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/* * Copyright (C) 2012 W. Patrick Hooper <wphooper@gmail.com> * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program 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 General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ package path; import geometry.LineSegment; /** * An EdgeIterator is an object which iterates over edges in a PolygonalPath. * We have based the interface on java.util.Iterator. * * We have chosen to make our own class rather than use Java's built in * Iterator<T> class for simplicity and because the PathIterator class will * extend this one. * * <em>Technical discussion:</em> We can't do exactly this with Java's built * in Iterator class, because Iterator<Path> does not extend Iterator<Segment>. * It is true that Iterator<? extends Path> extends Iterator<? extends Segment>, * so this is another possible approach. But, this approach seems to be overly * technical for an introduction to java. * * @see java.util.Iterator Java's Iterator<T> interface * @see path.PathIterator The PathIterator interface, which extends EdgeIterator * @author W. Patrick Hooper <wphooper@gmail.com> */ public interface EdgeIterator { /** * Return true when the iterator will return another edge with a call to * next(). Returns false otherwise. */ public boolean hasNext(); /** * Return the next segment. */ public LineSegment next(); }