Open Mash Cross Reference
mash/tcl/indiva/imgr/mob-hub.tcl

   # mob-hub.tcl --
   #
   #   A hub is a special kind of node in mob graph that represents 
   #   connections to a group of nodes.
   #
   # Copyright (c) 1996-2002 The Regents of the University of California.
   # All rights reserved.
   #
   # Redistribution and use in source and binary forms, with or without
  # modification, are permitted provided that the following conditions are met:
  #
  # A. Redistributions of source code must retain the above copyright notice,
  #    this list of conditions and the following disclaimer.
  # B. Redistributions in binary form must reproduce the above copyright notice,
  #    this list of conditions and the following disclaimer in the documentation
  #    and/or other materials provided with the distribution.
  # C. Neither the names of the copyright holders nor the names of its
  #    contributors may be used to endorse or promote products derived from this
  #    software without specific prior written permission.
  #
  # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS''
  # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  # ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
  # ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  # DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  # SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  # CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  #
  # @(#) $Header: /usr/mash/src/repository/mash/mash-1/tcl/indiva/imgr/mob-hub.tcl,v 1.2 2002/05/01 17:03:42 weitsang Exp $
  #-
  # Class:
  #   MobHub
  # Description:
  #   MobHub is a dummy node that does not correspond to any media
  #   object in the namespace.  The purpose of a dummy node is to 
  #   reduce the number of edges in a complete bipartite graph (V,V')
  #   from n*m to (n+m).  We link all edges in V to the dummy node,
  #   and link the dummy node to all edges in V'.  
  #
  import Mob
  Class MobHub -superclass Mob
  
  MobHub set id_ 0
  MobHub instproc init { } {
      MobHub instvar id_
      $self next hub$id_
      incr id_
  }
  
  MobHub proc get_ext {} {
      return ""
  }
  MobHub public get_type {} {
      return "hub"
  }
  MobHub public share_readable {} {
      return 1
  }
  MobHub public share_writable {} {
      return 1
  }
  MobHub proc is_hub {name} {
      return [string match hub* $name]
  }