Classes for virtual topologies

public class Cartcomm extends Intracomm {

  public Object clone() { ... }

  // Topology Constructors

  static public dimsCreate(int nnodes, int [] dims) {...}

  public CartParms get() {...}

  public int rank(int [] coords) {...}

  public int [] coords(int rank) {...}

  public ShiftParms shift(int direction, int disp) {...}

  public Cartcomm sub(boolean [] remainDims) {...}

  public int map(int [] dims, boolean [] periods) {...}
}

public class CartParms {

  // Return type for Cartcomm.get()

  public int [] dims ;
  public booleans [] periods ;
  public int [] coords ; 
}

public class ShiftParms {

  // Return type for Cartcomm.shift()

  public int rankSource ;
  public int rankDest ; 
}

public class Graphcomm extends Intracomm {

  public Object clone() { ... }

  // Topology Constructors

  public GraphParms get() {...}

  public int [] neighbours(int rank) {...}

  public int map(int [] index, int [] edges) {...}
}

public class GraphParms {

  // Return type for Graphcomm.get()

  public int [] index ;
  public int [] edges ; 
}