org.opentripplanner.routing.algorithm

Class AStar

java.lang.Object

org.opentripplanner.routing.algorithm.AStar

public class AStar
extends Object

Find the shortest path between graph vertices using A*. A basic Dijkstra search is a special case of AStar where the heuristic is always zero. NOTE this is now per-request scoped, which has caused some threading problems in the past. Always make one new instance of this class per request, it contains a lot of state fields.

Constructor Summary

Constructors

Constructor and Description
AStar()

Method Summary

Modifier and Type	Method and Description
List<GraphPath>	getPathsToTarget() Get a list of final shortest path states that satisfy all criteria for the path search.
ShortestPathTree	getShortestPathTree(RoutingRequest req) Compute SPT using default timeout and termination strategy.
ShortestPathTree	getShortestPathTree(RoutingRequest req, double relTimeoutSeconds) Compute SPT using default termination strategy.
ShortestPathTree	getShortestPathTree(RoutingRequest options, double relTimeoutSeconds, SearchTerminationStrategy terminationStrategy)
ShortestPathTree	getShortestPathTree(RoutingRequest options, double relTimeoutSeconds, SearchTerminationStrategy terminationStrategy, Collection<State> initialStates) Get an SPT, starting from a collection of states
void	setTraverseVisitor(TraverseVisitor traverseVisitor)
void	startSearch(RoutingRequest options, SearchTerminationStrategy terminationStrategy, long abortTime) set up a single-origin search

Methods inherited from class java.lang.Object

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

Constructor Detail

AStar

public AStar()

Method Detail

getShortestPathTree

public ShortestPathTree getShortestPathTree(RoutingRequest req)

Compute SPT using default timeout and termination strategy.

getShortestPathTree

public ShortestPathTree getShortestPathTree(RoutingRequest req,
                                            double relTimeoutSeconds)

Compute SPT using default termination strategy.

startSearch

public void startSearch(RoutingRequest options,
                        SearchTerminationStrategy terminationStrategy,
                        long abortTime)

set up a single-origin search

getShortestPathTree

public ShortestPathTree getShortestPathTree(RoutingRequest options,
                                            double relTimeoutSeconds,
                                            SearchTerminationStrategy terminationStrategy)

Returns:

the shortest path, or null if none is found

getShortestPathTree

public ShortestPathTree getShortestPathTree(RoutingRequest options,
                                            double relTimeoutSeconds,
                                            SearchTerminationStrategy terminationStrategy,
                                            Collection<State> initialStates)

Get an SPT, starting from a collection of states

setTraverseVisitor

public void setTraverseVisitor(TraverseVisitor traverseVisitor)

getPathsToTarget

public List<GraphPath> getPathsToTarget()

Get a list of final shortest path states that satisfy all criteria for the path search.