/*

     This file is part of Combean.

     Combean 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 of the License, or

     (at your option) any later version.

     Combean 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 Combean; if not, write to the Free Software

     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

 /*

  * Created on 09.04.2005

  *

  */

 package net.sourceforge.combean.interfaces.graph.alg.spath;

 import net.sourceforge.combean.interfaces.graph.Edge;

 import net.sourceforge.combean.interfaces.graph.Node;

 import net.sourceforge.combean.interfaces.graph.containers.FixedPath;

 import net.sourceforge.combean.interfaces.graph.containers.NodeMap;

 /**

  * Interface for single source shortest path algorithms.

  * 

  * @author schickin

  *

  */

 public interface SingleSourceShortestPathAlg

 <NumType extends Comparable<NumType>>

 extends ShortestPathAlg<NumType> {

     /**

      * Define the source of the shortest paths.

      * 

      * @param s

      */

     void setSource(Node s);

     /**

      * Return the shortest path to a given node (may only be called after

      * the algorithm has been run)

      * 

      * @param t the node to which the shortest path shall be given

      * @return the shortest path to t

      */

     FixedPath getShortestPathTo(Node t);

     /**

      * Return the shortest path distance to a given node (may only be

      * called after the algorithm has been run).

      * 

      * @param t the node to which the shortest path distance shall be given.

      * @return the length of the shortest path to t.

      */

     NumType getDistanceTo(Node t);

     /**

      * Return a NodeMap which maps every node in the graph to its predecessor

      * (or null if no precedessor exists, e.g. for the source or because

      * the node has not been reached by the shortest path algorithm).

      * 

      * @return the predecessor map

      */

     NodeMap<Edge> getPredecessorMap();

     /**

      * Return a NodeMap which contains the shortest distance to the source

      * for every node (or infinity if the node is not reachable from the

      * source).

      * The elements must be of type Comparable. The exact type depends on the

      * subclass of Comparable which is used by the PathAlgebra.

      * 

      * @return the map of shortest distances to the source.

      */

     NodeMap getDistanceMap();

 }