Abstract: Methods, systems, and schema are provided for enforcing security on an attribute of an object. An instance of an object is created or modified using the schema where a number of the attributes for the object include descriptors. The attributes of the created or modified object are checked to ensure that the modifier has access rights to the attributes. If the modifier does not have the access rights, then values are not assigned to the attributes requested by the modifier. When the modifier provides values for an attribute having the corresponding descriptor, the values are also checked to determine if they are references to a second object. In which case, a check is made to ensure the modifier has an access right to the second object. If no such access right exists, then the values are not assigned to the attribute as originally requested by the modifier.

Abstract: An event notification facility includes an interface by which programs register for notification of an event. When registering, each program identifies a type of event and a mechanism by which the program is to be notified if and when an event of the identified type occurs. At the program's option, it can request that it be notified "last," i.e. after all other programs have been notified of the event. The event notification facility also includes a means for storing the registration requests and for associating each registration request with a type of event. Once a program is registered to be notified of an event last, the event notification facility rejects all other requests from programs to be notified of the same event last, however preferably other programs can still register for notification of the event. Finally, the event notification facility includes a means for notifying each registered program when the event occurs.