Module org.jgrapht.osm

Package org.jgrapht.osm

Class OsmCsvGraphLoader

java.lang.Object

org.jgrapht.osm.OsmCsvGraphLoader

public final class OsmCsvGraphLoader
extends Object

Loads a headerless weighted edge-list CSV (the format produced by GpkgRoadGraphPreprocessor) into a target Graph. The actual parsing is delegated to CSVImporter from jgrapht-io; this class only adds gzip support and the conventional Integer-vertex factory.

CSV schema (one directed edge per line, no header):

 src,dst,weight_m
 

Vertices are created on demand from the CSV tokens via Integer::valueOf. Callers that need a different vertex type can build their own CSVImporter directly; this class is a convenience for the OSM road-graph case.

Author:

Shai Eilat

Method Summary

Modifier and Type	Method	Description
static Graph<Integer,DefaultWeightedEdge>	loadGzipped(InputStream gzippedCsv)	Loads the gzipped edges stream into a freshly created SimpleDirectedWeightedGraph<Integer, DefaultWeightedEdge>.
static Graph<Integer,DefaultWeightedEdge>	loadGzippedFile(Path path)	Loads the gzipped edges file into a freshly created SimpleDirectedWeightedGraph<Integer, DefaultWeightedEdge>.
static void	loadGzippedInto(InputStream gzippedCsv, Graph<Integer,DefaultWeightedEdge> graph)	Loads the gzipped edges stream into the caller-supplied graph.
static Graph<Integer,DefaultWeightedEdge>	loadGzippedResource(Class<?> anchor, String resource)	Loads the gzipped edges resource into a freshly created SimpleDirectedWeightedGraph<Integer, DefaultWeightedEdge>.

Methods inherited from class java.lang.Object

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

Method Details

loadGzippedResource

public static Graph<Integer,DefaultWeightedEdge> loadGzippedResource(Class<?> anchor,
 String resource)
                                                              throws IOException

Loads the gzipped edges resource into a freshly created SimpleDirectedWeightedGraph<Integer, DefaultWeightedEdge>. Reads directly from a classpath resource looked up relative to the given anchor class.

Parameters:

anchor - anchor class for Class.getResourceAsStream(java.lang.String)

resource - resource path (must point at a gzipped CSV)

Returns:

the loaded graph

Throws:

IOException - on missing resource or parse error

loadGzippedFile

public static Graph<Integer,DefaultWeightedEdge> loadGzippedFile(Path path)
                                                          throws IOException

Loads the gzipped edges file into a freshly created SimpleDirectedWeightedGraph<Integer, DefaultWeightedEdge>.

Parameters:

path - file path (must point at a gzipped CSV)

Returns:

the loaded graph

Throws:

IOException - on parse error

loadGzipped

public static Graph<Integer,DefaultWeightedEdge> loadGzipped(InputStream gzippedCsv)
                                                      throws IOException

Loads the gzipped edges stream into a freshly created SimpleDirectedWeightedGraph<Integer, DefaultWeightedEdge>. The caller closes the stream.

Parameters:

gzippedCsv - gzipped CSV input stream

Returns:

the loaded graph

Throws:

IOException - on parse error

loadGzippedInto

public static void loadGzippedInto(InputStream gzippedCsv,
 Graph<Integer,DefaultWeightedEdge> graph)
                            throws IOException

Loads the gzipped edges stream into the caller-supplied graph. Useful when the caller has pre-added vertices in a specific order, or wants a different graph concrete type (e.g. a directed multigraph).

Parameters:

gzippedCsv - gzipped CSV input stream (caller closes)

graph - the destination graph

Throws:

IOException - on parse error