CommsDat::CMDBSession Class Reference

#include <metadatabase.h>

Link against: commsdat.lib

class CommsDat::CMDBSession : public CBase, public CBase

Inherits from

CommsDat::CMDBSession
- CBase
- CBase

Public Member Functions
	~CMDBSession()
IMPORT_C TInt	CancelAllNotifications()
IMPORT_C void	ClearAttributeMask(TMDBAttributeFlags)
IMPORT_C void	Close()
IMPORT_C void	CommitTransactionL()
IMPORT_C TInt	IsInTransaction()
IMPORT_C TBool	IsSetAttributeMask(TMDBAttributeFlags)
IMPORT_C TVersion	LatestVersion()
IMPORT_C CMDBSession *	NewL(TVersion)
IMPORT_C CMDBSession *	NewLC(TVersion)
IMPORT_C void	OpenTransactionL()
IMPORT_C TInt	PublishProperties()
IMPORT_C void	RollbackTransactionL()
IMPORT_C void	SetAttributeMask(TMDBAttributeFlags)
IMPORT_C TVersion	VersionInUse()

Inherited Functions
	CBase::CBase()
	CBase::Delete(CBase *)
	CBase::Extension_(TUint,TAny &,TAny )
	CBase::operator new(TUint)
	CBase::operator new(TUint,TAny *)
	CBase::operator new(TUint,TLeave)
	CBase::operator new(TUint,TLeave,TUint)
	CBase::operator new(TUint,TUint)
	CBase::~CBase()

Detailed Description

A session with the underlying storage server

Constructor & Destructor Documentation

~CMDBSession ( )

IMPORT_C

~CMDBSession

(

)

Virtual Destructor

Member Function Documentation

CancelAllNotifications ( )

IMPORT_C TInt

CancelAllNotifications

(

)

Cancel all notification requests that are outstanding from calls to MMetaDatabase::RequestNotification Individual requests can be cancelled via MMetaDatabase::CancelNotify.

Pre-condition: None

Return Value: KErrNone on success or a system-wide error code

ClearAttributeMask ( TMDBAttributeFlags )

IMPORT_C void

ClearAttributeMask

(

TMDBAttributeFlags

aAttributeFlags

)

Clear attribute mask settings, indicating required access level to stored data Clear flags in the attribute mask for this session

Flags indicate the requested access level to stored data

Attribute flags that have been set in this function will be cleared from the session's attribute mask and will be obeyed as restrictions in all database interactions, providing the client has enough platform security capabilities to back up the request

Pre-condition: None

Close ( )

IMPORT_C void

(

)

Close session with storage server. Deprecatedv9.1 Destructor is all that is required

CommitTransactionL ( )

IMPORT_C void

CommitTransactionL

(

)

Commit Transaction in database.

Pre-condition: None

Post-condition: On success the database is updated with data added, modified or deleted during the transaction
On failure, any open data containers may not be in sync with the database and should be discarded or reloaded

Leave Codes
Will	leave with KErrNotFound if not in transaction
Will	leave with a system-wide error code if an error occurs during commit

IsInTransaction ( )

IMPORT_C TInt

IsInTransaction

(

)

Query if this session is in a transaction with the database Return code will indicate Not in transaction, Already in transaction for this session, Write-lock not available. Another session has it.

Pre-condition: None

IsSetAttributeMask ( TMDBAttributeFlags )

IMPORT_C TBool

IsSetAttributeMask

(

TMDBAttributeFlags

aAttributeFlags

)

Check flags in attribute mask aAttributeFlags indicates the requested access level to stored data Attribute flags that have been set will be ignored as restrictions in all database interactions, providing the client has enough platform security capabilities to back up the request

Pre-condition: None

Return Value: ETrue if the flag is set in the session mask This means that the attribute is ignored in database interactions for this sessionEFalse if the flag is not set in the session mask This means that the attribute is obeyed in all database interactions for this session

LatestVersion ( )

IMPORT_C TVersion

LatestVersion

(

)

[static]

Returns the KCDCurrentVersion constant which maps to the KCDVersion1_1 constant for backward compatibility reason. Please avoid using this method when creating a CommsDat session object and use explicit schema version instead.

Deprecated

Pre-condition: None

Post-condition: None

NewL ( TVersion )

IMPORT_C CMDBSession *

NewL

(

TVersion

aRequiredVersion

)

[static]

Open a session with the storage server and establish data format version in use CommsDat always attempts to support the required version of the client-facing data set. The client must carefully choose the dataset version as it affects binary compatibility

aRequiredVersion If the requested version is deprecated but still supported, mapping will be performed within CommsDat to maintain Data and Binary compatibility for the client If the requested version is the latest version, no mapping will be performed and deprecated fields will be ignored A client that needs to maintain BC must use a specific version A client that always wants to use the latest dataset can start the session with KCDLatestVersion

Pre-condition: None

Post-condition: on success a session has been created and initialised

Leave Codes
KErrUnsupported	If an old unsupported version is requested
System-wide	error codes if there is an unexpected error

NewLC ( TVersion )

IMPORT_C CMDBSession *

NewLC

(

TVersion

aRequiredVersion

)

[static]

As NewL and adds Session to the CleanupStack

OpenTransactionL ( )

IMPORT_C void

OpenTransactionL

(

)

Open Transaction with storage server and obtain write lock - if not already set

Pre-condition: None

Post-condition: on success the session has exclusive write access to the database

Leave Codes
Will	leave with KErrNotAvailable if Database write locked by another process
Will	report KErrAlreadyInTransaction if transaction this session is already in a transaction
Will	leave with a system-wide error code if an error occurs during commit

Capability
WriteDeviceData

PublishProperties ( )

IMPORT_C TInt

PublishProperties

(

)

Attempt to create publish/subscribe properties if not already defined.

This function is normally called as a setup activity by System components

Pre-condition: None

Return Value: KErrNone on success. Otherwise a system-wide error code

Capability
WriteDeviceData	- since these properties are created in KUidSystemCategory category.

RollbackTransactionL ( )

IMPORT_C void

RollbackTransactionL

(

)

Cancel Transaction with database and rollback all associated changes

Pre-condition: None - though for correct usage, ensure a transaction is already open

Post-condition: Any open data containers may not be in sync with the database and should be discarded or reloaded

Leave Codes
Will	fail with KErrNotFound if not in transaction

SetAttributeMask ( TMDBAttributeFlags )

IMPORT_C void

SetAttributeMask

(

TMDBAttributeFlags

aAttributeFlags

)

Set attributes to ignore for all database operations during this session

aAttributeFlags indicates the requested access level to stored data. Attributes set by this call will be ignored as restrictions in all database interactions, providing the client has enough platform security capabilities to back up the request

Pre-condition: None

VersionInUse ( )

IMPORT_C TVersion

VersionInUse

(

)

Lookup data format version currently in use by client