Class SegmentStringUtil

1	/*
2	* Copyright (c) 2016 Vivid Solutions.
3	*
4	* All rights reserved. This program and the accompanying materials
5	* are made available under the terms of the Eclipse Public License 2.0
6	* and Eclipse Distribution License v. 1.0 which accompanies this distribution.
7	* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v20.html
8	* and the Eclipse Distribution License is available at
9	*
10	* http://www.eclipse.org/org/documents/edl-v10.php.
11	*/
12
13	package org.locationtech.jts.noding;
14
15	import java.util.ArrayList;
16	import java.util.Collection;
17	import java.util.Iterator;
18	import java.util.List;
19
20	import org.locationtech.jts.geom.Coordinate;
21	import org.locationtech.jts.geom.Geometry;
22	import org.locationtech.jts.geom.GeometryFactory;
23	import org.locationtech.jts.geom.LineString;
24	import org.locationtech.jts.geom.MultiLineString;
25	import org.locationtech.jts.geom.util.LinearComponentExtracter;
26
27
28	/**
29	* Utility methods for processing {@link SegmentString}s.
30	*
31	* @author Martin Davis
32	*
33	*/
34	public class SegmentStringUtil
35	{
36	/**
37	* Extracts all linear components from a given {@link Geometry}
38	* to {@link SegmentString}s.
39	* The SegmentString data item is set to be the source Geometry.
40	*
41	* @param geom the geometry to extract from
42	* @return a List of SegmentStrings
43	*/
44	public static List extractSegmentStrings(Geometry geom)
45	{
46	return extractNodedSegmentStrings(geom);
47	}
48
49	/**
50	* Extracts all linear components from a given {@link Geometry}
51	* to {@link SegmentString}s.
52	* The SegmentString data item is set to be the source Geometry.
53	*
54	* @param geom the geometry to extract from
55	* @return a List of SegmentStrings
56	*/
57	public static List extractNodedSegmentStrings(Geometry geom)
58	{
59	List segStr = new ArrayList();
60	List lines = LinearComponentExtracter.getLines(geom);
61	for (Iterator i = lines.iterator(); i.hasNext(); ) {
62	LineString line = (LineString) i.next();
63	Coordinate[] pts = line.getCoordinates();
64	segStr.add(new NodedSegmentString(pts, geom));
65	}
66	return segStr;
67	}
68
69	/**
70	* Converts a collection of {@link SegmentString}s into a {@link Geometry}.
71	* The geometry will be either a {@link LineString} or a {@link MultiLineString} (possibly empty).
72	*
73	* @param segStrings a collection of SegmentStrings
74	* @return a LineString or MultiLineString
75	*/
76	public static Geometry toGeometry(Collection segStrings, GeometryFactory geomFact)
77	{
78	LineString[] lines = new LineString[segStrings.size()];
79	int index = 0;
80	for (Iterator i = segStrings.iterator(); i.hasNext(); ) {
81	SegmentString ss = (SegmentString) i.next();
82	LineString line = geomFact.createLineString(ss.getCoordinates());
83	lines[index++] = line;
84	}
85	if (lines.length == 1) return lines[0];
86	return geomFact.createMultiLineString(lines);
87	}
88
89	public static String toString(List segStrings)
90	{
91	StringBuffer buf = new StringBuffer();
92	for (Iterator i = segStrings.iterator(); i.hasNext(); ) {
93	SegmentString segStr = (SegmentString) i.next();
94	buf.append(segStr.toString());
95	buf.append("\n");
96
97	}
98	return buf.toString();
99	}
100	}
101