nn::nex::ChangeMasterStationOperation Class

Syntax

class ChangeMasterStationOperation : public nn::nex::DOOperation

Description

DOOperation class that executes when a duplication master migrates.

Migration is the act of transferring control of a duplicated object to a different station. The operations executed in this class occur as a result of duplication master migration. As a result of these operations, duplicated objects maintained by the local station change roles. One of the following changes takes place.

・A duplica (DuplicatedObject::IsADuplica) becomes a duplication master (DuplicatedObject::IsADuplicationMaster) through a promotion in authority (IsAPromotion).
・A duplication master becomes a duplica through a demotion in authority (IsADemotion).
・A duplica remains unchanged (the IsARoleChange function returns false).

When migration of a duplicated object occurs, ChangeMasterStationOperation is called targeting every station that maintains that duplicated object (whether the station maintains the duplication master or a duplica).

When ChangeMasterStationOperation is called, the following sequence of events take place.

SafetyExecutive is executed to determine whether this migration is acceptable. If not, the process ends here.
・The DataSet::OperationBegin function is called on all datasets.
・The DuplicatedObject::OperationBegin function is called.
・The object migrates to a new station and the duplication master's StationID (the duplicated object ID of the station) is updated.
・The duplication master and duplica lists are updated in the Duplicated Object store.
・The DataSet::OperationEnd function is called on all datasets.
・The DuplicatedObject::OperationEnd function is called.

This operation is not called on DuplicatedObject when the system is locked (Scheduler::SystemLock).

Enumerated Types

Type Enumerated type representing the types of operations called by the system. (Inherits Operation.)

Member Functions

GetOldMasterStation Gets the duplicated object handle of the station that was the duplication master before execution of this operation.
GetNewMasterStation Gets the duplicated object handle of the station that becomes the duplication master after execution of this operation.
IsAPromotion Gets whether this operation results in authority promotion of a duplicated object.
IsADemotion Gets whether this operation results in authority demotion of a duplicated object.
IsARoleChange Gets whether this operation results in a change of authority of a duplicated object.
GetAssociatedDOHandle Gets the duplicated object handle associated with this operation. (Inherits DOOperation.)
GetOrigin Gets a duplicated object handle to a station that has called a function that generates an operation object as a result of the call. (Inherits DOOperation.)
GetAssociatedDO Gets a pointer to the duplicated object associated with an operation. (Inherits DOOperation.)
PV GetType Returns the type of this operation object.
GetUserData Gets user-defined values. (Inherits Operation.)
SetUserData Sets user-defined values. (Inherits Operation.)
PV GetClassNameString Gets the class name of this operation object.
S DynamicCast Uses runtime information for dynamic casting. (Inherits Operation.)
S SetTraceFilter Sets the callback function that specifies when to run traces on operation objects. (Inherits Operation.)

Class Hierarchy

nn::nex::RootObject
  nn::nex::Operation
    nn::nex::DOOperation
      nn::nex::ChangeMasterStationOperation

Revision History

2011/01/27
Initial version.

CONFIDENTIAL