Object oriented notification system

Abstract

A notification of a change in a notification source object is provided to a notification receiver object by creating a connection to the notification receiver object, adding to the connection at least one interest that describes a notification from the notification source object and registering the connection with the notification source object to indicate an interest in the notification. When a change occurs in the notification source object, a notification that describes the change is generated and, for each connection having an interest in the notification, that notification is dispatched to the notification receiver object connected to that connection.

1 . A computer-implemented method for use in a computer system having a memory and a processor, the method providing a notification of a change in a notification source object to a notification receiver object wherein the processor performs the steps of:
 (a) creating in the memory a connection to the notification receiver object;   (b) adding to the connection at least one interest that describes a notification from the notification source object;   (c) registering the connection with the notification source object to indicate an interest in the notification;   (d) when a change occurs in the notification source object, generating a notification that describes the change; and   (e) for each connection having an interest in the notification generated in step (d), dispatching that notification to the notification receiver object connected to that connection.   
     
     
         2 . The method of  claim 1  wherein the notification contains descriptive information about the change. 
     
     
         3 . The method of  claim 1  wherein each interest is defined by the notification source object. 
     
     
         4 . The method of  claim 1  wherein step (e) comprises dispatching that notification to a method in the notification receiver object so that the notification receiver can respond to the change. 
     
     
         5 . The method of  claim 1  further comprising:
 (f) receiving that notification in the notification receiver object. 
 
     
     
         6 . Apparatus for use in a computer system having a memory and a processor, the apparatus providing a notification of a change in a notification source object to a notification receiver object, the apparatus comprising:
 means creating in the memory a connection to the notification receiver object;   means for adding to the connection at least one interest that describes a notification from the notification source object;   means for registering the connection with the notification source object to indicate an interest in the notification;   means operable when a change occurs in the notification source object, for generating a notification that describes the change; and   means operable for each connection having an interest in the notification generated by the means for generating a notification, for dispatching that notification to the notification receiver object connected to that connection.   
     
     
         7 . The apparatus of  claim 6  wherein the notification contains descriptive information about the change. 
     
     
         8 . The apparatus of  claim 6  wherein each interest is defined by the notification source object. 
     
     
         9 . The apparatus of  claim 6  wherein the means for dispatching that notification comprises means for dispatching that notification to a method in the notification receiver object so that the notification receiver can respond to the change. 
     
     
         10 . The apparatus of  claim 6  further comprising means for receiving that notification in the notification receiver object.