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/*
* 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.
*/
/**
* {@link org.apache.lucene.analysis.TokenFilter} and {@link
* org.apache.lucene.analysis.Analyzer} implementations that use Snowball
* stemmers.
* <p>
* This project provides pre-compiled version of the Snowball stemmers
* based on revision 500 of the Tartarus Snowball repository,
* together with classes integrating them with the Lucene search engine.
* </p>
* <p>
* A few changes has been made to the static Snowball code and compiled stemmers:
* </p>
* <ul>
* <li>Class SnowballProgram is made abstract and contains new abstract method stem() to avoid reflection in Lucene filter class SnowballFilter.</li>
* <li>All use of StringBuffers has been refactored to StringBuilder for speed.</li>
* <li>Snowball BSD license header has been added to the Java classes to avoid having RAT adding ASL headers.</li>
* </ul>
* <p>
* See the Snowball <a href ="http://snowball.tartarus.org/">home page</a> for more information about the algorithms.
* </p>
*
* <p>
* <b>IMPORTANT NOTICE ON BACKWARDS COMPATIBILITY!</b>
* </p>
* <p>
* An index created using the Snowball module in Lucene 2.3.2 and below
* might not be compatible with the Snowball module in Lucene 2.4 or greater.
* </p>
* <p>
* For more information about this issue see:
* https://issues.apache.org/jira/browse/LUCENE-1142
* </p>
*/
package org.apache.lucene.analysis.snowball;