RHashMap Class Reference

#include <e32hashtab.h>

class RHashMap : public RHashTableBase

Inherits from

RHashMap
- RHashTableBase

Public Member Type Definitions
typedef	THashMapIter< K, V > TIter

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

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 associative array with key type K and value type V, using a probe-sequence hash table. Both the key and value objects are copied into the table when they are added. A bitwise binary copy is used here, so neither of the types K and V may implement a nontrivial copy constructor.

Member Type Definition Documentation

Typedef TIter

typedef THashMapIter< K, V >

TIter

A class which allows iteration over the elements of a RHashMap<K,V> class.

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

Constructor & Destructor Documentation

RHashMap ( const THashFunction32< K > &, const TIdentityRelation< K > & )

RHashMap	(	const THashFunction32< K > &	aHash,
		const TIdentityRelation< K > &	aIdentity
	)	[inline]

Construct an associative array of key-value pairs of type (K,V) using a specified hash function and identity relation. The array initially contains no key-value pairs.

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

RHashMap ( )

RHashMap

(

)

[inline]

Construct an associative array of key-value pairs of type (K,V) using a default hash function and identity relation. The array initially contains no key-value pairs.

Member Function Documentation

Close ( )

void

(

)

[inline]

Reimplemented from RHashTableBase::Close()

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

Count ( )

TInt

Count

(

)

const [inline]

Reimplemented from RHashTableBase::Count()const

Query the number of key-value pairs in the array.

Return Value: The number of key-value pairs currently in the array.

Find ( const K & )

const V *

Find

(

const K &

aKey

)

const [inline]

Look up a specified key in the associative array and return a pointer to the corresponding value.

Parameters
aKey	The key object of type K to look up.

Return Value: A pointer to the copy of the corresponding value object in the array, if the specified key object was found. The value object may not be modified via this pointer. NULL if the specified key object was not found.

Find ( const K & )

V *

Find

(

const K &

aKey

)

[inline]

Look up a specified key in the associative array and return a pointer to the corresponding value.

Parameters
aKey	The key object of type K to look up.

Return Value: A pointer to the copy of the corresponding value object in the array, if the specified key object was found. The value object may be modified via this pointer. NULL if the specified key object was not found.

FindL ( const K & )

const V &

FindL

(

const K &

aKey

)

const [inline]

Look up a specified key in the associative array and return a pointer to the corresponding value.

Parameters
aKey	The key object of type K to look up.

Return Value: A reference to the copy of the corresponding value object in the array, if the specified key object was found. The value object may not be modified via this reference.

Leave Codes
KErrNotFound	if the specified key object was not found.

FindL ( const K & )

V &

FindL

(

const K &

aKey

)

[inline]

Look up a specified key in the associative array and return a pointer to the corresponding value.

Parameters
aKey	The key object of type K to look up.

Return Value: A reference to the copy of the corresponding value object in the array, if the specified key object was found. The value object may be modified via this reference.

Leave Codes
KErrNotFound	if the specified key object was not found.

Insert ( const K &, const V & )

TInt	Insert	(	const K &	aKey,
			const V &	aValue
		)	[inline]

Insert a key-value pair into the array.

If the specified key object is not found in the array, a copy of the key object along with a copy of the value object are added to the array and KErrNone is returned. If the specified key object is found in the array, the existing copies of both the key and value objects are replaced by the provided objects and KErrNone is returned. In both cases the objects are copied bitwise into the array.

Parameters
aKey	The key object of type K to add to the array.
aValue	The value object of type V to associate with aKey.

Return Value: KErrNone if the key-value pair was added successfully. KErrNoMemory if memory could not be allocated to store the copies of aKey and aValue.

InsertL ( const K &, const V & )

void	InsertL	(	const K &	aKey,
			const V &	aValue
		)	[inline]

Insert a key-value pair into the array.

Parameters
aKey	The key object of type K to add to the array.
aValue	The value object of type V to associate with aKey.

Leave Codes
KErrNoMemory	if memory could not be allocated to store the copies of aKey and aValue.

Remove ( const K & )

TInt

Remove

(

const K &

aKey

)

[inline]

Remove a key-value pair from the array.

Parameters
aKey	The key to be removed.

Return Value: KErrNone if the key object and corresponding value object were removed successfully. KErrNotFound if the key object was not present in the array.

Reserve ( TInt )

TInt

Reserve

(

TInt

aCount

)

[inline]

Reimplemented from RHashTableBase::Reserve(TInt)

Expand the array to accommodate a specified number of key-value pairs. 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 key-value pairs 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 key-value pairs for which space should be allocated.

Leave Codes
KErrNoMemory	if sufficient memory could not be allocated.

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)