content: package org.apache.solr.analysis;
  
  /*
   * 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.miscellaneous.ASCIIFoldingFilter;
  import org.apache.lucene.analysis.AbstractAnalysisFactory;
  import org.apache.lucene.analysis.TokenFilterFactory;
  
  import java.util.Map;
  
  /**
   * A wrapper for the {@link ASCIIFoldingFilter}. It retains the original token and returns the
   * ASCII folded variant.
   * <p>
   * It is little bit crazy, because we have to wrap the ASCII filter with two other filters
   * in order to get to the original value.
   */
  public class ASCIIDuplicatingFilterFactory extends TokenFilterFactory {
      public ASCIIDuplicatingFilterFactory(Map<String, String> args) {
          super(args);
          if (!args.isEmpty()) {
              throw new IllegalArgumentException("Unknown parameter(s): " + args);
          }
      }
  
      public OnChangeDuplicatingFilter create(TokenStream input) {
          return new OnChangeDuplicatingFilter(new ASCIIFoldingFilter(new DuplicatingFilter(input)));
      }
  
      public AbstractAnalysisFactory getMultiTermComponent() {
          return this;
      }
  }
  
  