Abstract

A multi-user collaborative system in which the contents as well as the current status of other user activity of a shared structured data object representing one or more related structured data objects in the form of data entries can be concurrently accessed by different users respectively at different workstations connected to a common link. The WYSIWIS user interface representation of the shared structured data object includes an ordered listing of such entries that are maintained by the structured data object and various attributes of each listed entry, inter alia, the type and class of entry; the revision number of the shared structured data object; the number of pages and revision number of each structured data object entry; the date of creation and last revision of each such entry; whether an entry can be accessed by a user and, if not, who has prevented such access; whether a local instance of an entry is present on a user's system; and a provision for miscellaneous notes or comments relative to each entry for view by other users. Means is provided for maintaining current information relative to the shared structured object and its entries on a user initiated demand updated basis invoked by a user operation, which operation requires updated information to properly implement the operation. Further, means is provided for locking up one or more data entries by an individual user and thereby prevent access of the locked entries by other users to prevent concurrent editing and other changes to the same entries by two or more users. In this connection, editing or modification cannot be performed by a user until the shared structured data object entry or entries have been locked up. Visual indication as to the locked state of entries and other information relative to the locking user and the time of lock is updated and displayed in the shared structured data object representation present at user workstations when a use invokes a user operation on the shared structured data object or its contents.

Other References

• Garrett, L. N., Smith, K. E., and Meyrowitz, N., "Intermedia: Issues, Strategies, and Tactics in the Design of a Hypermedia Document System," Proceedings of the Conference on Computer-Supported Collaborative Work, Austin, Texas, Dec. 3-5, 1986, pp. 163-174
• Stefik, M., Foster, G., Bobrow, D. G., Kahn, K., Lanning, S., and Suchman, L., "Beyond the Chalkboard: Computer Support for Collaboration and Problem Solving in Meetings," Communications of the ACM, vol. 30, No. 1 (Jan. 1987), pp. 32-47
• Interleaf Technical Publishing Software Reference Manual, Release 3.0, vol. 1, 1986, pp. 15-1-15-18, 16-1-16-19
• I. Greif et al., "Data Sharing in Group Work," Conference on Computer-Supported Cooperative Work, pp. 175-183, Dec. 3, 1986
• Sarin, S. K., Interactive On-Line Conferences, Ph.D. Thesis, M.I.T. Department of Electrical Engineering and Computer Science, May 1984, pp. 3, 47-57, 75-78 and 201-227
• Greif, I., Seliger, R. and Weihl, W., "Atomic Data Abstractions in a Distributed Collaborative Editing System," Proceedings of the ACM Symposium on Principles of Programming Languages, St. Petersburg, Fla., Jan. 1986, pp. 160-172
• Sarin, S. K., and Greif, I., "Computer-Based Real-Time Conferencing Systems," Computer, Oct. 1985, pp. 33-45
• Leblang, D. B. and Chase, Jr., R. P., "Computer-Aided Software Engineering in a Distributed Workstation Environment," in Henderson, P., (Ed.), Proceedings of the ACM SIGSOFT/SIGPLAN Software Engineering Symposium on Practical Software Development Environments, Pittsburgh, Pa., Apr. 23-24, 1984
• Sarin, S. K., and Greif, I., "Software for Interactive On-Line Conferences," Proceedings ACM-SIGOA Conference on Office Information Systems, Toronto, Canada, Jun. 25-27, 1984, pp. 1-29
• Trigg, Randall H., et al., "Supporting Collaboration in Notecards," Conference on Computer-Supported Cooperative Work, Dec. 3, 1986, pp. 153-162
• Aguilar, L., et al., "Architecture for a Multimedia Teleconferencing System," Journal of the ACM, 1986, pp. 126-136
• European Search Report and Annex, Application Number EP 88 31 1268, dated Sep. 16, 1992, transmitted with a Communication dated Sep. 28, 1992
• Lewis, B. T. and Jodges, J. D., "Shared Books: Collaborative Publication Management for an Office Information System," Conference on Office Information Systems, Mar. 23-25, 1988, Palo Alto, Ca., pp. 197-204
• Chu, W. W., "Design Considerations of File Directory Systems for Distributed Databases," Distributed Databases, State of the Art Report, Maidenhead, U.K., 1979, pp. 73-8