System and method for central refresh of place objects

• US 7,552,144 B2
• Filed: 12/31/2002
• Issued: 06/23/2009
• Est. Priority Date: 12/31/2002
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Shalabi, Sami M., Hill, Charles R., Dai, Hong
• Primary Examiner(s): Vo; Tim T
• Assistant Examiner(s): Dwivedi; Mahesh H
• Application Number:
  US10/334,296
• Publication Number:
  US 20040128271A1
• Time in Patent Office: 2,366 Days
• Field of Search: 709/205, 709/217, 709/219, 707/200, 707/201, 707/203
• US Class Current: 1/1
• CPC Class Codes: G06F 16/20 of structured data, e.g. relational data
• CPC Class Codes: Y10S 707/99952 Coherency, e.g. same view to multiple users
• CPC Class Codes: Y10S 707/99953 Recoverability

Abstract

A system for central refresh of a place includes a source place; a place type; a child place; each place comprising a plurality of place objects implemented as documents, logic, and associated design note, each design note including a plurality of items; some of the items being content items descriptive of content of the objects. A central refresh execution module determines whether an inherited place object is modified in a place by assigning to each item a sequence indicia indicative of change activity with respect to the item; generating and storing a stored checksum of sequence indicia generated for the content items; and responsive to a refresh operation with respect to the child place, and calculating a refresh checksum of sequence indicia for the content items. The central refresh execution module is responsive to the stored checksum and the refresh checksum being unequal for refreshing the child place.

Claims

1. A method for central refresh of a place, comprising:

providing a place type as a template derived from design elements and content elements of a source place;

deriving from said place type a least one child place;

each said child place including a plurality of objects implemented as documents, logic and design notes, said design notes including a plurality of items including a first selected subset of said items which are content items descriptive of content of said objects and a second subset which are descriptive of non-content items;

determining whether an inherited place object is modified in a place by

assigning to each of said plurality of items in said first selected subset and said second subset a sequence indicia indicative of change activity with respect to said item;

generating and storing a stored checksum of sequence indicia generated for only said first selected subset of content items; and

responsive to a refresh operation with respect to said child place, calculating a refresh checksum of sequence indicia for only said content items; and

responsive to said stored checksum and said refresh checksum being unequal, refreshing said child place.

2. The method of claim 1, further comprising:

associating algorithm version indicia with each of said refresh checksum and said stored checksum;

responsive to said algorithm version indicia being unequal for said refresh checksum and said stored checksum, adapting comparison of said refresh checksum and said stored checksum to differences in associated algorithms.

3. The method of claim 1, further comprising incrementing item sequence numbers and recalculating and updating said stored checksum each time said design note is refreshed.

4. The method of claim 3, further comprising executing a hierarchical inheritance process by:

selectively pulling updates from said source place to said place type and pulling updates from said place type to said child place; and

pushing updates from said place type selectively to all or specified said child places residing on a same server with said place type.

5. The method of claim 3, said refreshing further comprising iterating through all objects contained in said child place and refreshing all the objects inherited from said place type while not refreshing objects created and modified in said child place by a user.

6. The method of claim 5, said refreshing further comprising not refreshing objects which are members and groups.

7. The method of claim 5, further comprising:

determining whether a place object is inherited from its place type or created in said child place by a place user;

determining whether an inherited place object is modified in a place;

determining whether a place object which exists in said source place, but not in said child place, is new to said child place or is deleted in said child place by said place user;

executing a central refresh process as selectively choosing either a basic refresh or a replace process with respect to place objects;

wherein choosing a basic refresh process comprises updating and deleting only place objects not previously changed in said place which have been changed or deleted in its corresponding place type, and leaving unchanged all other place objects; and

wherein choosing a replace process comprises leaving objects unchanged for objects not changed in place or in place type and objects deleted from both place and place type, updating objects changed in place whether or not changed in place type, updating objects changed in place type and not changed in place, for objects deleted in place copying back objects from place type whether or not changed, deleting objects from place which have been deleted from place type.

8. The method of claim 7, said determining whether a place object is inherited from its place type or created in said child place by a place user comprising:

appending replaced indicia to object notes used to label inherited objects; and

during refresh, identifying objects not having said replaced indicia as local objects which have been created in said child place by said place user.

9. The method of claim 8, said replaced indicia being a time stamp that records last refresh/replace time of each said note;

and determining with reference to said last refresh/replace time whether a source object has changed since a last refresh.

10. The method of claim 9, said determining whether a place object which exists in said source place, but not in said child place, is new to said child place or is deleted in said child place by said place user comprising:

comparing a creation date of place object with a refresh date of said place stored in a place type stamp;

responsive to said creation date not being earlier than said refresh date, adding said new object to said child place; and

responsive to said creation date being earlier than said refresh date, for basic refresh not adding said new object to said child place.

11. The method of claim 1, further comprising distributing quick place changes in a clustered environment by:

on a first server, pulling updates from a source place to its corresponding place type;

on said first server, centrally pushing place type updates from said place type to its dependent child places on said first server; and

replicating said place type, said source place, and said child places on said first server to a second server in a cluster including said first server.

12. The method of claim 11, further comprising pulling updates to child places on said second server from a place type replica on said second server of a place type on said first server.

13. A system for central refresh of a place, comprising:

a source place;

a place type derived from design elements and content elements of said source place;

a child place;

each said place comprising a plurality of place objects, each said place object implemented as a document, logic and associated design note, each said design note including a plurality of items;

a first subset of said items being content items descriptive of content of said objects and a second subset of said items being non-content items;

a central refresh execution module for determining whether an inherited place object is modified in a place by

assigning to each of said plurality of items a sequence indicia indicative of change activity with respect to said item;

generating and storing a stored checksum of sequence indicia generated only for said first subset of items which are content items, and not for said non-content items; and

responsive to a refresh operation with respect to said child place, calculating a refresh checksum of sequence indicia for said content items; and

said central refresh execution module further responsive to said stored checksum and said refresh checksum being unequal for refreshing said child place.

14. The system of claim 13, said central refresh execution module further for:

determining whether a place object is inherited from its place type or created in said child place by a place user;

determining whether an inherited place object is modified in a place;

determining whether a place object which exists in said source place, but not in said child place, is new to said child place or is deleted in said child place by said place user;

executing a central refresh process as selectively choosing either a basic refresh or a replace process with respect to place objects;

wherein choosing a basic refresh process comprises updating and deleting only place objects not previously changed in said place which have been changed or deleted in its corresponding place type, and leaving unchanged all other place objects; and

wherein choosing a replace process comprises leaving objects unchanged for objects not changed in place or in place type and objects deleted from both place and place type, updating objects changed in place whether or not changed in place type, updating objects changed in place type and not changed in place, for objects deleted in place copying back objects from place type whether or not changed, deleting objects from place which have been deleted from place type.

15. The system of claim 14, said central refresh execution module further for determining whether a place object is inherited from its place type or created in said child place by a place user by:

appending replaced indicia to object notes used to label inherited objects; and

during refresh, identifying objects not having said replaced indicia as local objects which have been created in said child place by said place user.

16. The system of claim 15, said replaced indicia being a time stamp that records last refresh/replace time of each said note;

and said central refresh execution module further for determining with reference to said last refresh/replace time if a source object has changed since a last refresh.

17. The system of claim 16, said central refresh execution module determining whether a place object which exists in said source place, but not in said child place, is new to said child place or is deleted in said child place by said place user by:

comparing a creation date of place object with a refresh date of said place stored in a place type stamp;

responsive to said creation date not being earlier than said refresh date, adding said new object to said child place; and

responsive to said creation date being earlier than said refresh date, for basic refresh not adding said new object to said child place.

18. The system of claim 13, said central refresh execution module further for distributing quick place changes in a clustered environment by:

on a first server, pulling updates from a source place to its corresponding place type;

on said first server, centrally pushing place type updates from said place type to its dependent child places on said first server; and

replicating said places on said first server to a second server in a cluster including said first server.

19. A storage medium readable by a machine, embodying a program of instructions executable by a machine to perform method steps for central refresh of a place, said method comprising:

providing a place type as a template derived from design elements and content elements of a source place;

deriving from said place type a least one child place;

each said child place including a plurality of objects implemented as documents, logic and design notes, said design notes including a plurality of items including a first subset of said items which are content items descriptive of content of said objects and a second subset of said items which are non-content items;

determining whether an inherited place object is modified in a place by

assigning to each of said plurality of items a sequence indicia indicative of change activity with respect to said item;

generating and storing a stored checksum of sequence indicia generated only for said first subset of said items which are content items; and

responsive to a refresh operation with respect to said child place, calculating a refresh checksum of sequence indicia for said content items; and

responsive to said stored checksum and said refresh checksum being unequal, refreshing said child place.

20. The storage medium of claim 19, said method further comprising:

associating algorithm version indicia with each of said refresh checksum and said stored checksum;

responsive to said version indicia being unequal, adapting comparison of said refresh checksum and said stored checksum to differences in associated algorithms.

21. The storage medium of claim 19, said method further comprising incrementing item sequence numbers and recalculating and updating said stored checksum each time said note is refreshed.

22. The storage medium of claim 21, said method further comprising:

executing a hierarchical inheritance process by selectively pulling updates from said source place to said place type and pulling updates from said place type to said child place, and pushing updates from said place type selectively to all or specified child places residing on a same server with said place type.

23. The storage medium of claim 21, said refreshing further comprising iterating through all objects contained in said child place and refreshing all the objects inherited from said place type while not refreshing objects created in said child place by a user.

24. The storage medium of claim 23, said refreshing further comprising not refreshing objects which are members and groups.

25. The storage medium of claim 23, said method further comprising

determining whether a place object is inherited from its place type or created in said child place by a place user;

determining whether an inherited place object is modified in a place;

determining whether a place object which exists in said source place, but not in said child place, is new to said child place or is deleted in said child place by said place user;

executing a central refresh process as selectively choosing either a basic refresh or a replace process with respect to place objects;

wherein choosing a basic refresh process comprises updating and deleting only place objects not previously changed in said place which have been changed or deleted in its corresponding place type, and leaving unchanged all other place objects; and

wherein choosing a replace process comprises leaving objects unchanged for objects not changed in place or in place type and objects deleted from both place and place type, updating objects changed in place whether or not changed in place type, updating objects changed in place type and not changed in place, for objects deleted in place copying back objects from place type whether or not changed, deleting objects from place which have been deleted from place type.

26. The storage medium of claim 25, said determining whether a place object is inherited from its place type or created in said child place by a place user comprising:

appending replaced indicia to object notes used to label inherited objects; and

during refresh, identifying objects not having said replaced indicia as local objects which have been created in said child place by said place user.

27. The storage medium of claim 26, said replaced indicia being a time stamp that records last refresh/replace time of each said note;

and said method further comprising determining with reference to said last refresh/replace, time whether a source object has changed since a last refresh.

28. The storage medium of claim 26, said determining whether a place object which exists in said source place, but not in said child place, is new to said child place or is deleted in said child place by said place user comprising:

comparing a creation date of place object with a refresh date of said place stored in a place type stamp;

responsive to said creation date not being earlier than said refresh date, adding said new object to said child place; and

responsive to said creation date being earlier than said refresh date, for basic refresh not adding said new object to said child place.

29. The storage medium of claim 19, said method further comprising distributing quick place changes in a clustered environment by:

on a first server, pulling updates from a source place to its corresponding place type;

on said first server, centrally pushing place type updates from said place type to its dependent child places on said first server; and

replicating said places on said first server to a second server in a cluster including said first server.

30. The storage medium of claim 29, said method further comprising pulling updates to child places on said second server from a place type replica on said second server of a place type on said first server.

31. A computer program product, residing on a computer readable storage medium, for central refresh of a place according to the method comprising:

providing a place type as a template derived from design elements and content elements of a source place;

deriving from said place type a least one child place;

each said child place including a plurality of objects implemented as documents, logic and design notes, said design notes including a plurality of items including a first subset of said items which are content items descriptive of content of said objects and a second subset of said items which are non-content items;

determining whether an inherited place object is modified in a place by

assigning to each of said plurality of items a sequence indicia indicative of change activity with respect to said item;

generating and storing a stored checksum of sequence indicia generated only for said first subset of items which are content items; and

responsive to a refresh operation with respect to said child place, calculating a refresh checksum of sequence indicia for said content items; and

responsive to said stored checksum and said refresh checksum being unequal, refreshing said child place.