Package org.apache.lucene.demo.facet

Class DistanceFacetsExample

java.lang.Object

org.apache.lucene.demo.facet.DistanceFacetsExample

All Implemented Interfaces:

Closeable, AutoCloseable

public class DistanceFacetsExample
extends Object
implements Closeable

Shows simple usage of dynamic range faceting, using the expressions module to calculate distance.

Field Summary

Fields

Modifier and Type	Field	Description
static final double	EARTH_RADIUS_KM	Mean radius of the Earth in KM
static final double	ORIGIN_LATITUDE	The "home" latitude.
static final double	ORIGIN_LONGITUDE	The "home" longitude.

Constructor Summary

Constructors

Constructor	Description
DistanceFacetsExample()	Empty constructor

Method Summary

Modifier and Type	Method	Description
void	close()
TopDocs	drillDown(DoubleRange range)	User drills down on the specified range.
static Query	getBoundingBoxQuery(double originLat, double originLng, double maxDistanceKM)	Given a latitude and longitude (in degrees) and the maximum great circle (surface of the earth) distance, returns a simple Filter bounding box to "fast match" candidates.
void	index()	Build the example index.
static void	main(String[] args)	Runs the search and drill-down examples and prints the results.
FacetResult	search()	User runs a query and counts facets.

Methods inherited from class java.lang.Object

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

Field Details

ORIGIN_LATITUDE

public static final double ORIGIN_LATITUDE

The "home" latitude.

See Also:

• Constant Field Values

ORIGIN_LONGITUDE

public static final double ORIGIN_LONGITUDE

The "home" longitude.

See Also:

• Constant Field Values

EARTH_RADIUS_KM

public static final double EARTH_RADIUS_KM

Mean radius of the Earth in KM

NOTE: this is approximate, because the earth is a bit wider at the equator than the poles. See http://en.wikipedia.org/wiki/Earth_radius

See Also:

• Constant Field Values

Constructor Details

DistanceFacetsExample

public DistanceFacetsExample()

Empty constructor

Method Details

index

public void index()
           throws IOException

Build the example index.

Throws:

IOException

getBoundingBoxQuery

public static Query getBoundingBoxQuery(double originLat,
 double originLng,
 double maxDistanceKM)

Given a latitude and longitude (in degrees) and the maximum great circle (surface of the earth) distance, returns a simple Filter bounding box to "fast match" candidates.

search

public FacetResult search()
                   throws IOException

User runs a query and counts facets.

Throws:

IOException

drillDown

public TopDocs drillDown(DoubleRange range)
                  throws IOException

User drills down on the specified range.

Throws:

IOException

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException

main

public static void main(String[] args)
                 throws Exception

Runs the search and drill-down examples and prints the results.

Throws:

Exception