Module org.jgrapht.core
Package org.jgrapht.alg.shortestpath

Class BaseBidirectionalShortestPathAlgorithm<V,​E>

java.lang.Object
org.jgrapht.alg.shortestpath.BaseBidirectionalShortestPathAlgorithm<V,​E>
Type Parameters:
V - vertices type
E - edges type
All Implemented Interfaces:
ShortestPathAlgorithm<V,​E>
Direct Known Subclasses:
BidirectionalAStarShortestPath, BidirectionalDijkstraShortestPath
public abstract class BaseBidirectionalShortestPathAlgorithm<V,​E>
extends java.lang.Object
Base class for the bidirectional shortest path algorithms. Currently known extensions are BidirectionalDijkstraShortestPath and BidirectionalAStarShortestPath.
Author:
Dimitrios Michail

  • Nested Class Summary

    Nested classes/interfaces inherited from interface org.jgrapht.alg.interfaces.ShortestPathAlgorithm

    ShortestPathAlgorithm.SingleSourcePaths<V,​E>

  • Field Summary

    Fields 
    Modifier and Type Field Description
    protected Graph<V,​E> graph
    The underlying graph.
    protected static java.lang.String GRAPH_CONTAINS_A_NEGATIVE_WEIGHT_CYCLE
    Error message for reporting the existence of a negative-weight cycle.
    protected static java.lang.String GRAPH_MUST_CONTAIN_THE_SINK_VERTEX
    Error message for reporting that a sink vertex is missing.
    protected static java.lang.String GRAPH_MUST_CONTAIN_THE_SOURCE_VERTEX
    Error message for reporting that a source vertex is missing.

  • Constructor Summary

    Constructors 
    Constructor Description
    BaseBidirectionalShortestPathAlgorithm​(Graph<V,​E> graph)
    Constructs a new instance of the algorithm for a given graph.

  • Method Summary

    Modifier and Type Method Description
    protected GraphPath<V,​E> createEmptyPath​(V source, V sink)
    Create an empty path.
    protected GraphPath<V,​E> createPath​(org.jgrapht.alg.shortestpath.BaseBidirectionalShortestPathAlgorithm.BaseSearchFrontier<V,​E> forwardFrontier, org.jgrapht.alg.shortestpath.BaseBidirectionalShortestPathAlgorithm.BaseSearchFrontier<V,​E> backwardFrontier, double weight, V source, V commonVertex, V sink)
    Builds shortest path between source and sink based on the information provided by search frontiers and common vertex.
    ShortestPathAlgorithm.SingleSourcePaths<V,​E> getPaths​(V source)
    Compute all shortest paths starting from a single source vertex.
    double getPathWeight​(V source, V sink)
    Get the weight of the shortest path from a source vertex to a sink vertex.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    Methods inherited from interface org.jgrapht.alg.interfaces.ShortestPathAlgorithm

    getPath

  • Field Details

  • Constructor Details

  • Method Details

    • createPath

      protected GraphPath<V,​E> createPath​(org.jgrapht.alg.shortestpath.BaseBidirectionalShortestPathAlgorithm.BaseSearchFrontier<V,​E> forwardFrontier, org.jgrapht.alg.shortestpath.BaseBidirectionalShortestPathAlgorithm.BaseSearchFrontier<V,​E> backwardFrontier, double weight, V source, V commonVertex, V sink)
      Builds shortest path between source and sink based on the information provided by search frontiers and common vertex.
      Parameters:
      forwardFrontier - forward direction frontier
      backwardFrontier - backward direction frontier
      weight - weight of the shortest path
      source - path source
      commonVertex - path common vertex
      sink - path sink
      Returns:
      shortest path between source and sink

    • getPaths

      public ShortestPathAlgorithm.SingleSourcePaths<V,​E> getPaths​(V source)
      Compute all shortest paths starting from a single source vertex.
      Specified by:
      getPaths in interface ShortestPathAlgorithm<V,​E>
      Parameters:
      source - the source vertex
      Returns:
      the shortest paths

    • getPathWeight

      public double getPathWeight​(V source, V sink)
      Get the weight of the shortest path from a source vertex to a sink vertex. Returns Double.POSITIVE_INFINITY if no path exists.
      Specified by:
      getPathWeight in interface ShortestPathAlgorithm<V,​E>
      Parameters:
      source - the source vertex
      sink - the sink vertex
      Returns:
      the weight of the shortest path from a source vertex to a sink vertex, or Double.POSITIVE_INFINITY if no path exists

    • createEmptyPath

      protected final GraphPath<V,​E> createEmptyPath​(V source, V sink)
      Create an empty path. Returns null if the source vertex is different than the target vertex.
      Parameters:
      source - the source vertex
      sink - the sink vertex
      Returns:
      an empty path or null null if the source vertex is different than the target vertex