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.ui.layout; 033 034import java.security.AccessControlException; 035 036/** 037 * A factory in charge or creating various layout implementations. 038 * 039 * This class is mainly used to create the default layout for the graph viewer. 040 * You can also use layouts directly on your graphs, but in this case you do not 041 * need this factory. 042 * 043 * This class looks at the "gs.ui.layout" system property to create a layout 044 * class. You can change this property using 045 * <code>System.setProperty("gs.ui.layout", you_layout_class_name)</code>. 046 */ 047public class Layouts { 048 /** 049 * Creates a layout according to the "org.graphstream.ui.layout" system property. 050 * 051 * @return The new layout or the default GraphStream "Spring-Box" layout if 052 * the "gs.ui.layout" system property is either not set or contains 053 * a class that cannot be found. 054 */ 055 public static Layout newLayoutAlgorithm() { 056 String layoutClassName; 057 058 try { 059 layoutClassName = System.getProperty("gs.ui.layout"); 060 061 if (layoutClassName != null) { 062 System.err.printf("\"gs.ui.layout\" is deprecated,"); 063 System.err.printf("use \"org.graphstream.ui.layout\"" 064 + " instead\n"); 065 } else { 066 layoutClassName = System 067 .getProperty("org.graphstream.ui.layout"); 068 } 069 } catch (AccessControlException e) { 070 layoutClassName = null; 071 } 072 073 if (layoutClassName != null) { 074 try { 075 Class<?> c = Class.forName(layoutClassName); 076 Object object = c.newInstance(); 077 078 if (object instanceof Layout) { 079 return (Layout) object; 080 } else { 081 System.err.printf("class '%s' is not a 'GraphRenderer'%n", 082 object); 083 } 084 } catch (ClassNotFoundException e) { 085 e.printStackTrace(); 086 System.err 087 .printf("Cannot create layout, 'GraphRenderer' class not found : " 088 + e.getMessage()); 089 } catch (InstantiationException e) { 090 e.printStackTrace(); 091 System.err.printf("Cannot create layout, class '" 092 + layoutClassName + "' error : " + e.getMessage()); 093 } catch (IllegalAccessException e) { 094 e.printStackTrace(); 095 System.err.printf("Cannot create layout, class '" 096 + layoutClassName + "' illegal access : " 097 + e.getMessage()); 098 } 099 } 100 101 return new org.graphstream.ui.layout.springbox.implementations.SpringBox( 102 false); 103 } 104}