Class ComponentCoordinateExtracter

1
2	/*
3	* Copyright (c) 2016 Vivid Solutions.
4	*
5	* All rights reserved. This program and the accompanying materials
6	* are made available under the terms of the Eclipse Public License 2.0
7	* and Eclipse Distribution License v. 1.0 which accompanies this distribution.
8	* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v20.html
9	* and the Eclipse Distribution License is available at
10	*
11	* http://www.eclipse.org/org/documents/edl-v10.php.
12	*/
13	package org.locationtech.jts.geom.util;
14
15	import java.util.ArrayList;
16	import java.util.List;
17
18	import org.locationtech.jts.geom.Coordinate;
19	import org.locationtech.jts.geom.Geometry;
20	import org.locationtech.jts.geom.GeometryComponentFilter;
21	import org.locationtech.jts.geom.LineString;
22	import org.locationtech.jts.geom.Point;
23
24	/**
25	* Extracts a representative {@link Coordinate}
26	* from each connected component of a {@link Geometry}.
27	*
28	* @version 1.9
29	*/
30	public class ComponentCoordinateExtracter
31	implements GeometryComponentFilter
32	{
33
34	/**
35	* Extracts a representative {@link Coordinate}
36	* from each connected component in a geometry.
37	* <p>
38	* If more than one geometry is to be processed, it is more
39	* efficient to create a single {@link ComponentCoordinateExtracter} instance
40	* and pass it to each geometry.
41	*
42	* @param geom the Geometry from which to extract
43	* @return a list of representative Coordinates
44	*/
45	public static List getCoordinates(Geometry geom)
46	{
47	List coords = new ArrayList();
48	geom.apply(new ComponentCoordinateExtracter(coords));
49	return coords;
50	}
51
52	private List coords;
53
54	/**
55	* Constructs a LineExtracterFilter with a list in which to store LineStrings found.
56	*/
57	public ComponentCoordinateExtracter(List coords)
58	{
59	this.coords = coords;
60	}
61
62	public void filter(Geometry geom)
63	{
64	// add coordinates from connected components
65	if (geom instanceof LineString
66	\|\| geom instanceof Point)
67	coords.add(geom.getCoordinate());
68	}
69
70	}
71