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.graph.implementations; 033 034import java.util.Collections; 035import java.util.HashMap; 036import java.util.Iterator; 037 038import org.graphstream.graph.Edge; 039import org.graphstream.graph.Node; 040 041/** 042 * Nodes used with {@link SingleGraph} 043 * 044 */ 045 046public class SingleNode extends AdjacencyListNode { 047 protected static class TwoEdges { 048 AbstractEdge in, out; 049 } 050 051 protected HashMap<AbstractNode, TwoEdges> neighborMap; 052 053 // *** Constructor *** 054 055 protected SingleNode(AbstractGraph graph, String id) { 056 super(graph, id); 057 neighborMap = new HashMap<AbstractNode, TwoEdges>( 058 4 * INITIAL_EDGE_CAPACITY / 3 + 1); 059 } 060 061 // *** Helpers *** 062 063 @SuppressWarnings("unchecked") 064 @Override 065 protected <T extends Edge> T locateEdge(Node opposite, char type) { 066 TwoEdges ee = neighborMap.get(opposite); 067 if (ee == null) 068 return null; 069 return (T)(type == I_EDGE ? ee.in : ee.out); 070 } 071 072 @Override 073 protected void removeEdge(int i) { 074 AbstractNode opposite = edges[i].getOpposite(this); 075 TwoEdges ee = neighborMap.get(opposite); 076 char type = edgeType(edges[i]); 077 if (type != O_EDGE) 078 ee.in = null; 079 if (type != I_EDGE) 080 ee.out = null; 081 if (ee.in == null && ee.out == null) 082 neighborMap.remove(opposite); 083 super.removeEdge(i); 084 } 085 086 // *** Callbacks *** 087 088 @Override 089 protected boolean addEdgeCallback(AbstractEdge edge) { 090 AbstractNode opposite = edge.getOpposite(this); 091 TwoEdges ee = neighborMap.get(opposite); 092 if (ee == null) 093 ee = new TwoEdges(); 094 char type = edgeType(edge); 095 if (type != O_EDGE) { 096 if (ee.in != null) 097 return false; 098 ee.in = edge; 099 } 100 if (type != I_EDGE) { 101 if (ee.out != null) 102 return false; 103 ee.out = edge; 104 } 105 neighborMap.put(opposite, ee); 106 return super.addEdgeCallback(edge); 107 } 108 109 @Override 110 protected void clearCallback() { 111 neighborMap.clear(); 112 super.clearCallback(); 113 } 114 115 // *** Others *** 116 117 @SuppressWarnings("unchecked") 118 @Override 119 public <T extends Node> Iterator<T> getNeighborNodeIterator() { 120 return (Iterator<T>) Collections.unmodifiableSet(neighborMap.keySet()) 121 .iterator(); 122 } 123}