/*
* 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.
*/
package org.apache.lucene.analysis.miscellaneous;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.lucene.analysis.CharArraySet;
import org.apache.lucene.analysis.TokenFilter;
import org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.util.ResourceLoader;
import org.apache.lucene.analysis.util.ResourceLoaderAware;
import org.apache.lucene.analysis.util.TokenFilterFactory;
import static org.apache.lucene.analysis.miscellaneous.WordDelimiterGraphFilter.*;
import static org.apache.lucene.analysis.miscellaneous.WordDelimiterIterator.*;
/**
* Factory for {@link WordDelimiterGraphFilter}.
* <pre class="prettyprint">
* <fieldType name="text_wd" class="solr.TextField" positionIncrementGap="100">
* <analyzer>
* <tokenizer class="solr.WhitespaceTokenizerFactory"/>
* <filter class="solr.WordDelimiterGraphFilterFactory" protected="protectedword.txt"
* preserveOriginal="0" splitOnNumerics="1" splitOnCaseChange="1"
* catenateWords="0" catenateNumbers="0" catenateAll="0"
* generateWordParts="1" generateNumberParts="1" stemEnglishPossessive="1"
* types="wdfftypes.txt" />
* </analyzer>
* </fieldType></pre>
*/
public class WordDelimiterGraphFilterFactory extends TokenFilterFactory implements ResourceLoaderAware {
public static final String PROTECTED_TOKENS = "protected";
public static final String TYPES = "types";
private final String wordFiles;
private final String types;
private final int flags;
byte[] typeTable = null;
private CharArraySet protectedWords = null;
/** Creates a new WordDelimiterGraphFilterFactory */
public WordDelimiterGraphFilterFactory(Map<String, String> args) {
super(args);
int flags = 0;
if (getInt(args, "generateWordParts", 1) != 0) {
flags |= GENERATE_WORD_PARTS;
}
if (getInt(args, "generateNumberParts", 1) != 0) {
flags |= GENERATE_NUMBER_PARTS;
}
if (getInt(args, "catenateWords", 0) != 0) {
flags |= CATENATE_WORDS;
}
if (getInt(args, "catenateNumbers", 0) != 0) {
flags |= CATENATE_NUMBERS;
}
if (getInt(args, "catenateAll", 0) != 0) {
flags |= CATENATE_ALL;
}
if (getInt(args, "splitOnCaseChange", 1) != 0) {
flags |= SPLIT_ON_CASE_CHANGE;
}
if (getInt(args, "splitOnNumerics", 1) != 0) {
flags |= SPLIT_ON_NUMERICS;
}
if (getInt(args, "preserveOriginal", 0) != 0) {
flags |= PRESERVE_ORIGINAL;
}
if (getInt(args, "stemEnglishPossessive", 1) != 0) {
flags |= STEM_ENGLISH_POSSESSIVE;
}
wordFiles = get(args, PROTECTED_TOKENS);
types = get(args, TYPES);
this.flags = flags;
if (!args.isEmpty()) {
throw new IllegalArgumentException("Unknown parameters: " + args);
}
}
@Override
public void inform(ResourceLoader loader) throws IOException {
if (wordFiles != null) {
protectedWords = getWordSet(loader, wordFiles, false);
}
if (types != null) {
List<String> files = splitFileNames( types );
List<String> wlist = new ArrayList<>();
for( String file : files ){
List<String> lines = getLines(loader, file.trim());
wlist.addAll( lines );
}
typeTable = parseTypes(wlist);
}
}
@Override
public TokenFilter create(TokenStream input) {
return new WordDelimiterGraphFilter(input, typeTable == null ? WordDelimiterIterator.DEFAULT_WORD_DELIM_TABLE : typeTable,
flags, protectedWords);
}
// source => type
private static Pattern typePattern = Pattern.compile( "(.*)\\s*=>\\s*(.*)\\s*$" );
// parses a list of MappingCharFilter style rules into a custom byte[] type table
private byte[] parseTypes(List<String> rules) {
SortedMap<Character,Byte> typeMap = new TreeMap<>();
for( String rule : rules ){
Matcher m = typePattern.matcher(rule);
if( !m.find() )
throw new IllegalArgumentException("Invalid Mapping Rule : [" + rule + "]");
String lhs = parseString(m.group(1).trim());
Byte rhs = parseType(m.group(2).trim());
if (lhs.length() != 1)
throw new IllegalArgumentException("Invalid Mapping Rule : [" + rule + "]. Only a single character is allowed.");
if (rhs == null)
throw new IllegalArgumentException("Invalid Mapping Rule : [" + rule + "]. Illegal type.");
typeMap.put(lhs.charAt(0), rhs);
}
// ensure the table is always at least as big as DEFAULT_WORD_DELIM_TABLE for performance
byte types[] = new byte[Math.max(typeMap.lastKey()+1, WordDelimiterIterator.DEFAULT_WORD_DELIM_TABLE.length)];
for (int i = 0; i < types.length; i++)
types[i] = WordDelimiterIterator.getType(i);
for (Map.Entry<Character,Byte> mapping : typeMap.entrySet())
types[mapping.getKey()] = mapping.getValue();
return types;
}
private Byte parseType(String s) {
if (s.equals("LOWER"))
return LOWER;
else if (s.equals("UPPER"))
return UPPER;
else if (s.equals("ALPHA"))
return ALPHA;
else if (s.equals("DIGIT"))
return DIGIT;
else if (s.equals("ALPHANUM"))
return ALPHANUM;
else if (s.equals("SUBWORD_DELIM"))
return SUBWORD_DELIM;
else
return null;
}
char[] out = new char[256];
private 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 '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 );
}
}