An actor-based metalevel architecture for group-wide reflection

  • Takuo Watanabe
  • Akinori Yonezawa
Technical Contributions
Part of the Lecture Notes in Computer Science book series (LNCS, volume 489)


The notion of group-wide reflection is presented. Group-wide reflection, a dimension of computational reflection in concurrent systems, allows each computational agent (actor/object/process) to reason about and act upon not only the agent itself, but also a group of agents which may contain the agent itself. Global properties of the group can be dynamically controlled through group-wide reflection. We have developed a simple yet general model for group-wide reflection based on the Actor model[1]. An operational semantics of a group of object-level actors is represented by another group of actors (a group of metalevel actors), which is an implementation of a transition system of the object-level group. We prove that the metalevel group correctly represents the operational semantics of the group in terms of transitions of configurations. Furthermore, migration of an actor from node to node is described as an example of group-wide reflection.


reflection group-wide reflection actor model object-oriented concurrent programming object-group ABCL/R ABCL/1 


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Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  1. 1.Department of Information ScienceTokyo Institute of Technology JSPS Fellow (DC)Japan

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