Method and system for resetting references to deleted software structures

• US 6,078,931 A
• Filed: 01/14/1998
• Issued: 06/20/2000
• Est. Priority Date: 01/14/1998
• Status: Expired due to Term

• Current Assignee: Ricoh Company Limited, Ricoh Corporation (Ricoh Company Limited)
• Original Assignee: Ricoh Company Limited, Ricoh Corporation (Ricoh Company Limited)
• Inventors: Motoyama, Tetsuro
• Primary Examiner(s): Homere, Jean R.
• Application Number:
  US09/007,100
• Time in Patent Office: 888 Days
• Field of Search: 707/203, 707/103, 707/10, 395/712
• US Class Current: 1/1
• CPC Class Codes: G06F 9/4488 Object-oriented
• CPC Class Codes: Y10S 707/99954 Version management

Abstract

A method, system, computer program product, memory, and object-oriented system for resetting references to software structures after the software structures have been deleted. A software structure to be referenced or used by plural users in the same or different modules is created having an array or list of references to users, initialized to reflect no current users of the software structure. A user software structure is created having a reference pointer, or pointer variable, initialized to reflect no current referenced software structure. When the user software structure requests a reference to the referenced software structure, the reference pointer of the user software structure is assigned the value of the reference to the used software structure. The user software structure is registered with the used software structure by inserting a reference to the user software structure in the array, or list of users in the used software structure. When a user software structure relinquishes reference to the used software structure, the reference pointer of the user software structure is used to reference the used software structure. The array of users is accessed to delete the reference to the user software structure which is relinquishing reference to the used software structure, thereby unregistering the user software structure. The reference pointer of the user software structure is set to zero or null to reflect no current reference for the user software structure.

Claims

1. A computer implemented method for managing references to software structures, comprising the steps of:

creating a first software structure having a list of references to users of the first software structure;

creating a reference to the first software structure for a second software structure; and

adding a reference to the second software structure to the list of references to users of the first software structure.

2. A method according to claim 1, wherein:

the step of creating the first software structure comprises;

creating the first software structure to have the list of references to users include a list of addresses of the users of the first software structure;

the step of creating the reference to the first software structure comprises;

creating the reference to the first software structure to include an address of the first software structure for the second software structure; and

the step of adding the reference comprises;

adding the reference to the second software structure, the reference to the second software structure including an address of the second software structure, to the list of references to users of the first software structure.

3. A method according to claim 1, wherein:

the step of creating the first software structure comprises;

creating the first software structure to have the list of references to users include a list of names of the users of the first software structure;

the step of creating the reference to the first software structure comprises;

creating the reference to the first software structure to include a name of the first software structure for the second software structure; and

the step of adding the reference comprises;

adding the reference to the second software structure, the reference to the second software structure including a name of the second software structure, to the list of references to users of the first software structure.

4. A method according to claim 1, wherein:

the step of creating the first software structure comprises;

creating the first software structure to include a first software object which has the list of references to users of the first software structure; and

the step of creating the reference to the first software structure comprises;

creating the reference to the first software structure for a second software structure which includes a second software object.

5. A method according to claim 1, further comprising the steps of:

processing the list of references to users of the first software structure to obtain the reference to the second software structure; and

setting the reference to the first software structure of the second software structure to indicate deletion of the first software structure using the reference to the second software structure obtained by the processing step.

6. A method according to claim 5, further comprising the step of:

deleting the first software structure.

7. A method according to claim 1, further comprising the steps of:

obtaining the list of references to users of the first software structure;

deleting the reference to the second software structure from the list of references to users of the first software structure; and

deleting the second software structure.

8. A method according to claim 7, wherein:

the step of obtaining the list of references to users of the first software structure further comprises;

obtaining the reference to the first software structure of the second software structure; and

obtaining the list of references to users of the first software structure using the reference to the first software structure which has been obtained.

9. A method according to claim 1, further comprising the steps of:

obtaining the list of references to users of the first software structure;

deleting the reference to the second software structure from the list of references to users of the first software structure; and

modifying the reference to the first software structure of the second software structure to a modified reference value.

10. A method according to claim 9, wherein:

the step of obtaining the list of references to users of the first software structure further comprises;

obtaining the reference to the first software structure of the second software structure; and

obtaining the list of references to users of the first software structure using the reference to the first software structure which has been obtained.

11. A method according to claim 1, further comprising the steps of:

creating a reference to the first software structure for a third software structure; and

adding a reference to the third software structure to the list of references to users of the first software structure.

12. A method according to claim 11, further comprising the steps of:

processing the list of references to users of the first software structure to obtain the reference to the second software structure;

setting the reference to the first software structure of the second software structure to indicate deletion of the first software structure using the reference to the second software structure which has been obtained;

processing the list of references to users of the first software structure to obtain the reference to the third software structure; and

setting the reference to the first software structure of the third software structure to indicate deletion of the first software structure using the reference to the third software structure which has been obtained.

13. A system for managing references to software structures for implementation by a computer, comprising:

a storage means;

means for creating a first software structure having a list of references to users of the first software structure;

means for creating a reference to the first software structure for a second software structure; and

means for adding a reference to the second software structure to the list of references to users of the first software structure.

14. A system according to claim 13, wherein:

the means for creating the first software structure comprises;

means for creating the first software structure to have the list of references to users include a list of addresses of the users of the first software structure;

the means for creating the reference to the first software structure comprises;

means for creating the reference to the first software structure to include an address of the first software structure for the second software structure; and

the means for adding the reference comprises;

means for adding the reference to the second software structure, the reference to the second software structure including an address of the second software structure, to the list of references to users of the first software structure.

15. A system according to claim 13, wherein:

the means for creating the first software structure comprises;

means for creating the first software structure to have the list of references to users include a list of names of the users of the first software structure;

the means for creating the reference to the first software structure comprises;

means for creating the reference to the first software structure to include a name of the first software structure for the second software structure; and

the means for adding the reference comprises;

means for adding the reference to the second software structure, the reference to the second software structure including a name of the second software structure, to the list of references to users of the first software structure.

16. A system according to claim 13, wherein:

the means for creating a first software structure comprises;

means for creating the first software structure to include a first software object which has the list of references to users of the first software structure; and

the means for creating the reference to the first software structure comprises;

means for creating the reference to the first software structure for a second software structure which includes a second software object.

17. A system according to claim 13, further comprising:

means for processing the list of references to users of the first software structure to obtain the reference to the second software structure; and

means for setting the reference to the first software structure of the second software structure to indicate deletion of the first software structure using the reference to the second software structure obtained by the means for processing the list of references to users of the first software structure.

18. A system according to claim 17, further comprising:

means for deleting the first software structure.

19. A system according to claim 13, further comprising:

means for obtaining the list of references to users of the first software structure;

means for deleting the reference to the second software structure from the list of references to users of the first software structure; and

means for deleting the second software structure.

20. A system according to claim 19, wherein:

the means for obtaining the list of references to users of the first software structure further comprises;

means for obtaining the reference to the first software structure of the second software structure; and

means for obtaining the list of references to users of the first software structure using the reference to the first software structure which has been obtained.

21. A system according to claim 13, further comprising:

means for obtaining the list of references to users of the first software structure;

means for deleting the reference to the second software structure from the list of references to users of the first software structure; and

means for modifying the reference to the first software structure of the second software structure to a modified reference value.

22. A system according to claim 21, wherein:

the means for obtaining the list of references to users of the first software structure further comprises;

means for obtaining the reference to the first software structure of the second software structure; and

means for obtaining the list of references to users of the first software structure using the reference to the first software structure obtained by the means for obtaining the reference to the first software structure of the second software structure.

23. A system according to claim 13, further comprising:

means for creating a reference to the first software structure for a third software structure; and

means for adding a reference to the third software structure to the list of references to users of the first software structure.

24. A system according to claim 23, further comprising:

means for processing the list of references to users of the first software structure to obtain the reference to the second software structure;

means for setting the reference to the first software structure of the second software structure to indicate deletion of the first software structure using the reference to the second software structure which has been obtained by the means for processing the list of references to users of the first software structure to obtain the reference to the second software structure;

means for processing the list of references to users of the first software structure to obtain the reference to the third software structure; and

means for setting the reference to the first software structure of the third software structure to indicate deletion of the first software structure using the reference to the third software structure which has been obtained by the means for processing the list of references to users of the first software structure to obtain the reference to the third software structure.

25. A computer program product including a computer readable medium for managing references to software structures, comprising:

means for creating a first software structure having a list of references to users of the first software structure;

means for creating a reference to the first software structure for a second software structure; and

means for adding a reference to the second software structure to the list of references to users of the first software structure.

26. A computer program product according to claim 25, wherein:

the means for creating the first software structure comprises;

means for creating the first software structure to have the list of references to users include a list of addresses of the users of the first software structure;

the means for creating the reference to the first software structure comprises;

means for creating the reference to the first software structure to include an address of the first software structure for the second software structure; and

the means for adding the reference comprises;

means for adding the reference to the second software structure, the reference to the second software structure including an address of the second software structure, to the list of references to users of the first software structure.

27. A computer program product according to claim 25, wherein:

the means for creating the first software structure comprises;

means for creating the first software structure to have the list of references to users include a list of names of the users of the first software structure;

the means for creating the reference to the first software structure comprises;

means for creating the reference to the first software structure to include a name of the first software structure for the second software structure; and

the means for adding the reference comprises;

means for adding the reference to the second software structure, the reference to the second software structure including a name of the second software structure, to the list of references to users of the first software structure.

28. A computer program product according to claim 25, wherein:

the means for creating a first software structure comprises;

means for creating the first software structure to include a first software object which has the list of references to users of the first software structure; and

the means for creating the reference to the first software structure comprises;

means for creating the reference to the first software structure for a second software structure which includes a second software object.

29. A computer program product according to claim 25, further comprising:

means for processing the list of references to users of the first software structure to obtain the reference to the second software structure; and

means for setting the reference to the first software structure of the second software structure to indicate deletion of the first software structure using the reference to the second software structure obtained by the means for processing the list of references to users of the first software structure.

30. A computer program product according to claim 29, further comprising:

means for deleting the first software structure.

31. A computer program product according to claim 25, further comprising:

means for obtaining the list of references to users of the first software structure;

means for deleting the reference to the second software structure from the list of references to users of the first software structure; and

means for deleting the second software structure.

32. A computer program product according to claim 31, wherein:

the means for obtaining the list of references to users of the first software structure further comprises;

means for obtaining the reference to the first software structure of the second software structure; and

means for obtaining the list of references to users of the first software structure using the reference to the first software structure which has been obtained.

33. A computer program product according to claim 25, further comprising:

means for obtaining the list of references to users of the first software structure;

means for deleting the reference to the second software structure from the list of references to users of the first software structure; and

means for modifying the reference to the first software structure of the second software structure to a modified reference value.

34. A computer program product according to claim 33, wherein:

the means for obtaining the list of references to users of the first software structure further comprises;

means for obtaining the reference to the first software structure of the second software structure; and

means for obtaining the list of references to users of the first software structure using the reference to the first software structure obtained by the means for obtaining the reference to the first software structure of the second software structure.

35. A computer program product according to claim 25, further comprising:

means for creating a reference to the first software structure for a third software structure; and

means for adding a reference to the third software structure to the list of references to users of the first software structure.

36. A computer program product according to claim 35, further comprising:

means for processing the list of references to users of the first software structure to obtain the reference to the second software structure;

means for setting the reference to the first software structure of the second software structure to indicate deletion of the first software structure using the reference to the second software structure which has been obtained by the means for processing the list of references to users of the first software structure to obtain the reference to the second software structure;

means for processing the list of references to users of the first software structure to obtain the reference to the third software structure; and

means for setting the reference to the first software structure of the third software structure to indicate deletion of the first software structure using the reference to the third software structure which has been obtained by the means for processing the list of references to users of the first software structure to obtain the reference to the third software structure.

37. A memory embodied in a computer for managing references to software structures comprising:

a first software structure stored in the memory comprising;

a list of references to users of the first software structure; and

a second software structure stored in the memory comprising;

a reference to the first software structure,

wherein the list of references to users of the first software structure includes a reference to the second software structure.

38. A memory according to claim 37, wherein:

the first software structure stored in the memory further comprises;

a list of references to users of the first software structure which includes a list of addresses of the users of the first software structure; and

the second software structure stored in the memory further comprises;

a reference to the first software structure which includes an address of the first software structure,

wherein the list of references to users of the first software structure includes a reference to the second software structure which includes an address of the second software structure.

39. A memory according to claim 37, wherein:

the first software structure stored in the memory further comprises;

a list of references to users of the first software structure which includes a list of names of the users of the first software structure; and

the second software structure stored in the memory further comprises;

a reference to the first software structure which includes a name of the first software structure,

wherein the list of references to users of the first software structure includes a reference to the second software structure which includes a name of the second software structure.

40. A memory according to claim 37, wherein:

the first software structure stored in the memory further comprises;

a first software object which has the list of references to users of the first software structure; and

the second software structure stored in the memory further comprises;

a second software object which has the reference to the first software structure.

41. A memory according to claim 37, further comprising:

a third software structure stored in the memory comprising;

a reference to the first software structure,

wherein the list of references to users of the first software structure includes a reference to the third software structure.

42. An object-oriented system for managing references to software structures for implementation by a computer in an object-oriented framework, comprising:

a memory;

means for creating a first software structure in the memory having a list of references to users of the first software structure;

means for creating a reference to the first software structure for a second software structure in the memory; and

means for adding a reference to the second software structure to the list of references to users of the first software structure in the memory,

wherein at least one of the means for creating a first software structure, the means for creating a reference, the means for adding a reference, the first software structure, and the second software structure includes a software object.

43. A system according to claim 42, wherein the second software structure includes a software object derived from a base class having a reference pointer to the first software structure and the means for creating the reference to the first software structure further comprises:

means for creating a reference to the first software structure for the second software structure which includes a software object derived from a base class having a reference pointer to the first software structure.

44. A system according to claim 43, further comprising:

means for creating a reference to the first software structure for a third software structure; and

means for adding a reference to the third software structure to the list of references to users of the first software structure.

45. A system according to claim 44, further comprising:

means for processing the list of references to users of the first software structure to obtain the reference to the second software structure;

means for setting the reference to the first software structure of the second software structure to indicate deletion of the first software structure using the reference to the second software structure which has been obtained by the means for processing the list of references to users of the first software structure to obtain the reference to the second software structure;

means for processing the list of references to users of the first software structure to obtain the reference to the third software structure; and

means for setting the reference to the first software structure of the third software structure to indicate deletion of the first software structure using the reference to the second software structure which has been obtained by the means for processing the list of references to users of the first software structure to obtain the reference to the third software structure.

46. A system according to claim 43, further comprising:

means for processing the list of references to users of the first software structure to obtain the reference to the second software structure; and

means for setting the reference to the first software structure of the second software structure to indicate deletion of the first software structure using the reference to the second software structure obtained by the means for processing the list of references to users of the first software structure.

47. A system according to claim 46, further comprising:

means for deleting the first software structure.

48. A system according to claim 47, further comprising:

means for obtaining the list of references to users of the first software structure;

means for deleting the reference to the second software structure from the list of references to users of the first software structure; and

means for deleting the second software structure.

49. A system according to claim 48, further comprising:

means for modifying the reference to the first software structure of the second software structure to a modified reference value.

50. A system according to claim 49, wherein:

at least one of

the means for creating a first software structure,

the means for creating a reference to the first software structure for a second software structure,

the means for adding a reference to the second software structure to the list of references to users of the first software structure,

the means for processing the list of references to users of the first software structure to obtain the reference to the second software structure,

the means for setting the reference to the first software structure of the second software structure to indicate deletion of the first software structure,

the means for deleting the first software structure,

the means for obtaining the list of references to users of the first software structure,

the means for deleting the reference to the second software structure from the list of references to users of the first software structure,

the means for deleting the second software structure, and

the means for modifying the reference to the first software structure of the second software structure includes a software method.