// @(#) $Id: TwoWayList.refines-jml,v 1.8 2005/12/24 21:20:31 chalin Exp $

// Copyright (C) 1998, 1999 Iowa State University

// This file is part of JML

// JML is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2, or (at your option)
// any later version.

// JML is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with JML; see the file COPYING.  If not, write to
// the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

// Author:  Clyde Ruby


package org.jmlspecs.samples.list.list3;

//@ refine "TwoWayList.java";

import org.jmlspecs.samples.list.node.TwoWayNode;

// FIXME: adapt this file to non-null-by-default and remove the following modifier.
/*@ nullable_by_default @*/ 
public class TwoWayList extends E_OneWayList { // Doubly Linked List

  //@ protected model TwoWayNode cursorNodeTwoWay;            in cursor;
  //@ protected represents cursorNodeTwoWay <- (TwoWayNode) cursorNode_;

  /*@ also
    @  protected code normal_behavior
    @    requires \same;
    @    accessible theListNode_;
    @    captures \nothing;
    @    callable  new TwoWayNode(Object), firstEntry();
    @*/
  public TwoWayList();

// iteration methods
// -----------------

// NEW iteration methods (for doubly linked list)
// ---------------------
  /*@ also
    @  protected code normal_behavior
    @    requires \same;
    @    accessible lastNode_, cursorNode_, prevCursorNode_;
    @    captures \nothing;
    @    callable isOffFront(), isOffEnd(), lastEntry(),
    @             cursorNodeTwoWay.getPrevNode();
    @*/
   public void decrementCursor();

  /*@ also
    @  protected code normal_behavior
    @    requires \same;
    @    accessible lastNode_;
    @    captures \nothing;
    @    callable lastNode_.getPrevNode();
    @*/
   public void lastEntry();

  /*@ also
    @  protected code normal_behavior
    @    requires \same;
    @    accessible cursorNode_, length_;
    @    captures \nothing;
    @    callable isOffEnd(), isOffFront(), decrementCursor(),
    @             cursorNode_.getNextNode(), incrementCursor(),
    @             cursorNode_.removeNextNode();
    @*/
   public void removeEntry();

  /*@ also
    @  protected code normal_behavior
    @    requires \same;
    @    accessible cursorNode_, length_;
    @    captures newEntry;
    @    callable isOffEnd(), decrementCursor(), 
    @             cursorNode_.insertAfter(Object),
    @             incrementCursor(), cursorNode_.getNextNode(),
    @             super.insertAfterCursor(Object );
    @*/
   public void insertAfterCursor(Object newEntry);

  /*@ also
    @  protected code normal_behavior
    @    requires \same;
    @    accessible cursorNode_, length_;
    @    captures newEntry;
    @    callable isOffFront(), isOffEnd(), insertAfterCursor(Object),
    @             decrementCursor(), incrementCursor();
    @*/
   public void insertBeforeCursor(Object newEntry);

  /*@ also
    @  protected code normal_behavior
    @    requires \same;
    @    accessible theList;
    @    captures theListNode_.entries;
    @    callable new TwoWayList(TwoWayList );
    @*/
   public /*@ non_null @*/ Object clone();

  /*@ also
    @  protected code normal_behavior
    @    requires \same;
    @    accessible theList;
    @    captures theListNode_;
    @    callable new TwoWayIterator(TwoWayNode);
    @*/
   public TwoWayIterator createIterator();

// ***********************************************************
// protected methods

  /*@ also
    @  protected code normal_behavior
    @    requires \same;
    @    accessible othLst.theList, theListNode_, lastNode_;
    @    accessible theListNode_, length_, lastNode_;
    @    captures othLst.theList;
    @    callable firstEntry();
    @    callable firstEntry(), lastNode_.getNextNode();
    @*/
   protected TwoWayList(TwoWayList othLst);
}