001/* 002 * BioJava development code 003 * 004 * This code may be freely distributed and modified under the 005 * terms of the GNU Lesser General Public Licence. This should 006 * be distributed with the code. If you do not have a copy, 007 * see: 008 * 009 * http://www.gnu.org/copyleft/lesser.html 010 * 011 * Copyright for this code is held jointly by the individual 012 * authors. These should be listed in @author doc comments. 013 * 014 * For more information on the BioJava project and its aims, 015 * or to join the biojava-l mailing list, visit the home page 016 * at: 017 * 018 * http://www.biojava.org/ 019 * 020 */ 021 022package org.biojava.bio.program.tagvalue; 023 024import java.util.Map; 025import java.util.Set; 026 027import org.biojava.utils.ParserException; 028import org.biojava.utils.SmallMap; 029 030/** 031 * <p> 032 * Pushes a new parser and listener, or delegate to a listener depending on the 033 * tag. 034 * </p> 035 * 036 * <p> 037 * setParserListener() is used to associate a tag with a TagValueParser and 038 * TagValueListener. When this tag is encountered, the pair will be pushed onto 039 * the parser processing stack and will gain control of the stream until that 040 * tag has ended. setListener() is used to associate a listener with a tag that 041 * will be used to handle those values without pushing a sub-context. 042 * The delegator is constructed with a default TagValueListener that will be 043 * informed of all events for which there are no explicit delegate pairs 044 * registered. 045 * </p> 046 * 047 * @author Matthew Pocock 048 * @since 1.2 049 */ 050public class TagDelegator 051 extends 052 SimpleTagValueWrapper 053{ 054 private Map parsers; 055 private Map listeners; 056 private TagValueParser delegateParser; 057 058 private TagValueParser parser; 059 private TagValueListener listener; 060 061 { 062 parsers = new SmallMap(); 063 listeners = new SmallMap(); 064 } 065 066 public TagDelegator() { 067 super(); 068 } 069 070 public TagDelegator(TagValueListener delegate) { 071 super(delegate); 072 parsers = new SmallMap(); 073 listeners = new SmallMap(); 074 } 075 076 public void setDelegateParser(TagValueParser delegateParser) { 077 this.delegateParser = delegateParser; 078 } 079 080 public TagValueParser getDelegateParser() { 081 return delegateParser; 082 } 083 084 public void startTag(Object tag) 085 throws ParserException { 086 parser = (TagValueParser) parsers.get(tag); 087 listener = (TagValueListener) listeners.get(tag); 088 089 if(parser == null && listener != null) { 090 listener.startTag(tag); 091 } else { 092 super.startTag(tag); 093 } 094 } 095 096 public void endTag() 097 throws ParserException { 098 if(parser == null && listener != null) { 099 listener.endTag(); 100 } else { 101 super.endTag(); 102 } 103 } 104 105 public void value(TagValueContext tvc, Object value) 106 throws ParserException { 107 if(parser != null) { 108 tvc.pushParser(parser, listener); 109 } else if(listener != null) { 110 listener.value(tvc, value); 111 } else if(delegateParser != null) { 112 tvc.pushParser(delegateParser, getDelegate()); 113 } else { 114 super.value(tvc, value); 115 } 116 } 117 118 public void setParserListener( 119 Object tag, 120 TagValueParser parser, 121 TagValueListener listener 122 ) { 123 parsers.put(tag, parser); 124 listeners.put(tag, listener); 125 } 126 127 public void setListener( 128 Object tag, 129 TagValueListener listener 130 ) { 131 listeners.put(tag, listener); 132 } 133 134 public TagValueParser getParser(Object tag) { 135 return (TagValueParser) parsers.get(tag); 136 } 137 138 public TagValueListener getListener(Object tag) { 139 return (TagValueListener) listeners.get(tag); 140 } 141 142 public Set getTags() { 143 return listeners.keySet(); 144 } 145}