Attribute fields data provider: it is a group of attribute stored in {name, value} value pair fasion in a single database table. More...

#include <AttributeProvider.h>

Public Member Functions
	AttributeProvider (void)
	perform test cases when reseting db. More...

bool	IsValid ()
	whether db is opened. More...

void	Cleanup ()
	delete the database and set everything to NULL

DBEntity *	GetDBEntity ()
	get the database object associated with this provider

void	SetDBEntity (const string &sConnectionstring)
	replace the current database with current one. More...

void	ValidateDatabase ()
	ensure that the database has been set up properly. More...

bool	SaveAttributeObject (const char sTableName, IAttributeFields pAttributeObject)
	save the attribute object to the given table More...

bool	LoadAttributeObject (const char sTableName, IAttributeFields pAttributeObject)
	load the attribute object from a given table. More...

void	SetTableName (const char *sName)
	current attribute table name, if the table does not exists it will be created. More...

const string &	GetTableName ()
	current attribute table name More...

bool	ResetTable (const char *sName)
	reset a given table to blank. More...

bool	DoesAttributeExists (const char *sName)
	current object name . More...

bool	GetAttribute (const char *sName, string &sOut)
	get the attribute of the current attribute instance in the current table More...

bool	GetAttribute (CAttributeDbItem &inout)
	get the complete attribute information in the current table More...

bool	InsertAttribute (CAttributeDbItem &sIn)
	insert a new attribute field in the current table More...

bool	InsertAttribute (const char sName, const char sValue)
	insert by simple name value pair More...

bool	UpdateAttribute (const char sName, const char sIn)
	update the attribute of the current attribute instance in the current table insert the attribute if it is not created before. More...

bool	DeleteAttribute (const char *sName)
	delete the attribute of the current attribute instance in the current table More...

bool	CreateTableIfNotExists ()
	create the current table, if it does not exists. More...

Detailed Description

Attribute fields data provider: it is a group of attribute stored in {name, value} value pair fasion in a single database table.

The db table does not define the name, hence a table in the database is very similar to an intance of Iattributefields in ParaEngine. To be extensible, the table record has the following format: {name(prim key), InstanceName(indexed), value, type, description, schematics} in other word, the database table provides a serialization of IAttributeField (all fields are persistent except get/set function address). All instances sharing the same ClassName are usually stored in the same db table. In case of a singleton, we can default InstanceName field to NULL. e.g. game world class may store global information for a game in the database, such as the spawn points, last player position, etc. Besides serializing IAttributeField class, the data provider should also expose methods to add and remove dynamic fields.

Remarks: : Currently, instanced object is not supported. One table only matches to a single object.

Constructor & Destructor Documentation

§ AttributeProvider()

AttributeProvider::AttributeProvider ( void )

perform test cases when reseting db.

Member Function Documentation

§ CreateTableIfNotExists()

bool AttributeProvider::CreateTableIfNotExists ( )

create the current table, if it does not exists.

This function is mostly called automatically when the SetTableName() function is called.

Returns: true if the table exists either created or just the old one.

§ DeleteAttribute()

bool AttributeProvider::DeleteAttribute ( const char * sName )

delete the attribute of the current attribute instance in the current table

Parameters

sName : name of the attribute field

Returns: true if succeed.

§ DoesAttributeExists()

bool AttributeProvider::DoesAttributeExists ( const char * sName )

current object name .

a table may save attribute for multiple objects. this may be empty string, in which case the table is assumed to be storing a singleton object.

Parameters

sName	whether a given attribute exists. This function is usually used internally. One common use of this function is to test if a field exists, so that we know if a object has been saved before or not.
sName	: name of the attribute field

Returns

§ GetAttribute() [1/2]

bool AttributeProvider::GetAttribute	(	const char *	sName,
		string &	sOut
	)

get the attribute of the current attribute instance in the current table

Parameters

sName	: name of the attribute field
sOut	: value of the field as a string.

Returns: true if succeed.

§ GetAttribute() [2/2]

bool AttributeProvider::GetAttribute ( CAttributeDbItem & inout )

get the complete attribute information in the current table

Parameters

inout : [in|out] get the complete database information. CAttributeDbItem::m_sName and CAttributeDbItem::m_sInstanceName must be filled first. the rest of CAttributeDbItem will be filled when the function returns. Please note that if CAttributeDbItem::m_sInstanceName is empty then the current object name will used instead.

Returns: true if succeed.

§ GetTableName()

const string& ParaEngine::AttributeProvider::GetTableName ( )

inline

current attribute table name

Returns: current attribute table name

§ InsertAttribute() [1/2]

bool AttributeProvider::InsertAttribute ( CAttributeDbItem & sIn )

insert a new attribute field in the current table

Parameters

sIn	: [in] CAttributeDbItem::m_sName is always ignored.

Returns: true if succeed.

§ InsertAttribute() [2/2]

bool AttributeProvider::InsertAttribute	(	const char *	sName,
		const char *	sValue
	)

insert by simple name value pair

Parameters

sName
sValue

Returns

§ IsValid()

bool ParaEngine::AttributeProvider::IsValid ( )

inline

whether db is opened.

§ LoadAttributeObject()

bool AttributeProvider::LoadAttributeObject	(	const char *	sTableName,
		IAttributeFields *	pAttributeObject
	)

load the attribute object from a given table.

Parameters

sTableName	if table name is empty, the current table is used.
pAttributeObject	[out]

Returns: true if succeeds

§ ResetTable()

bool AttributeProvider::ResetTable ( const char * sName )

reset a given table to blank.

if the table does not exists a blank one will be created.

Parameters

sName table name

Returns: true if succeeds

§ SaveAttributeObject()

bool AttributeProvider::SaveAttributeObject	(	const char *	sTableName,
		IAttributeFields *	pAttributeObject
	)

save the attribute object to the given table

Parameters

sTableName	if table name is empty, the current table is used.
pAttributeObject	[in]

Returns: true if succeeds

§ SetDBEntity()

void AttributeProvider::SetDBEntity ( const string & sConnectionstring )

replace the current database with current one.

the old one is closed and the new once will be opened.

Parameters

sConnectionstring the file path

§ SetTableName()

void AttributeProvider::SetTableName ( const char * sName )

current attribute table name, if the table does not exists it will be created.

Parameters

sName

§ UpdateAttribute()

bool AttributeProvider::UpdateAttribute	(	const char *	sName,
		const char *	sIn
	)

update the attribute of the current attribute instance in the current table insert the attribute if it is not created before.

Parameters

sName	: name of the attribute field
sIn	value of the attribute field

Returns: true if succeed.

§ ValidateDatabase()

void AttributeProvider::ValidateDatabase ( )

ensure that the database has been set up properly.

If not, ResetDatabase() is called to reset the database to blank

The documentation for this class was generated from the following files:

Client/trunk/ParaEngineClient/3dengine/AttributeProvider.h
Client/trunk/ParaEngineClient/3dengine/AttributeProvider.cpp

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

§ AttributeProvider()

Member Function Documentation

§ CreateTableIfNotExists()

§ DeleteAttribute()

§ DoesAttributeExists()

§ GetAttribute() [1/2]

§ GetAttribute() [2/2]

§ GetTableName()

§ InsertAttribute() [1/2]

§ InsertAttribute() [2/2]

§ IsValid()

§ LoadAttributeObject()

§ ResetTable()

§ SaveAttributeObject()

§ SetDBEntity()

§ SetTableName()

§ UpdateAttribute()

§ ValidateDatabase()