Package org.apache.lucene.geo

package org.apache.lucene.geo

Core geo-spatial types and utilities for handling geographical data and spatial operations in Lucene.

Overview

This package provides classes for representing, indexing, and querying geographical data in Lucene. It uses the WGS84 coordinate system with latitude/longitude pairs to represent points on Earth.

Core Concepts

• Coordinate System: WGS84 (World Geodetic System 1984)
  • Latitude: -90° to +90° (negative for South, positive for North)
  • Longitude: -180° to +180° (negative for West, positive for East)
• Distance calculations use haversine formula on a spherical Earth model
• Areas near poles and the dateline receive special handling

Key Components

• Point: Represents a point on Earth's surface
• Rectangle: Defines a bounding box for spatial queries
• Circle: Represents a circular area with a center point and radius
• Polygon: Represents an arbitrary polygon shape
• Line: Represents a path or line string

Common Operations

• Distance calculations between points
• Point-in-polygon testing
• Rectangle containment and intersection
• Creation of bounding boxes
• Polygon validation and preprocessing

Usage Examples

 Rectangle bbox = Rectangle.fromPointDistance(51.5, -0.12, 5000); // 5km around London
 Circle circle = new Circle(48.8566, 2.3522, 1000); // 1km around Paris
 

Class	Description
Circle	Represents a circle on the Earth's surface defined by a center point and radius.
Component2D	2D Geometry object that supports spatial relationships with bounding boxes, triangles and points.
Component2D.WithinRelation	Used by withinTriangle to check the within relationship between a triangle and the query shape (e.g.
GeoEncodingUtils	reusable geopoint encoding methods
GeoEncodingUtils.Component2DPredicate	A predicate that checks whether a given point is within a component2D geometry.
GeoEncodingUtils.DistancePredicate	A predicate that checks whether a given point is within a distance of another point.
Geometry	Base class for LatLonGeometry and XYGeometry
GeoUtils	Utility methods for geo-spatial calculations and coordinate validation.
GeoUtils.WindingOrder	used to define the orientation of 3 points -1 = Clockwise 0 = Colinear 1 = Counter-clockwise
LatLonGeometry	Lat/Lon Geometry object.
Line	Represents a line on the earth's surface.
Point	Represents a point on the earth's surface.
Polygon	Represents a closed polygon on the earth's surface.
Rectangle	Represents a rectangular bounding box on Earth's surface.
SimpleWKTShapeParser	Parses shape geometry represented in WKT format
SimpleWKTShapeParser.ShapeType	Enumerated type for Shapes
Tessellator	Computes a triangular mesh tessellation for a given polygon.
Tessellator.Monitor	Implementation of this interface will receive calls with internal data at each step of the triangulation algorithm.
Tessellator.Triangle	Triangle in the tessellated mesh
XYCircle	Represents a circle on the XY plane.
XYEncodingUtils	reusable cartesian geometry encoding methods
XYGeometry	Cartesian Geometry object.
XYLine	Represents a line in cartesian space.
XYPoint	Represents a point on the earth's surface.
XYPolygon	Represents a polygon in cartesian space.
XYRectangle	Represents a x/y cartesian rectangle.