package org.apache.lucene.analysis.miscellaneous;
/*
* 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 org.apache.lucene.analysis.TokenStream;
import org.apache.lucene.analysis.util.CharArraySet;
import org.apache.lucene.analysis.util.TokenFilterFactory;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Map;
import java.util.Set;
/**
* Factory for {@link CapitalizationFilter}.
* <p/>
* The factory takes parameters:<br/>
* "onlyFirstWord" - should each word be capitalized or all of the words?<br/>
* "keep" - a keep word list. Each word that should be kept separated by whitespace.<br/>
* "keepIgnoreCase - true or false. If true, the keep list will be considered case-insensitive.<br/>
* "forceFirstLetter" - Force the first letter to be capitalized even if it is in the keep list<br/>
* "okPrefix" - do not change word capitalization if a word begins with something in this list.
* for example if "McK" is on the okPrefix list, the word "McKinley" should not be changed to
* "Mckinley"<br/>
* "minWordLength" - how long the word needs to be to get capitalization applied. If the
* minWordLength is 3, "and" > "And" but "or" stays "or"<br/>
* "maxWordCount" - if the token contains more then maxWordCount words, the capitalization is
* assumed to be correct.<br/>
*
* <pre class="prettyprint">
* <fieldType name="text_cptlztn" class="solr.TextField" positionIncrementGap="100">
* <analyzer>
* <tokenizer class="solr.WhitespaceTokenizerFactory"/>
* <filter class="solr.CapitalizationFilterFactory" onlyFirstWord="true"
* keep="java solr lucene" keepIgnoreCase="false"
* okPrefix="McK McD McA"/>
* </analyzer>
* </fieldType></pre>
*
* @since solr 1.3
*/
public class CapitalizationFilterFactory extends TokenFilterFactory {
public static final String KEEP = "keep";
public static final String KEEP_IGNORE_CASE = "keepIgnoreCase";
public static final String OK_PREFIX = "okPrefix";
public static final String MIN_WORD_LENGTH = "minWordLength";
public static final String MAX_WORD_COUNT = "maxWordCount";
public static final String MAX_TOKEN_LENGTH = "maxTokenLength";
public static final String ONLY_FIRST_WORD = "onlyFirstWord";
public static final String FORCE_FIRST_LETTER = "forceFirstLetter";
CharArraySet keep;
Collection<char[]> okPrefix = Collections.emptyList(); // for Example: McK
final int minWordLength; // don't modify capitalization for words shorter then this
final int maxWordCount;
final int maxTokenLength;
final boolean onlyFirstWord;
final boolean forceFirstLetter; // make sure the first letter is capital even if it is in the keep list
/** Creates a new CapitalizationFilterFactory */
public CapitalizationFilterFactory(Map<String, String> args) {
super(args);
assureMatchVersion();
boolean ignoreCase = getBoolean(args, KEEP_IGNORE_CASE, false);
Set<String> k = getSet(args, KEEP);
if (k != null) {
keep = new CharArraySet(luceneMatchVersion, 10, ignoreCase);
keep.addAll(k);
}
k = getSet(args, OK_PREFIX);
if (k != null) {
okPrefix = new ArrayList<char[]>();
for (String item : k) {
okPrefix.add(item.toCharArray());
}
}
minWordLength = getInt(args, MIN_WORD_LENGTH, 0);
maxWordCount = getInt(args, MAX_WORD_COUNT, CapitalizationFilter.DEFAULT_MAX_WORD_COUNT);
maxTokenLength = getInt(args, MAX_TOKEN_LENGTH, CapitalizationFilter.DEFAULT_MAX_TOKEN_LENGTH);
onlyFirstWord = getBoolean(args, ONLY_FIRST_WORD, true);
forceFirstLetter = getBoolean(args, FORCE_FIRST_LETTER, true);
if (!args.isEmpty()) {
throw new IllegalArgumentException("Unknown parameters: " + args);
}
}
@Override
public CapitalizationFilter create(TokenStream input) {
return new CapitalizationFilter(input, onlyFirstWord, keep,
forceFirstLetter, okPrefix, minWordLength, maxWordCount, maxTokenLength);
}
}