| /* |
| * 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.pattern; |
| |
| import java.util.Map; |
| import org.apache.lucene.analysis.TokenizerFactory; |
| import org.apache.lucene.util.AttributeFactory; |
| import org.apache.lucene.util.automaton.Automaton; |
| import org.apache.lucene.util.automaton.Operations; |
| import org.apache.lucene.util.automaton.RegExp; |
| |
| /** |
| * Factory for {@link SimplePatternSplitTokenizer}, for producing tokens by splitting according to |
| * the provided regexp. |
| * |
| * <p>This tokenizer uses Lucene {@link RegExp} pattern matching to construct distinct tokens for |
| * the input stream. The syntax is more limited than {@link PatternTokenizer}, but the tokenization |
| * is quite a bit faster. It takes two arguments: <br> |
| * |
| * <ul> |
| * <li>"pattern" (required) is the regular expression, according to the syntax described at {@link |
| * RegExp} |
| * <li>"maxDeterminizedStates" (optional, default 10000) the limit on total state count for the |
| * determined automaton computed from the regexp |
| * </ul> |
| * |
| * <p>The pattern matches the characters that should split tokens, like {@code String.split}, and |
| * the matching is greedy such that the longest token separator matching at a given point is |
| * matched. Empty tokens are never created. |
| * |
| * <p>For example, to match tokens delimited by simple whitespace characters: |
| * |
| * <pre class="prettyprint"> |
| * <fieldType name="text_ptn" class="solr.TextField" positionIncrementGap="100"> |
| * <analyzer> |
| * <tokenizer class="solr.SimplePatternSplitTokenizerFactory" pattern="[ \t\r\n]+"/> |
| * </analyzer> |
| * </fieldType></pre> |
| * |
| * @lucene.experimental |
| * @see SimplePatternSplitTokenizer |
| * @since 6.5.0 |
| * @lucene.spi {@value #NAME} |
| */ |
| public class SimplePatternSplitTokenizerFactory extends TokenizerFactory { |
| |
| /** SPI name */ |
| public static final String NAME = "simplePatternSplit"; |
| |
| public static final String PATTERN = "pattern"; |
| private final Automaton dfa; |
| private final int maxDeterminizedStates; |
| |
| /** Creates a new SimpleSplitPatternTokenizerFactory */ |
| public SimplePatternSplitTokenizerFactory(Map<String, String> args) { |
| super(args); |
| maxDeterminizedStates = |
| getInt(args, "maxDeterminizedStates", Operations.DEFAULT_MAX_DETERMINIZED_STATES); |
| dfa = |
| Operations.determinize( |
| new RegExp(require(args, PATTERN)).toAutomaton(), maxDeterminizedStates); |
| if (args.isEmpty() == false) { |
| throw new IllegalArgumentException("Unknown parameters: " + args); |
| } |
| } |
| |
| /** Default ctor for compatibility with SPI */ |
| public SimplePatternSplitTokenizerFactory() { |
| throw defaultCtorException(); |
| } |
| |
| @Override |
| public SimplePatternSplitTokenizer create(final AttributeFactory factory) { |
| return new SimplePatternSplitTokenizer(factory, dfa); |
| } |
| } |