Functions
	RPtrHashSet(const THashFunction32< T > &, const TIdentityRelation< T > &)
	RPtrHashSet()
void	Close()
TInt	Count()
const T *	Find(const T &)
T *	Find(const T &)
const T &	FindL(const T &)
T &	FindL(const T &)
TInt	Insert(const T *)
void	InsertL(const T *)
TInt	Remove(const T *)
TInt	Reserve(TInt)
void	ReserveL(TInt)
void	ResetAndDestroy()

Inherited Enumerations
	RHashTableBase:TDefaultSpecifier
	RHashTableBase:TElementState

Inherited Functions
	RHashTableBase::ConsistencyCheck(TUint32 ,TUint32 ,TUint32,TUint32 *)
	RHashTableBase::Find(const TAny *,TInt)const
	RHashTableBase::FindL(const TAny *,TInt)const
	RHashTableBase::Insert(const TAny ,TAny &)
	RHashTableBase::PtrInsert(const TAny ,const TAny )
	RHashTableBase::PtrInsertL(const TAny ,const TAny )
	RHashTableBase::RHashTableBase(TGeneralHashFunction32,TGeneralIdentityRelation,TInt,TInt)
	RHashTableBase::Remove(const TAny *)
	RHashTableBase::ValueInsert(const TAny ,TInt,const TAny ,TInt,TInt)
	RHashTableBase::ValueInsertL(const TAny ,TInt,const TAny ,TInt,TInt)

Detailed Description

A templated class which implements an unordered extensional set of objects of type T using a probe-sequence hash table. The objects are not copied into the set when they are added; rather the set stores pointers to the contained objects.

Member Type Definition Documentation

Typedef TIter

typedef TPtrHashSetIter< T >

TIter

A class which allows iteration over the elements of a RPtrHashSet<T> class.

The set being iterated over may not be modified while an iteration is in progress or the iteration operations may malfunction or panic.

Constructor & Destructor Documentation

RPtrHashSet ( const THashFunction32< T > &, const TIdentityRelation< T > & )

RPtrHashSet	(	const THashFunction32< T > &	aHash,
		const TIdentityRelation< T > &	aIdentity
	)	[inline]

Construct a set of objects of type T using a specified hash function and identity relation. The set is initially empty.

Parameters
aHash	The hash function used to hash the objects of type T.
aIdentity	The identity relation used to determine if two objects of type T should be considered identical.

RPtrHashSet ( )

RPtrHashSet

(

)

[inline]

Construct a set of objects of type T using a default hash function and identity relation. The set is initially empty.

Member Function Documentation

Close ( )

void

(

)

[inline]

Reimplemented from RHashTableBase::Close()

Free all memory used by this set. Returns the set to the same state it had following construction.

Count ( )

TInt

Count

(

)

const [inline]

Reimplemented from RHashTableBase::Count()const

Query the number of elements in the set.

Return Value: The number of elements currently in the set.

Find ( const T & )

const T *

Find

(

const T &

aKey

)

const [inline]

Locate a specified element in the set.

Parameters
aKey	The object of type T to search for.

Return Value: A pointer to the specified object, if it is in the set. The object may not be modified via this pointer. NULL if the specified object is not a member of this set.

Find ( const T & )

T *

Find

(

const T &

aKey

)

[inline]

Locate a specified element in the set.

Parameters
aKey	The object of type T to search for.

Return Value: A pointer to the specified object, if it is in the set. The object may be modified via this pointer. Care should be taken not to modify any parts of the object which are used by either the hash function or the identity relation for this set. If this is done the set may become inconsistent, resulting in malfunctions and/or panics at a later time. NULL if the specified object is not a member of this set.

FindL ( const T & )

const T &

FindL

(

const T &

aKey

)

const [inline]

Locate a specified element in the set.

Parameters
aKey	The object of type T to search for.

Return Value: A reference to the specified object, if it is in the set. The object may not be modified via this reference.

Leave Codes
KErrNotFound	if the specified object is not a member of this set.

FindL ( const T & )

T &

FindL

(

const T &

aKey

)

[inline]

Locate a specified element in the set.

Parameters
aKey	The object of type T to search for.

Return Value: A reference to the specified object, if it is in the set. The object may be modified via this reference. Care should be taken not to modify any parts of the object which are used by either the hash function or the identity relation for this set. If this is done the set may become inconsistent, resulting in malfunctions and/or panics at a later time.

Leave Codes
KErrNotFound	if the specified object is not a member of this set.

Insert ( const T * )

TInt

Insert

(

const T *

aKey

)

[inline]

Insert an element into the set.

If the specified object is not currently a member of the set, a pointer to the object is added to the set and KErrNone is returned. If the specified object is currently a member of the set, the existing pointer to the object is replaced by the provided pointer and KErrNone is returned. In both cases only a pointer to the object is stored - the object is never copied.

Parameters
aKey	A pointer to the object of type T to add to the set.

Return Value: KErrNone if the object was added successfully. KErrNoMemory if memory could not be allocated to store the pointer to the new object.

InsertL ( const T * )

void

InsertL

(

const T *

aKey

)

[inline]

Insert an element into the set.

Parameters
aKey	A pointer to the object of type T to add to the set.

Leave Codes
KErrNoMemory	if memory could not be allocated to store the pointer to the new object.

Remove ( const T * )

TInt

Remove

(

const T *

aKey

)

[inline]

Remove an element from the set.

Parameters
aKey	A pointer to the object to be removed.

Return Value: KErrNone if the object was removed successfully. KErrNotFound if the object was not present in the set.

Reserve ( TInt )

TInt

Reserve

(

TInt

aCount

)

[inline]

Reimplemented from RHashTableBase::Reserve(TInt)

Expand the set to accommodate a specified number of elements. If the set already has enough space for the specified number of elements, no action is taken. Any elements already in the set are retained.

Parameters
aCount	The number of elements for which space should be allocated.

Return Value: KErrNone if the operation completed successfully. KErrNoMemory if sufficient memory could not be allocated.

ReserveL ( TInt )

void

ReserveL

(

TInt

aCount

)

[inline]

Reimplemented from RHashTableBase::ReserveL(TInt)

Parameters
aCount	The number of elements for which space should be allocated.

Leave Codes
KErrNoMemory	if sufficient memory could not be allocated.

ResetAndDestroy ( )

void

ResetAndDestroy

(

)

Deletes all the objects of type T to which pointers are stored in this set. Then frees all the memory used by the set and returns the set to the same state as immediately following construction.

Inherited Functions
	RHashTableBase::ConsistencyCheck(TUint32 ,TUint32 ,TUint32,TUint32 *)
	RHashTableBase::Find(const TAny *,TInt)const
	RHashTableBase::FindL(const TAny *,TInt)const
	RHashTableBase::Insert(const TAny ,TAny &)
	RHashTableBase::PtrInsert(const TAny ,const TAny )
	RHashTableBase::PtrInsertL(const TAny ,const TAny )
	RHashTableBase::RHashTableBase(TGeneralHashFunction32,TGeneralIdentityRelation,TInt,TInt)
	RHashTableBase::Remove(const TAny *)
	RHashTableBase::ValueInsert(const TAny ,TInt,const TAny ,TInt,TInt)
	RHashTableBase::ValueInsertL(const TAny ,TInt,const TAny ,TInt,TInt)