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ODStorageUnitView
- Superclasses
ODObject- Subclasses
- none
An object of the
ODStorageUnitViewclass provides thread-safe access to a storage unit by automatically focusing and locking the storage unit.Description
A storage-unit view represents a particular storage unit, prefocused on a particular focus context. Your part creates a storage-unit view object by focusing a storage unit then calling theCreateViewmethod (page 679) of that storage unit. You can pass the storage-unit view among your software components to give them access to the particular focused data stream.A storage-unit view has most of the functionality of a storage unit, except that it has no methods for changing the focus. When you access a storage unit through a storage-unit view, however, the storage-unit view automatically locks the storage unit during the access and unlocks it afterward.
The storage-unit view has an associated storage-unit cursor that represents the focus context of the storage-unit view. You can call the
GetCursormethod (page 735) of a storage-unit view to obtain its storage-unit cursor. If you make changes to that storage-unit cursor, you change the focus context of the storage-unit view. Typically, however, parts do not change the focus context of a storage-unit view.For more information related to storage units and storage-unit cursors, see the description of the classes
ODStorageUnit(page 664) andODStorageUnitCursor(page 716).Methods
This section presents summary descriptions of theODStorageUnitViewmethods grouped according to purpose, followed by detailed descriptions in alphabetical order.Storage
CloneInto- Copies to the specified destination storage unit all properties and values of the storage unit that created this storage-unit view.
Externalize- Resolves all promises in the storage unit that created this storage-unit view and saves all its properties and values to persistent, external storage.
Internalize- Reads into memory all properties and values from the storage unit that created this storage-unit view.
Storage Unit Manipulation
GetStorageUnit- Returns a reference to the storage unit that created this storage-unit view.
AddProperty- Adds a property with the specified name to the storage unit that created this storage-unit view.
AddValue- Adds a value of the specified type to the focused property.
Remove- Removes all properties and values in the focus context from the storage unit that created this storage-unit view.
GetID- Returns the storage-unit ID for the storage unit that created this storage-unit view.
GetName- Returns the name of the storage unit that created this storage-unit view.
SetName- Sets the name of the storage unit that created this storage-unit view.
GetSize- Returns the size (number of bytes) of the data in the focus context.
Focus Context Access
GetCursor- Returns a reference to the storage-unit cursor representing the focus context of this storage-unit view.
GetProperty- Returns the name of the property in the focus context.
Value Manipulation
GetValue- Reads data from the focused value, starting at the offset (inclusive).
SetValue- Writes data to the focused value, starting at the offset (inclusive).
DeleteValue- Deletes data from the focused value, starting at the offset (inclusive).
InsertValue- Inserts data into the focused value, starting at the offset (inclusive).
GetOffset- Returns the offset of the focused value.
SetOffset- Sets the offset of the focused value.
GetType- Returns the type of the focused value.
SetType- Sets the type of the focused value.
GetGenerationNumber- Returns the generation number of the focused value.
IncrementGenerationNumber- Increments and returns the generation number of the focused value.
Persistent Reference Manipulation
GetIDFromStorageUnitRef- Returns the storage-unit ID of a referenced storage unit.
GetStrongStorageUnitRef- Creates a strong persistent reference to the specified storage unit.
GetWeakStorageUnitRef- Creates a weak persistent reference to the specified storage unit.
IsStrongStorageUnitRef- Returns a Boolean value that indicates whether the specified persistent reference is a strong persistent reference.
IsWeakStorageUnitRef- Returns a Boolean value that indicates whether the specified persistent reference is a weak persistent reference.
IsValidStorageUnitRef- Returns a Boolean value that indicates whether the specified persistent reference is valid.
RemoveStorageUnitRef- Makes a persistent reference invalid in the focused value.
Promise Manipulation
IsPromiseValue- Returns a Boolean value that indicates whether the focused value is a promise value.
GetPromiseValue- Reads promise data from the specified value of the focused property.
SetPromiseValue- Writes data to the specified value of the focused property, creating the value if it doesn't exist and making the value a promise value.
Creating Objects
CreateStorageUnitRefIterator- Creates a storage-unit reference iterator for the focused value.
Methods
AddProperty
AddValue
CloneInto
CreateStorageUnitRefIterator
DeleteValue
Externalize
GetCursor
GetGenerationNumber
GetID
GetIDFromStorageUnitRef
GetName
GetOffset
GetPromiseValue
GetProperty
GetSize
GetStorageUnit
GetStrongStorageUnitRef
GetType
GetValue
GetWeakStorageUnitRef
IncrementGenerationNumber
InsertValue
Internalize
IsPromiseValue
IsStrongStorageUnitRef
IsValidStorageUnitRef
IsWeakStorageUnitRef
Remove
RemoveStorageUnitRef
SetName
SetOffset
SetPromiseValue
SetType
SetValue
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