Class LineMergeDirectedEdge

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.operation.linemerge;
14
15	import org.locationtech.jts.geom.Coordinate;
16	import org.locationtech.jts.planargraph.DirectedEdge;
17	import org.locationtech.jts.planargraph.Node;
18	import org.locationtech.jts.util.Assert;
19
20	/**
21	* A {@link org.locationtech.jts.planargraph.DirectedEdge} of a
22	* {@link LineMergeGraph}.
23	*
24	* @version 1.7
25	*/
26	public class LineMergeDirectedEdge extends DirectedEdge {
27	/**
28	* Constructs a LineMergeDirectedEdge connecting the <code>from</code> node to the
29	* <code>to</code> node.
30	*
31	* @param directionPt
32	* specifies this DirectedEdge's direction (given by an imaginary
33	* line from the <code>from</code> node to <code>directionPt</code>)
34	* @param edgeDirection
35	* whether this DirectedEdge's direction is the same as or
36	* opposite to that of the parent Edge (if any)
37	*/
38	public LineMergeDirectedEdge(Node from, Node to, Coordinate directionPt,
39	boolean edgeDirection) {
40	super(from, to, directionPt, edgeDirection);
41	}
42
43	/**
44	* Returns the directed edge that starts at this directed edge's end point, or null
45	* if there are zero or multiple directed edges starting there.
46	* @return the directed edge
47	*/
48	public LineMergeDirectedEdge getNext() {
49	if (getToNode().getDegree() != 2) {
50	return null;
51	}
52	if (getToNode().getOutEdges().getEdges().get(0) == getSym()) {
53	return (LineMergeDirectedEdge) getToNode().getOutEdges().getEdges().get(1);
54	}
55	Assert.isTrue(getToNode().getOutEdges().getEdges().get(1) == getSym());
56
57	return (LineMergeDirectedEdge) getToNode().getOutEdges().getEdges().get(0);
58	}
59	}
60