SFXHashmap

Class that represents a map utilizing a hash table to achieve high performance in search.

#include <SFXHashmap.h.hpp>

class SFXHashmap;

SFMTYPEDEFCLASS(SFXHashmap)

Inheritance diagram

Collaboration diagram

Description

Each key element of the SFXHashmap instance ( hashmap ) needs to be data not more than 4 bytes, the SFXAnsiString instance, or the SFXWideString instance. In order to process data more than 4 bytes ( such as UInt64 type, Double type, and so on ) or class instance as a value element of the SFXHashmap instance ( hashmap ), a pointer should be used.

// data more than 4 bytes or class instance cannot be a value element of the SFXHashmap instance ( hashmap )

// SFXHashmap<SFXAnsiString, SInt64> map64;          NG
// SFXHashmap<SFXAnsiString, SFXAnsiString> mapstr;  NG

// but a pointer to the data more than 4 bytes or class instance can be a value element of the SFXHashmap instance ( hashmap )

SFXHashmap<SFXAnsiString, SInt64Ptr> map64;             // oK
SFXHashmap<<SFXAnsiString, SFXAnsiStringPtr> mapstr; // oK

Member

Constructor/Destructor
SFXHashmap( `Void` ) Constructor of SFXHashmap class.
SFXHashmap( `UInt16` threshold , `UInt16` ratio ) Constructor of SFXHashmap class.

Public Functions
`Void`	Clear( `Void` ) Clear the hashmap.
`Bool`	ContainsKey( `KeyType` key ) Check whether the specified key element is contained or not.
`Bool`	ContainsValue( `ValueType` value ) Check whether the specified value element is contained or not.
static `SFXHashmap< K, V > const &`	EmptyInstance( `Void` ) Get an empty hashmap.
`Bool`	Equals( `SFXHashmap< K, V > const &` collection ) Check whether to equal the specified hashmap or not.
`ValueType`	Get( `KeyType` key ) Get the value element to match with the specified key.
`KeyEnumerator`	GetKeyEnumerator( `Void` ) Get an enumerator for key elements of hashmap.
`KeyIterator`	GetKeyIterator( `Void` ) Get an iterator for key elements of hashmap.
`UInt16`	GetRatio( `Void` ) Get the expansion ratio of hash table size.
`SInt32`	GetSize( `Void` ) Get the size(the number of key elements of hashmap).
`UInt16`	GetThreshold( `Void` ) Get the threshold to expand the hash table size.
`ValueEnumerator`	GetValueEnumerator( `Void` ) Get an enumerator for value elements of hashmap.
`ValueIterator`	GetValueIterator( `Void` ) Get an iterator for value elements of hashmap.
`Bool`	IsEmpty( `Void` ) Check whether the hashmap is empty or not.
`SFCError`	Merge( `SFXHashmap< K, V > const &` collection ) Merge a hashmap.
`Void`	Remove( `KeyType` key ) Remove the element with the specified key.
`SFCError`	Set( `SFXHashmap< K, V > const &` collection ) Set( `KeyType` key , `ValueType` value ) Set a value element for the specified key. Or set a hashmap.
`Void`	SetRatio( `UInt16` ratio ) Set the expansion ratio of hash table size.
`Void`	SetThreshold( `UInt16` threshold ) Set the threshold to expand the hash table size.
`ValueType`	operator[]( `KeyType` key ) Get the element by index.

Types
DefaultEnum Default values of threshold and ratio to expand the hash table.
KeyEnumerator Class for managing an enumerator for key elements of hashmap.
KeyIterator Class for managing an iterator for key elements of hashmap.
ValueEnumerator Class for managing an enumerator for value elements of hashmap.
ValueIterator Class for managing an iterator for value elements of hashmap.

SFXHashmap::SFXHashmap

Constructor of SFXHashmap class.

[ public, explicit ]
SFXHashmap(Void);

[ public, explicit ]
SFXHashmap(
    UInt16 threshold   // threshold value that expands the hash table
    UInt16 ratio       // ration of hash table expansion
);

SFXHashmap::Clear

Clear the hashmap.

[ public ]
Void Clear(Void);

Description

When using the string key, resource for managing its key is released automatically.

If the type of element is a pointer to a class instance, the instance is not released automatically.

Example

SFXHashmap<SFXAnsiString, SInt32> strmap;
 
...

strmap.Clear();   // release all the data and memory for management

Reference

SFXHashmap::Remove

SFXHashmap::ContainsKey

Check whether the specified key element is contained or not.

[ public, const ]
Bool ContainsKey(
    KeyType key   // key to check
);

Return value

If contained : true
If not contained : false

Example

SFXHashmap<SFXAnsiString, SInt32> strmap;

// set a hashmap element of key and value
if (strmap.Set("mike", 2) == SFERR_NO_ERROR) {
    // set a hashmap element of key and value
    if (strmap.Set("john", 1) == SFERR_NO_ERROR) {
    
        // check whether the key element is contained or not
        TRACE("ContainsKey(\"mike\") = %s", (strmap.ContainsKey("mike")) ? ("true") : ("false"));  // containsKey("mike") = true
        TRACE("ContainsKey(\"tom\") = %s", (strmap.ContainsKey("tom")) ? ("true") : ("false"));    // containsKey("tom") = false
    }
}

Reference

SFXHashmap::ContainsValue

SFXHashmap::ContainsValue

Check whether the specified value element is contained or not.

[ public, const ]
Bool ContainsValue(
    ValueType value   // value to check
);

Return value

If contained : true
If not contained : false

Example

SFXHashmap<SFXAnsiString, SInt32> strmap;

// set a hashmap element of key and value
if (strmap.Set("mike", 2) == SFERR_NO_ERROR) {
    // set a hashmap element of key and value
    if (strmap.Set("john", 1) == SFERR_NO_ERROR) {
    
        // check whether the value element is contained or not
        TRACE("ContainsValue(2) = %s", (strmap.ContainsValue(2)) ? ("true") : ("false"));  // containsValue(2) = true
        TRACE("ContainsValue(5) = %s", (strmap.ContainsValue(5)) ? ("true") : ("false"));  // containsValue(5) = false
    }
}

Reference

SFXHashmap::ContainsKey

SFXHashmap::EmptyInstance

Get an empty hashmap.

[ public, static ]
SFXHashmap< K, V > const & EmptyInstance(Void);

Description

Get an instance that represents an empty hashmap.

SFXHashmap::Equals

Check whether to equal the specified hashmap or not.

[ public, const ]
Bool Equals(
    SFXHashmap< K, V > const & collection   // hashmap to compare with
);

Return value

If equal : true
If not equal : false

Description

Check about two hashmaps whether the same element of key and its value is saved in the same order or not.

If the type of element is a pointer to a class instance, its address is compared.

SFXHashmap::Get

Get the value element to match with the specified key.

[ public, const ]
ValueType Get(
    KeyType key   // key to get the value element
);

Return value

If there is a hashmap element to match with the specified key, rerurn its value element.

If not , return null.

Example

SFXHashmap<SFXAnsiString, SInt32> strmap;

// set a hashmap element of key and value
if (strmap.Set("mike", 2) == SFERR_NO_ERROR) {
    // set a hashmap element of key and value
    if (strmap.Set("john", 1) == SFERR_NO_ERROR) {
    
        // get the value element to match with the specified key
        TRACE("%d", strmap.Get("mike"));  // 2
    }
}

Reference

SFXHashmap::Set

SFXHashmap::GetKeyEnumerator

Get an enumerator for key elements of hashmap.

[ public, const ]
KeyEnumerator GetKeyEnumerator(Void);

Reference

SFXHashmap::GetKeyIterator

Get an iterator for key elements of hashmap.

[ public ]
KeyIterator GetKeyIterator(Void);

Reference

SFXHashmap::GetRatio

Get the expansion ratio of hash table size.

[ public, const ]
UInt16 GetRatio(Void);

Reference

SFXHashmap::SetRatio

SFXHashmap::GetSize

Get the size(the number of key elements of hashmap).

[ public, const ]
SInt32 GetSize(Void);

SFXHashmap::GetThreshold

Get the threshold to expand the hash table size.

[ public, const ]
UInt16 GetThreshold(Void);

Reference

SFXHashmap::SetThreshold

SFXHashmap::GetValueEnumerator

Get an enumerator for value elements of hashmap.

[ public, const ]
ValueEnumerator GetValueEnumerator(Void);

Reference

SFXHashmap::GetValueIterator

Get an iterator for value elements of hashmap.

[ public ]
ValueIterator GetValueIterator(Void);

Reference

SFXHashmap::IsEmpty

Check whether the hashmap is empty or not.

[ public, const ]
Bool IsEmpty(Void);

Return value

If empty : true
If not empty : false

SFXHashmap::Merge

Merge a hashmap.

[ public ]
SFCError Merge(
    SFXHashmap< K, V > const & collection   // hashmap to merge
);

Return value

Success : SFERR_NO_ERROR
If insufficient memory: SFERR_NO_MEMOERY
If failed : SFERR_FAILED

Description

In case an error occurs during processing, the hashmap is restored.

SFXHashmap::Remove

Remove the element with the specified key.

[ public ]
Void Remove(
    KeyType key   // key to remove
);

SFXHashmap::Set

Set a value element for the specified key. Or set a hashmap.

[ public ]
SFCError Set(
    SFXHashmap< K, V > const & collection   // hashmap to set
);

[ public ]
SFCError Set(
    KeyType key       // key to set
    ValueType value   // value to set
);

Return value

Success : SFERR_NO_ERROR
If insufficient memory : SFERR_NO_MEMOERY
If failed : SFERR_FAILED

Description

In case an error occurs during processing, the hashmap is restored.

Example

SFXHashmap<SFXAnsiString, SInt32> strmap;

// set a hashmap element of key and value
if (strmap.Set("mike", 2) == SFERR_NO_ERROR) {
    // set a hashmap element of key and value
    if (strmap.Set("john", 1) == SFERR_NO_ERROR) {
    
        // check whether the key element is contained or not
        TRACE("ContainsKey(\"mike\") = %s", (strmap.ContainsKey("mike")) ? ("true") : ("false"));  // containsKey("mike") = true
        TRACE("ContainsKey(\"tom\") = %s", (strmap.ContainsKey("tom")) ? ("true") : ("false"));    // containsKey("tom") = false
    }
}

Reference

SFXHashmap::Get

SFXHashmap::SetRatio

Set the expansion ratio of hash table size.

[ public ]
Void SetRatio(
    UInt16 ratio   // expansion ratio to set (%)
);

Description

The hash table size is expanded for efficiency when the number of key elements increases.

The expansion ratio of hash table size is specified by percentage.

Reference

SFXHashmap::GetRatio

SFXHashmap::SetThreshold

Set the threshold to expand the hash table size.

[ public ]
Void SetThreshold(
    UInt16 threshold   // threshold ratio to set (%)
);

Description

The hash table size is expanded for efficiency when the number of key elements increases.

The hash table size is automatically expanded when the following condition is satisfied.

(the number of elements) * threshold / 100 > (hash table size)

Reference

SFXHashmap::GetThreshold

SFXHashmap::operator[]

Get the element by index.

[ public, const ]
ValueType operator[](
    KeyType key   // index of element to get
);

Return value

If there is a hashmap element to match with the specified key, rerurn its value element.

If not , return null.

Reference

SFXHashmap::Set

SFXHashmap::DefaultEnum

Default values of threshold and ratio to expand the hash table.

enum DefaultEnum {
    DEFAULT_THRESHOLD = 10,     // default value of threshold to expand the hash table
    DEFAULT_RATIO     = 50      // default value of ratio to expand the hash table
};

Reference

SFXHashmap::SetThreshold | SFXHashmap::GetThreshold | SFXHashmap::SetRatio | SFXHashmap::GetRatio

SFXHashmap::KeyEnumerator

Class for managing an enumerator for key elements of hashmap.

[ public ]

SFMTYPEDEFCLASS(KeyEnumerator)
class KeyEnumerator {
    public:
        explicit            KeyEnumerator           (Void);
                            KeyEnumerator           (KeyIteratorConstRef iterator);
        KeyEnumeratorRef    operator=               (KeyIteratorConstRef iterator);
        KeyType             GetNext                 (Void);
        KeyType             GetPrevious             (Void);
        ValueType           GetValue                (Void) const;
        Bool                HasNext                 (Void) const;
        Bool                HasPrevious             (Void) const;
        Bool                IsValid                 (Void) const;
};

Description

The KeyEnumerator class is a class that manages an enumerator for key elements of hashmap.

The KeyEnumerator class has the following member functions.

GetNext	Get the next element. If no next element, return null.
GetPrevious	Get the previous element. If no previous element, return null.
HasNext	Check whether the next element exists or not.
HasPrevious	Check whether the previous element exists or not.
IsValid	Check whether the enumerator is valid or not.

Reference

SFXHashmap::KeyIterator

Class for managing an iterator for key elements of hashmap.

[ public ]

SFMTYPEDEFCLASS(KeyIterator)
class KeyIterator  {
    public:
        explicit            KeyIterator             (Void);
        KeyType             GetNext                 (Void);
        KeyType             GetPrevious             (Void);
        ValueType           GetValue                (Void) const;
        Bool                HasNext                 (Void) const;
        Bool                HasPrevious             (Void) const;
        Bool                IsValid                 (Void) const;
        Void                Remove                  (Void);
};

Description

The KeyIterator class is a class that manages an iterator for key elements of hashmap.

The KeyIterator class has the following member functions.

GetNext	Get the next element. If no next element, return null.
GetPrevious	Get the previous element. If no previous element, return null.
GetValue	Get the value element of current iterator. If invalid, return null.
HasNext	Check whether the next element exists or not.
HasPrevious	Check whether the previous element exists or not.
IsValid	Check whether the iterator is valid or not.
Remove	Remove the element of current iterator.

Reference

SFXHashmap::ValueEnumerator

Class for managing an enumerator for value elements of hashmap.

[ public ]

SFMTYPEDEFCLASS(ValueEnumerator)
class ValueEnumerator  {
    public:
        explicit            ValueEnumerator         (Void);
                            ValueEnumerator         (ValueIteratorConstRef iterator);
        ValueEnumeratorRef  operator=               (ValueIteratorConstRef iterator);
        ValueType           GetNext                 (Void);
        ValueType           GetPrevious             (Void);
        KeyType             GetKey                  (Void) const;
        Bool                HasNext                 (Void) const;
        Bool                HasPrevious             (Void) const;
        Bool                IsValid                 (Void) const;
};

Description

The ValueEnumerator class is a class that manages an enumerator for value elements of hashmap.

The ValueEnumerator class has the following member functions.

GetNext	Get the next element. If no next element, return null.
GetPrevious	Get the previous element. If no previous element, return null.
HasNext	Check whether the next element exists or not.
HasPrevious	Check whether the previous element exists or not.
IsValid	Check whether the enumerator is valid or not.

Reference

SFXHashmap::ValueIterator

Class for managing an iterator for value elements of hashmap.

[ public ]

SFMTYPEDEFCLASS(ValueIterator)
class ValueIterator  {
    public:
        explicit            ValueIterator           (Void);
        SFCError            Set                     (ValueType value);
        ValueType           GetNext                 (Void);
        ValueType           GetPrevious             (Void);
        KeyType             GetKey                  (Void) const;
        Bool                HasNext                 (Void) const;
        Bool                HasPrevious             (Void) const;
        Bool                IsValid                 (Void) const;
        Void                Remove                  (Void);
};

Description

The ValueIterator class is a class that manages an iterator for value elements of hashmap.

The ValueIterator class has the following member functions.

Set	Set a value to the value element of current iterator.
GetNext	Get the next element. If no next element, return null.
GetPrevious	Get the previous element. If no previous element, return null.
GetKey	Get the key element of current iterator. If invalid, return null.
HasNext	Check whether the next element exists or not.
HasPrevious	Check whether the previous element exists or not.
IsValid	Check whether the iterator is valid or not.
Remove	Remove the element of current iterator.

Reference