IRunningObjectTable
The IRunningObjectTable
interface manages access to the Running Object Table (ROT), a globally
accessible look-up table on each workstation. A workstation s ROT keeps track of those objects that can be
identified by a moniker and that are currently running on the workstation. When
a client tries to bind a moniker to an object, the moniker checks the ROT to
see if the object is already running; this allows the moniker to bind to the
current instance instead of loading a new one.
The ROT
contains entries of the form:
(pmkObjectName, pUnkObject)
The pmkObjectName
element is a pointer to the moniker that identifies the running object. The pUnkObject
element is a pointer to the running object itself. During the binding process,
monikers consult the pmkObjectName entries in the Running Object Table
to see if an object is already running.
Objects that
can be named by monikers must be registered with the ROT when they are loaded
and their registration must be revoked when they are no longer running.
When to Implement
You do not
need to implement this interface. The system provides an implementation of the
Running Object Table that is suitable for all situations.
When to Use
You typically
use the ROT if you re a moniker provider (that is, you hand out monikers
identifying your objects to make them accessible to others) or if you re writing your own moniker class (that is,
implementing the IMoniker
If you are a
moniker provider, you register your objects with the ROT when they begin
running and revoke their registrations when they are no longer running. This
enables the monikers that you hand out to be bound to running objects. You
should also use the ROT to record the object s
last modification time. You can get an IRunningObjectTable interface
pointer to the local ROT by calling the GetRunningObjectTable
The most
common type of moniker provider is a compound-document link source. This
includes server applications that support linking to their documents (or
portions of a document) and container applications that support linking to
embeddings within their documents. Server applications that do not support
linking can also use the ROT to cooperate with container applications that
support linking to embeddings.
If you are
writing your own moniker class, you use the ROT to determine whether a object
is running and to retrieve the object s
last modification time. You can get an IRunningObjectTable interface
pointer to the local ROT by calling the IBindCtx::GetRunningObjectTable
Methods in VTable Order
IUnknown Methods |
Description |
QueryInterface |
Returns
pointers to supported interfaces. |
AddRef |
Increments
reference count. |
Release |
Decrements
reference count. |
IRunningObjectTable
Methods |
Description |
Register |
Registers
an object with the ROT. |
Revoke |
Revokes an
object s registration with the ROT. |
IsRunning |
Checks
whether an object is running. |
GetObject |
Returns a
pointer to an object given its moniker. |
NoteChangeTime |
Notifies
the ROT that an object has changed. |
GetTimeOfLastChange |
Returns the
time an object was last changed. |
EnumRunning |
Returns an
enumerator for the ROT. |
See Also
IBindCtx::GetRunningObjectTable, IROTData