01: /*
02: * The JTS Topology Suite is a collection of Java classes that
03: * implement the fundamental operations required to validate a given
04: * geo-spatial data set to a known topological specification.
05: *
06: * Copyright (C) 2001 Vivid Solutions
07: *
08: * This library is free software; you can redistribute it and/or
09: * modify it under the terms of the GNU Lesser General Public
10: * License as published by the Free Software Foundation; either
11: * version 2.1 of the License, or (at your option) any later version.
12: *
13: * This library is distributed in the hope that it will be useful,
14: * but WITHOUT ANY WARRANTY; without even the implied warranty of
15: * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16: * Lesser General Public License for more details.
17: *
18: * You should have received a copy of the GNU Lesser General Public
19: * License along with this library; if not, write to the Free Software
20: * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
21: *
22: * For more information, contact:
23: *
24: * Vivid Solutions
25: * Suite #1A
26: * 2328 Government Street
27: * Victoria BC V8T 5G5
28: * Canada
29: *
30: * (250)385-6040
31: * www.vividsolutions.com
32: */
33: package com.vividsolutions.jtsexample.precision;
34:
35: import java.io.*;
36: import java.util.*;
37: import com.vividsolutions.jts.io.WKTReader;
38: import com.vividsolutions.jts.geom.*;
39: import com.vividsolutions.jts.precision.EnhancedPrecisionOp;
40:
41: /**
42: * Example of using {@link EnhancedPrecisionOp} to avoid robustness problems
43: *
44: * @version 1.7
45: */
46: public class EnhancedPrecisionOpExample {
47: public static void main(String[] args) throws Exception {
48: EnhancedPrecisionOpExample example = new EnhancedPrecisionOpExample();
49: try {
50: example.run();
51: } catch (Exception ex) {
52: ex.printStackTrace();
53: }
54: }
55:
56: private WKTReader reader = new WKTReader();
57:
58: public EnhancedPrecisionOpExample() {
59: }
60:
61: void run() throws Exception {
62: String wkt1, wkt2;
63: // two geometries which cause robustness problems
64: wkt1 = "POLYGON ((708653.498611049 2402311.54647056, 708708.895756966 2402203.47250014, 708280.326454234 2402089.6337791, 708247.896591321 2402252.48269854, 708367.379593851 2402324.00761653, 708248.882609455 2402253.07294874, 708249.523621829 2402244.3124463, 708261.854734465 2402182.39086576, 708262.818392579 2402183.35452387, 708653.498611049 2402311.54647056))";
65: wkt2 = "POLYGON ((708258.754920656 2402197.91172757, 708257.029447455 2402206.56901508, 708652.961095455 2402312.65463437, 708657.068786251 2402304.6356364, 708258.754920656 2402197.91172757))";
66: Geometry g1 = reader.read(wkt1);
67: Geometry g2 = reader.read(wkt2);
68:
69: System.out
70: .println("This call to intersection will throw a topology exception due to robustness problems:");
71: try {
72: Geometry result = g1.intersection(g2);
73: } catch (TopologyException ex) {
74: ex.printStackTrace();
75: }
76:
77: System.out
78: .println("Using EnhancedPrecisionOp allows the intersection to be performed with no errors:");
79: Geometry result = EnhancedPrecisionOp.intersection(g1, g2);
80: System.out.println(result);
81: }
82:
83: }
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