/*
* GeoTools - The Open Source Java GIS Toolkit
* http://geotools.org
*
* (C) 2001-2006 Vivid Solutions
* (C) 2001-2008, Open Source Geospatial Foundation (OSGeo)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation;
* version 2.1 of the License.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*/
package org.geotools.geometry.iso.topograph2D;
import java.io.PrintStream;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import org.geotools.geometry.iso.index.SpatialIndex;
import org.geotools.geometry.iso.index.quadtree.Quadtree;
/**
* A EdgeList is a list of Edges. It supports locating edges that are pointwise
* equals to a target edge.
*
* @source $URL$
*/
public class EdgeList {
private List edges = new ArrayList();
/**
* An index of the edges, for fast lookup.
*
* a Quadtree is used, because this index needs to be dynamic (e.g. allow
* insertions after queries). An alternative would be to use an ordered set
* based on the values of the edge coordinates
*
*/
private SpatialIndex index = new Quadtree();
public EdgeList() {
}
/**
* Insert an edge unless it is already in the list
*/
public void add(Edge e) {
edges.add(e);
index.insert(e.getEnvelope(), e);
}
public void addAll(Collection edgeColl) {
for (Iterator i = edgeColl.iterator(); i.hasNext();) {
add((Edge) i.next());
}
}
public List getEdges() {
return edges;
}
// <FIX> fast lookup for edges
/**
* If there is an edge equal to e already in the list, return it. Otherwise
* return null.
*
* @return equal edge, if there is one already in the list null otherwise
*/
public Edge findEqualEdge(Edge e) {
Collection testEdges = index.query(e.getEnvelope());
for (Iterator i = testEdges.iterator(); i.hasNext();) {
Edge testEdge = (Edge) i.next();
if (testEdge.equals(e))
return testEdge;
}
return null;
}
public Iterator iterator() {
return edges.iterator();
}
public Edge get(int i) {
return (Edge) edges.get(i);
}
/**
* If the edge e is already in the list, return its index.
*
* @return index, if e is already in the list -1 otherwise
*/
public int findEdgeIndex(Edge e) {
for (int i = 0; i < edges.size(); i++) {
if (((Edge) edges.get(i)).equals(e))
return i;
}
return -1;
}
public void print(PrintStream out) {
out.print("MULTILINESTRING ( ");
for (int j = 0; j < edges.size(); j++) {
Edge e = (Edge) edges.get(j);
if (j > 0)
out.print(",");
out.print("(");
Coordinate[] pts = e.getCoordinates();
for (int i = 0; i < pts.length; i++) {
if (i > 0)
out.print(",");
out.print(pts[i].x + " " + pts[i].y);
}
out.println(")");
}
out.print(") ");
}
}