com.graphhopper.storage.index

Interface LocationIndex

All Superinterfaces:

AutoCloseable, Closeable, Storable<LocationIndex>

All Known Implementing Classes:

Location2IDFullIndex, Location2IDFullWithEdgesIndex, LocationIndexTree

public interface LocationIndex
extends Storable<LocationIndex>

Provides a way to map real world data "lat,lon" to internal ids/indices of a memory efficient graph - often just implemented as an array.

The implementations of findID needs to be thread safe!

Author:

Peter Karich

Method Summary

Modifier and Type	Method and Description
QueryResult	findClosest(double lat, double lon, EdgeFilter edgeFilter) This method returns the closest QueryResult for the specified location (lat, lon) and only if the filter accepts the edge as valid candidate (e.g.
LocationIndex	prepareIndex() Creates this index - to be called once before findID.
LocationIndex	setApproximation(boolean approxDist)
LocationIndex	setResolution(int resolution) Integer value to specify the resolution of this location index.
void	setSegmentSize(int bytes)

Methods inherited from interface com.graphhopper.storage.Storable

close, create, flush, getCapacity, isClosed, loadExisting

Method Detail

setResolution

LocationIndex setResolution(int resolution)

Integer value to specify the resolution of this location index. The higher the better the resolution.

prepareIndex

LocationIndex prepareIndex()

Creates this index - to be called once before findID.

findClosest

QueryResult findClosest(double lat,
                        double lon,
                        EdgeFilter edgeFilter)

This method returns the closest QueryResult for the specified location (lat, lon) and only if the filter accepts the edge as valid candidate (e.g. filtering away car-only results for bike search)

Parameters:

edgeFilter - if a graph supports multiple vehicles we have to make sure that the entry node into the graph is accessible from a selected vehicle. E.g. if you have a FOOT-query do:

new DefaultEdgeFilter(footFlagEncoder);

Returns:

An object containing the closest node and edge for the specified location. The node id has at least one edge which is accepted from the specified edgeFilter. If nothing is found the method QueryResult.isValid will return false.

setApproximation

LocationIndex setApproximation(boolean approxDist)

Parameters:

approxDist - false if initialization and querying should be faster but less precise.

setSegmentSize

void setSegmentSize(int bytes)