package org.apache.lucene.analysis.charfilter;
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import java.io.File;
import java.io.IOException;
import java.io.Reader;
import java.util.ArrayList;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.lucene.analysis.charfilter.MappingCharFilter;
import org.apache.lucene.analysis.charfilter.NormalizeCharMap;
import org.apache.lucene.analysis.util.*;
/**
* Factory for {@link MappingCharFilter}.
* <pre class="prettyprint" >
* <fieldType name="text_map" class="solr.TextField" positionIncrementGap="100">
* <analyzer>
* <charFilter class="solr.MappingCharFilterFactory" mapping="mapping.txt"/>
* <tokenizer class="solr.WhitespaceTokenizerFactory"/>
* </analyzer>
* </fieldType></pre>
*
*
* @since Solr 1.4
*
*/
public class MappingCharFilterFactory extends CharFilterFactory implements
ResourceLoaderAware, MultiTermAwareComponent {
protected NormalizeCharMap normMap;
private String mapping;
// TODO: this should use inputstreams from the loader, not File!
@Override
public void inform(ResourceLoader loader) throws IOException {
mapping = args.get("mapping");
if (mapping != null) {
List<String> wlist = null;
File mappingFile = new File(mapping);
if (mappingFile.exists()) {
wlist = getLines(loader, mapping);
} else {
List<String> files = splitFileNames(mapping);
wlist = new ArrayList<String>();
for (String file : files) {
List<String> lines = getLines(loader, file.trim());
wlist.addAll(lines);
}
}
final NormalizeCharMap.Builder builder = new NormalizeCharMap.Builder();
parseRules(wlist, builder);
normMap = builder.build();
if (normMap.map == null) {
// if the inner FST is null, it means it accepts nothing (e.g. the file is empty)
// so just set the whole map to null
normMap = null;
}
}
}
@Override
public Reader create(Reader input) {
// if the map is null, it means there's actually no mappings... just return the original stream
// as there is nothing to do here.
return normMap == null ? input : new MappingCharFilter(normMap,input);
}
// "source" => "target"
static Pattern p = Pattern.compile( "\"(.*)\"\\s*=>\\s*\"(.*)\"\\s*$" );
protected void parseRules( List<String> rules, NormalizeCharMap.Builder builder ){
for( String rule : rules ){
Matcher m = p.matcher( rule );
if( !m.find() )
throw new IllegalArgumentException("Invalid Mapping Rule : [" + rule + "], file = " + mapping);
builder.add( parseString( m.group( 1 ) ), parseString( m.group( 2 ) ) );
}
}
char[] out = new char[256];
protected String parseString( String s ){
int readPos = 0;
int len = s.length();
int writePos = 0;
while( readPos < len ){
char c = s.charAt( readPos++ );
if( c == '\\' ){
if( readPos >= len )
throw new IllegalArgumentException("Invalid escaped char in [" + s + "]");
c = s.charAt( readPos++ );
switch( c ) {
case '\\' : c = '\\'; break;
case '"' : c = '"'; break;
case 'n' : c = '\n'; break;
case 't' : c = '\t'; break;
case 'r' : c = '\r'; break;
case 'b' : c = '\b'; break;
case 'f' : c = '\f'; break;
case 'u' :
if( readPos + 3 >= len )
throw new IllegalArgumentException("Invalid escaped char in [" + s + "]");
c = (char)Integer.parseInt( s.substring( readPos, readPos + 4 ), 16 );
readPos += 4;
break;
}
}
out[writePos++] = c;
}
return new String( out, 0, writePos );
}
@Override
public AbstractAnalysisFactory getMultiTermComponent() {
return this;
}
}