Class MapGraph

java.lang.Object

MapGraph

All Implemented Interfaces:

AStarGraph<org.locationtech.spatial4j.shape.Point>, Graph<org.locationtech.spatial4j.shape.Point>

public class MapGraph
extends Object
implements AStarGraph<org.locationtech.spatial4j.shape.Point>

AStarGraph of places as Point vertices and streets edges weighted by physical distance.

See Also:

AStarGraph, MapServer

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private class	MapGraph.Handler	Parses OSM XML files to construct a MapGraph.

Field Summary

Fields

Modifier and Type	Field	Description
private Autocomplete	autocomplete
private org.locationtech.spatial4j.context.SpatialContext	context
private Map<CharSequence,Integer>	importance
private Map<String,List<org.locationtech.spatial4j.shape.Point>>	locations
private Map<org.locationtech.spatial4j.shape.Point,List<Edge<org.locationtech.spatial4j.shape.Point>>>	neighbors
private String	osmPath
private String	placesPath

Constructor Summary

Constructors

Constructor	Description
MapGraph(String osmPath, String placesPath, org.locationtech.spatial4j.context.SpatialContext context)	Constructs a new map graph from the path to an OSM GZ file and a places TSV.

Method Summary

Modifier and Type	Method	Description
private void	addEdge(org.locationtech.spatial4j.shape.Point from, org.locationtech.spatial4j.shape.Point to)	Adds an edge to this graph if it doesn't already exist using distance as the weight.
private Comparator<org.locationtech.spatial4j.shape.Point>	byEstimatedDistanceFrom(org.locationtech.spatial4j.shape.Point start)	Returns a Comparator by estimated distance from the given start point.
org.locationtech.spatial4j.shape.Point	closest(org.locationtech.spatial4j.shape.Point target)	Returns the location closest to the given target location.
double	estimatedDistance(org.locationtech.spatial4j.shape.Point start, org.locationtech.spatial4j.shape.Point end)	Returns an estimated distance from start to end.
private static InputStream	fileStream(String path)	Returns an input stream from the contents of the file at the given path.
List<org.locationtech.spatial4j.shape.Point>	getLocations(String locationName, org.locationtech.spatial4j.shape.Point center)	Return all locations that match a valid location name.
List<CharSequence>	getLocationsByPrefix(String prefix)	Return the names of all locations that prefix-match the query string.
List<Edge<org.locationtech.spatial4j.shape.Point>>	neighbors(org.locationtech.spatial4j.shape.Point point)	Returns a list of the outgoing edges from the given vertex.
List<org.locationtech.spatial4j.shape.Point>	shortestPath(org.locationtech.spatial4j.shape.Point start, org.locationtech.spatial4j.shape.Point goal)	Returns a list of points representing the shortest path from the points closest to the start and goal.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

osmPath

private final String osmPath

placesPath

private final String placesPath

context

private final org.locationtech.spatial4j.context.SpatialContext context

neighbors

private final Map<org.locationtech.spatial4j.shape.Point,List<Edge<org.locationtech.spatial4j.shape.Point>>> neighbors

locations

private final Map<String,List<org.locationtech.spatial4j.shape.Point>> locations

autocomplete

private final Autocomplete autocomplete

importance

private final Map<CharSequence,Integer> importance

Constructor Detail

MapGraph

public MapGraph(String osmPath,
                String placesPath,
                org.locationtech.spatial4j.context.SpatialContext context)
         throws ParserConfigurationException,
                SAXException,
                IOException

Constructs a new map graph from the path to an OSM GZ file and a places TSV.

Parameters:

osmPath - The path to a gzipped OSM (XML) file.

placesPath - The path to a TSV file representing places and importance.

Throws:

ParserConfigurationException - if a parser cannot be created.

SAXException - for SAX errors.

IOException - if a file is not found or if the file is not gzipped.

Method Detail

fileStream

private static InputStream fileStream(String path)

Returns an input stream from the contents of the file at the given path.

Parameters:

path - a file path.

Returns:

an input stream with the contents of the specified file.

closest

public org.locationtech.spatial4j.shape.Point closest(org.locationtech.spatial4j.shape.Point target)

Returns the location closest to the given target location.

Parameters:

target - the target location.

Returns:

the id of the location closest to the target.

getLocationsByPrefix

public List<CharSequence> getLocationsByPrefix(String prefix)

Return the names of all locations that prefix-match the query string.

Parameters:

prefix - prefix string that could be any case with or without punctuation.

Returns:

a list of full names of locations matching the prefix.

getLocations

public List<org.locationtech.spatial4j.shape.Point> getLocations(String locationName,
                                                                 org.locationtech.spatial4j.shape.Point center)

Return all locations that match a valid location name.

Parameters:

locationName - a full name of a valid location.

Returns:

a list of locations whose name matches the location name.

shortestPath

public List<org.locationtech.spatial4j.shape.Point> shortestPath(org.locationtech.spatial4j.shape.Point start,
                                                                 org.locationtech.spatial4j.shape.Point goal)

Returns a list of points representing the shortest path from the points closest to the start and goal.

Parameters:

start - the Point to start the shortest path.

goal - the Point to end the shortest path.

Returns:

a list of points representing the shortest path from the points closest to the start and goal.

neighbors

public List<Edge<org.locationtech.spatial4j.shape.Point>> neighbors(org.locationtech.spatial4j.shape.Point point)

Description copied from interface: Graph

Returns a list of the outgoing edges from the given vertex.

Specified by:

neighbors in interface Graph<org.locationtech.spatial4j.shape.Point>

Parameters:

point - the node of interest.

Returns:

a list of the outgoing edges from the given vertex.

estimatedDistance

public double estimatedDistance(org.locationtech.spatial4j.shape.Point start,
                                org.locationtech.spatial4j.shape.Point end)

Description copied from interface: AStarGraph

Returns an estimated distance from start to end.

Specified by:

estimatedDistance in interface AStarGraph<org.locationtech.spatial4j.shape.Point>

Parameters:

start - the beginning vertex.

end - the destination vertex.

Returns:

an estimated distance from start to end.

toString

public String toString()

Overrides:

toString in class Object

addEdge

private void addEdge(org.locationtech.spatial4j.shape.Point from,
                     org.locationtech.spatial4j.shape.Point to)

Adds an edge to this graph if it doesn't already exist using distance as the weight.

Parameters:

from - the originating point of the edge.

to - the terminating point of the edge.

byEstimatedDistanceFrom

private Comparator<org.locationtech.spatial4j.shape.Point> byEstimatedDistanceFrom(org.locationtech.spatial4j.shape.Point start)

Returns a Comparator by estimated distance from the given start point.

Parameters:

start - the given start point for distance comparison.

Returns:

a Comparator by estimated distance from the given start point.