Minimal Ownership for Active Objects

  • Dave Clarke
  • Tobias Wrigstad
  • Johan Östlund
  • Einar Broch Johnsen
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5356)


Active objects offer a structured approach to concurrency, encapsulating both unshared state and a thread of control. For efficient data transfer, data should be passed by reference whenever possible, but this introduces aliasing and undermines the validity of the active objects. This paper proposes a minimal variant of ownership types that preserves the required race freedom invariant yet enables data transfer by reference between active objects (that is, without copying) in many cases, and a cheap clone operation where copying is necessary. Our approach is general and should be adaptable to several existing active object systems.


Active Object Ownership Type Data Race Unique Reference Passive Object 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Dave Clarke
    • 1
  • Tobias Wrigstad
    • 2
  • Johan Östlund
    • 2
  • Einar Broch Johnsen
    • 3
  1. 1.CWIAmsterdamThe Netherlands
  2. 2.Purdue UniversityUSA
  3. 3.University of OsloNorway

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