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.stream.file; 033 034import java.io.BufferedReader; 035import java.io.FileInputStream; 036import java.io.IOException; 037import java.io.InputStream; 038import java.io.InputStreamReader; 039import java.io.Reader; 040import java.util.zip.GZIPInputStream; 041 042import org.graphstream.stream.file.dgs.DGSParser; 043import org.graphstream.util.parser.ParseException; 044import org.graphstream.util.parser.Parser; 045import org.graphstream.util.parser.ParserFactory; 046 047/** 048 * Class responsible for parsing files in the DGS format. 049 * 050 * <p> 051 * The DGS file format is especially designed for storing dynamic graph 052 * definitions into a file. More information about the DGS file format will be 053 * found on the GraphStream web site: <a 054 * href="http://graphstream-project.org/">http://graphstream-project.org/</a> 055 * </p> 056 * 057 * The usual file name extension used for this format is ".dgs". 058 * 059 * @see FileSource 060 */ 061public class FileSourceDGS extends FileSourceParser { 062 /* 063 * (non-Javadoc) 064 * 065 * @see org.graphstream.stream.file.FileSourceParser#getNewParserFactory() 066 */ 067 public ParserFactory getNewParserFactory() { 068 return new ParserFactory() { 069 public Parser newParser(Reader reader) { 070 return new DGSParser(FileSourceDGS.this, reader); 071 } 072 }; 073 } 074 075 @Override 076 public boolean nextStep() throws IOException { 077 try { 078 return ((DGSParser) parser).nextStep(); 079 } catch (ParseException e) { 080 throw new IOException(e); 081 } 082 } 083 084 @Override 085 protected Reader createReaderForFile(String filename) throws IOException { 086 InputStream is = null; 087 088 is = new FileInputStream(filename); 089 090 if (is.markSupported()) 091 is.mark(128); 092 093 try { 094 is = new GZIPInputStream(is); 095 } catch (IOException e1) { 096 // 097 // This is not a gzip input. 098 // But gzip has eat some bytes so we reset the stream 099 // or close and open it again. 100 // 101 if (is.markSupported()) { 102 try { 103 is.reset(); 104 } catch (IOException e2) { 105 // 106 // Dirty but we hope do not get there 107 // 108 e2.printStackTrace(); 109 } 110 } else { 111 try { 112 is.close(); 113 } catch (IOException e2) { 114 // 115 // Dirty but we hope do not get there 116 // 117 e2.printStackTrace(); 118 } 119 120 is = new FileInputStream(filename); 121 } 122 } 123 124 return new BufferedReader(new InputStreamReader(is)); 125 } 126}