001/*
002 * Copyright 2006 - 2013
003 *     Stefan Balev     <stefan.balev@graphstream-project.org>
004 *     Julien Baudry    <julien.baudry@graphstream-project.org>
005 *     Antoine Dutot    <antoine.dutot@graphstream-project.org>
006 *     Yoann Pigné      <yoann.pigne@graphstream-project.org>
007 *     Guilhelm Savin   <guilhelm.savin@graphstream-project.org>
008 * 
009 * This file is part of GraphStream <http://graphstream-project.org>.
010 * 
011 * GraphStream is a library whose purpose is to handle static or dynamic
012 * graph, create them from scratch, file or any source and display them.
013 * 
014 * This program is free software distributed under the terms of two licenses, the
015 * CeCILL-C license that fits European law, and the GNU Lesser General Public
016 * License. You can  use, modify and/ or redistribute the software under the terms
017 * of the CeCILL-C license as circulated by CEA, CNRS and INRIA at the following
018 * URL <http://www.cecill.info> or under the terms of the GNU LGPL as published by
019 * the Free Software Foundation, either version 3 of the License, or (at your
020 * option) any later version.
021 * 
022 * This program is distributed in the hope that it will be useful, but WITHOUT ANY
023 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
024 * PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more details.
025 * 
026 * You should have received a copy of the GNU Lesser General Public License
027 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
028 * 
029 * The fact that you are presently reading this means that you have had
030 * knowledge of the CeCILL-C and LGPL licenses and that you accept their terms.
031 */
032package org.graphstream.util;
033
034import java.util.Iterator;
035
036import org.graphstream.graph.Graph;
037import org.graphstream.graph.Node;
038
039public class FilteredNodeIterator<T extends Node> implements Iterator<T> {
040
041        protected Iterator<T> globalIterator;
042        protected Filter<Node> filter;
043        protected T next;
044
045        public FilteredNodeIterator(Graph g, Filter<Node> filter) {
046                this(g.<T>getNodeIterator(), filter);
047        }
048        
049        public FilteredNodeIterator(Iterator<T> ite, Filter<Node> filter) {
050                this.globalIterator = ite;
051                this.filter = filter;
052
053                findNext();
054        }
055
056        protected void findNext() {
057                next = null;
058
059                while (globalIterator.hasNext() && next == null) {
060                        next = globalIterator.next();
061
062                        if (!filter.isAvailable(next))
063                                next = null;
064                }
065        }
066
067        /*
068         * (non-Javadoc)
069         * @see java.util.Iterator#hasNext()
070         */
071        public boolean hasNext() {
072                return next != null;
073        }
074
075        /*
076         * (non-Javadoc)
077         * @see java.util.Iterator#next()
078         */
079        public T next() {
080                T tmp = next;
081                findNext();
082
083                return tmp;
084        }
085
086        /*
087         * (non-Javadoc)
088         * @see java.util.Iterator#remove()
089         */
090        public void remove() {
091        }
092}