Method for providing stand-in objects

• US 8,667,508 B2
• Filed: 05/02/2012
• Issued: 03/04/2014
• Est. Priority Date: 12/07/1994
• Status: Expired due to Term

• Current Assignee: Next Software Incorporated (Apple Inc.)
• Original Assignee: Next Software Incorporated (Apple Inc.)
• Inventors: Williamson, Richard, Upson, Linus, Willhite, Daniel, Greenfield, Jack
• Primary Examiner(s): Sough, H S
• Assistant Examiner(s): Wood, William C
• Application Number:
  US13/462,551
• Publication Number:
  US 20120246664A1
• Time in Patent Office: 671 Days
• Field of Search: None
• US Class Current: 719/316
• CPC Class Codes: G06F 8/24 Object-oriented
• CPC Class Codes: G06F 9/4488 Object-oriented
• CPC Class Codes: G06F 9/449 Object-oriented method invocation or resolution
• CPC Class Codes: Y10S 707/99944 Object-oriented database structure
• CPC Class Codes: Y10S 707/99945 Object-oriented database structure processing

Abstract

A method for providing stand-in objects, where relationships among objects are automatically resolved in an object oriented relational database model without the necessity of retrieving data from the database until it is needed. A “fault” class is defined, as well as fault objects whose data haven'"'"'t yet been fetched from the database. An object that'"'"'s created for the destination of a relationship whenever an object that includes the relationship is fetched from the database. When an object is fetched that has relationships, fault objects are created to “stand-in” for the destination objects of those relationships. Fault objects transform themselves into the actual enterprise objects—and fetch their data—the first time they'"'"'re accessed. Subsequently, messages sent to the target objects are responded to by the objects themselves.

Claims

1. A method for managing object relationships comprising:

using a processor to instantiate a first object having a relationship with a second object; and

using the processor to create a fault object to stand in place of said second object with respect to said relationship;

wherein the fault object comprises at least one attribute of the second object, such that the fault object responds to a message requesting the value of the at least one attribute without the fault object transforming into the second object, wherein the fault object includes an instance variable in which a pointer to a data value of the second object is stored and the fault object is configured to transform itself into the second object in the event a message that requires retrieval of the data value of the second object is received.

2. A method as recited in claim 1, further comprising associating said first object with said fault object.

3. A method as recited in claim 1, further comprising associating said fault object with said relationship of the first object with the second object.

4. A method as recited in claim 1, wherein the message invokes a method of the second object which the fault object is not configured to perform.

5. A method as recited in claim 1, wherein the message invokes a method that requires a data that the fault object is not configured to retrieve or store.

6. A method as recited in claim 1, wherein the fault object is configured to appear to the first object in at least one respect to be the same as the second object at least in part by being configured to respond to a second message received from the first object in a same manner in which the second object would respond to the second message.

7. A method as recited in claim 1, wherein the fault object is further configured to:

determine based at least in part on the message that the second object is needed; and

transform itself into the second object, in response to the determination that the second object is needed.

8. A method as recited in claim 7, wherein the fault object is configured to transform itself into the second object at least in part by retrieving from a data source a data associated with the second object.

9. A method as recited in claim 8, wherein the data is stored in a data source that comprises one or more of the following:

a database;

an object-oriented database;

a user interface; and

a file system.

10. A method as recited in claim 7, wherein the fault object is configured to transform itself into the second object at least in part by rewriting an attribute of the fault object to a value associated with the second object.

11. A method as recited in claim 10, wherein the value comprises a pointer or other identifier associated with a class description.

12. A method as recited in claim 1, wherein an actual class of which the second object is an instance is stored as an instance variable of the fault object.

21. The method of claim 1, wherein the fault object transforms itself into the second object by replacing the fault object with the second object.

13. A non-transitory computer readable storage medium comprising computer instructions, which when executed by a computer cause the computer to perform the steps of:

instantiating a first object having a relationship with a second object; and

creating a fault object to stand in place of said second object with respect to said relationship;

wherein the fault object comprises at least one attribute of the second object, such that the fault object responds to a message requesting the value of the at least one attribute without the fault object transforming into the second object, wherein the fault object includes an instance variable in which a pointer to a data value of the second object is stored and the fault object is configured to transform itself into or replace itself with the second object in the event a message that requires retrieval of the data value of the second object is received.

14. A non-transitory computer readable storage medium as recited in claim 13, wherein the fault object is configured to transform itself into or replace itself with the second object in the event an indication is received that a method associated with the data has been invoked.

15. A non-transitory computer readable storage medium as recited in claim 13, wherein the fault object is configured to appear to the first object in at least one respect to be the same as the second object at least in part by being configured to respond to a message received from the first object in a same manner in which the second object would respond to the message.

16. A non-transitory computer readable storage medium as recited in claim 13, wherein an actual class of which the second object is an instance is stored as an instance variable of the fault object.

22. The computer readable storage medium of claim 13, wherein the fault object transforms itself into the second object by replacing the fault object with the second object.

17. A computer system, comprising:

a memory configured to store a first object having a relationship with a second object; and

a processor coupled to the memory and configured to create in said memory a fault object to stand in place of said second object with respect to said relationship;

wherein the fault object comprises at least one attribute of the second object, such that the fault object responds to a message requesting the value of the at least one attribute without the fault object transforming into the second object, wherein the fault object includes an instance variable in which a pointer to a data value of the second object is stored and the fault object is configured to transform itself into the second object in the event a message that requires retrieval of the data value of the second object is received.

18. A computer system as recited in claim 17, wherein the message is received from the first object.

19. A computer system as recited in claim 17, wherein the message invokes a method of the second object which the fault object is not configured to perform.

20. A computer system as recited in claim 17, wherein responding to the message requires a data associated with the second object which is not available to the fault object.

23. The computer system of claim 17, wherein the fault object transforms itself into the second object by replacing the fault object with the second object.