com.graphhopper.routing.util

Enum TraversalMode

java.lang.Object

java.lang.Enum<TraversalMode>

com.graphhopper.routing.util.TraversalMode

All Implemented Interfaces:

Serializable, Comparable<TraversalMode>

public enum TraversalMode
extends Enum<TraversalMode>

Defines how the graph can be traversed while Dijkstra or similar RoutingAlgorithm is in progress. Different options define how precise turn restrictions and costs are taken into account, but still all are without via-way support. BTW: this would not be done at runtime, this would be a pre-processing step to avoid performance penalties.

Author:

Peter Karich

Enum Constant Summary

Enum Constants

Enum Constant and Description
EDGE_BASED_2DIR The bidirectional edged-based traversal mode with turn restriction and cost support.
EDGE_BASED_2DIR_UTURN Not recommended as it leads to strange routes that outsmart the turn costs.
NODE_BASED The simplest traversal mode but without turn restrictions or cost support.

Method Summary

Modifier and Type	Method and Description
int	createTraversalId(EdgeIteratorState iterState, boolean reverse) Returns the identifier to access the map of the shortest path tree according to the traversal mode.
int	createTraversalId(int baseNode, int adjNode, int edgeId, boolean reverse) If you have an EdgeIteratorState the other createTraversalId is preferred!
static TraversalMode	fromString(String name)
boolean	hasUTurnSupport()
boolean	isEdgeBased()
int	reverseEdgeKey(int edgeKey)
static TraversalMode	valueOf(String name) Returns the enum constant of this type with the specified name.
static TraversalMode[]	values() Returns an array containing the constants of this enum type, in the order they are declared.

Methods inherited from class java.lang.Enum

clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Enum Constant Detail

NODE_BASED

public static final TraversalMode NODE_BASED

The simplest traversal mode but without turn restrictions or cost support.

EDGE_BASED_2DIR

public static final TraversalMode EDGE_BASED_2DIR

The bidirectional edged-based traversal mode with turn restriction and cost support. Without u-turn support. 2 times slower than node based.

EDGE_BASED_2DIR_UTURN

public static final TraversalMode EDGE_BASED_2DIR_UTURN

Not recommended as it leads to strange routes that outsmart the turn costs. The most feature rich edge-based traversal mode with turn restriction and cost support, including u-turns. 4 times slower than node based.

Method Detail

values

public static TraversalMode[] values()

Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:

for (TraversalMode c : TraversalMode.values())
    System.out.println(c);

Returns:

an array containing the constants of this enum type, in the order they are declared

valueOf

public static TraversalMode valueOf(String name)

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:

name - the name of the enum constant to be returned.

Returns:

the enum constant with the specified name

Throws:

IllegalArgumentException - if this enum type has no constant with the specified name

NullPointerException - if the argument is null

fromString

public static TraversalMode fromString(String name)

createTraversalId

public final int createTraversalId(EdgeIteratorState iterState,
                                   boolean reverse)

Returns the identifier to access the map of the shortest path tree according to the traversal mode. E.g. returning the adjacent node id in node-based behavior whilst returning the edge id in edge-based behavior

Parameters:

iterState - the current EdgeIteratorState

reverse - true, if traversal in backward direction. Will be true only for backward searches in bidirectional algorithms.

Returns:

the identifier to access the shortest path tree

createTraversalId

public final int createTraversalId(int baseNode,
                                   int adjNode,
                                   int edgeId,
                                   boolean reverse)

If you have an EdgeIteratorState the other createTraversalId is preferred!

reverseEdgeKey

public int reverseEdgeKey(int edgeKey)

isEdgeBased

public boolean isEdgeBased()

hasUTurnSupport

public final boolean hasUTurnSupport()