Object Technology Licensing Corporation

Arn J Schaeffer

David R Anderson

John R Matheny

Christopher White

An event notification system for propagating object-change information. The notification system supports change notification without queues in an object-based application or operating system and can be scaled to propagate large numbers of events among a large plurality of objects. The event notification system interconnects a plurality of event source and event receiver objects. Any object, such as a command object, may operate as either an event receiver object, an event source object or both. A notification object is created by a source object to transport, from a source to a receiver, descriptive information about a change, which includes a particular receiver object method and a pointer to the source object that sent the notification. A receiver object must register with a connection object its &ldquo;interest&rdquo; in receiving notification of changes; specifying both the event type and the particular source object of interest. After establishing such connections, the receiver object receives only the events of the specified type for the source objects &ldquo;of interest&rdquo; and no others. This delegation of event selection avoids central event queuing altogether and so limits receiver object event processing that the invention can be scaled to large systems operating large numbers of objects.

Object-oriented event notification system with listener registration of both interests and methods

A method and apparatus for a menu based system containing size and location information is disclosed. Each menu contains a list of menu items containing a command and variables that reflect the command's current appearance. This includes status information determinative of the menu item's state (enabled/disabled), its name, its associated graphic, and whether its appearance is currently valid. Each of these were initialized when the menu item was created. The invention creates a menu item from a command, where a menu item is another object data structure containing a command sequence. The menu item is added to a list of menu items, and initialized as an invalid appearance. Later when the menu item is selected from a pull down menu, the appearance state is recomputed based on the system state.

Growing community of inventors

Belmont, CA, United States of America

Arn J Schaeffer