001package net.sf.logdistiller.xml; 002 003/* 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017import java.io.InputStream; 018import java.util.HashSet; 019import java.util.Set; 020import org.xml.sax.EntityResolver; 021import org.xml.sax.InputSource; 022 023public class LogDistillerEntityResolver 024 implements EntityResolver 025{ 026 public final static String LATEST_DTD = "logdistiller-1_4.dtd"; 027 028 public final static String LATEST_DTD_URL = "http://logdistiller.sourceforge.net/dtd/" + LATEST_DTD; 029 030 private final static Set<String> DTDS = new HashSet<String>() 031 { 032 private static final long serialVersionUID = -7218559731707450072L; 033 034 { 035 add( "logdistiller-1_0.dtd" ); 036 add( "logdistiller-1_1.dtd" ); 037 add( "logdistiller-1_2.dtd" ); 038 add( "logdistiller-1_3.dtd" ); 039 add( "logdistiller-1_4.dtd" ); 040 } 041 }; 042 043 private final static int LEN = 20; // length of dtd string... 044 045 private String currentDtd; 046 047 public InputSource resolveEntity( String publicId, String systemId ) 048 { 049 if ( systemId.length() < LEN ) 050 { 051 return null; 052 } 053 String dtd = systemId.substring( systemId.length() - LEN ); 054 if ( DTDS.contains( dtd ) ) 055 { 056 currentDtd = dtd; 057 InputStream in = LogDistillerEntityResolver.class.getResourceAsStream( dtd ); 058 if ( in == null ) 059 { 060 throw new RuntimeException( "unable to load DTD " + dtd ); 061 } 062 else 063 { 064 return new InputSource( in ); 065 } 066 } 067 else 068 { 069 return null; 070 } 071 } 072 073 public String getCurrentDtd() 074 { 075 return currentDtd; 076 } 077}