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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>A few changes has been made to the static Snowball code and compiled stemmers:
*
* <ul>
* <li>Class SnowballProgram is made abstract and contains new abstract method stem() to avoid
* reflection in Lucene filter class SnowballFilter.
* <li>All use of StringBuffers has been refactored to StringBuilder for speed.
* <li>Snowball BSD license header has been added to the Java classes to avoid having RAT adding
* ASL headers.
* </ul>
*
* <p>See the Snowball <a href ="http://snowball.tartarus.org/">home page</a> for more information
* about the algorithms.
*
* <p><b>IMPORTANT NOTICE ON BACKWARDS COMPATIBILITY!</b>
*
* <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>For more information about this issue see: https://issues.apache.org/jira/browse/LUCENE-1142
*/
package org.apache.lucene.analysis.snowball;