InstallationQueue

BeginQueuedInstalls EndQueuedInstalls InstallInto MakeValid PerformPendingInstalls

Attributes

Class InstallationQueue defines no new attributes.

Fields

instance InstallationQueue tag;
   numInstalled: 0;
 queuedInstalls: false;
end instance;

Define Class InstallationQueue;
    inherits from DenseObjectList;

    field numInstalled : Unsigned;
    field queuedInstalls: Boolean;

    operation BeginQueuedInstalls();
        // begin queueing installs instead of performing them immediately.
        // calls to BeginQueuedInstalls cannot be nested.
    operation EndQueuedInstalls();
        // stop queueing installs, and perform all pending installs.
    operation PerformPendingInstalls();
        // calls InstallSelf() on all items in queue.

    overrides MakeValid;
        // makes sure that numInstalled remains consistent if objects in
        // our queue have become 
    overrides InstallInto;
        // adds installee to queue, and calls PerformPendingInstalls() if
        // we are not currently queueing installs.  flags and parameters
        // are ignored.
end class;