/* -*- tab-width: 4 -*-
*
* Electric(tm) VLSI Design System
*
* File: AStarOpenListBase.java
* Written by: Christian Harnisch, Ingo Besenfelder, Michael Neumann (Team 3)
*
* Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
*
* Electric(tm) 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 3 of the License, or
* (at your option) any later version.
*
* Electric(tm) 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 Electric(tm); see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, Mass 02111-1307, USA.
*/
package com.sun.electric.tool.routing.experimentalAStar2.algorithm;
import java.util.Collection;
public interface AStarOpenListBase<T extends AStarNodeBase<T>>
{
/**
* Returns the node with the cheapest total cost, and removes it from the open
* list. <br>
* <br>
* The total cost is the sum of the accurate cost from the start position, and
* the estimated cost to the goal position. Therefore, the cheapest node is
* the most promising candidate for continuing path search.
*
* @return Cheapest node if the list is not empty, <code>null</code>
* otherwise.
*/
public T removeCheapestOpenNode();
/**
* Inserts a node in the list of nodes to be visited later while searching.
*
* @param node The node to add.
*/
public void addNodeToOpenList(T node);
/**
* If contained in the list of nodes to be visited later, the given node is
* removed. Otherwise, the list remains unchanged.
*
* @param node The node to be removed.
*/
public void removeNodeFromOpenList(T node);
/**
* If this position has not yet been visited by the A* search, this method
* returns the node associated with the given position.
*
* @param x X-position of the map to be checked.
* @param y Y-position of the map to be checked.
* @param z Z-position of the map to be checked.
*
* @return A node if one was found, <code>null</code> otherwise.
*/
public T findOpenNode(int x, int y, int z);
/**
* Returns if there are no nodes to be visited.
*
* @return <code>true</code> if there are no nodes left, <code>false</code>
* otherwise.
*/
public boolean isOpenListEmpty();
// /**
// * Empties the open list, and returns a collection of all nodes formerly
// * contained in the open list.
// *
// * @return All nodes formerly in the open list.
// *
// * @deprecated As requested nodes are stored in the map permanently, and never
// * released, dumping all nodes into a list is not necessary any
// * more.
// */
// @Deprecated
// public Collection<T> dumpOpenList();
/**
* Removes all nodes from the open list.
*/
public void clearOpenList();
}