content: package org.apache.lucene.index;
  
  /**
   * 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.store.Directory;
  
  import java.io.IOException;
  import java.util.Map;
  import java.util.Collection;
  
  class ReadOnlyDirectoryReader extends DirectoryReader {
    ReadOnlyDirectoryReader(Directory directory, SegmentInfos sis, IndexDeletionPolicy deletionPolicy, int termInfosIndexDivisor,
                            Collection<ReaderFinishedListener> readerFinishedListeners) throws IOException {
      super(directory, sis, deletionPolicy, true, termInfosIndexDivisor, readerFinishedListeners);
    }
  
    ReadOnlyDirectoryReader(Directory directory, SegmentInfos infos, SegmentReader[] oldReaders, int[] oldStarts,  Map<String,byte[]> oldNormsCache, boolean doClone,
                            int termInfosIndexDivisor, Collection<ReaderFinishedListener> readerFinishedListeners) throws IOException {
      super(directory, infos, oldReaders, oldStarts, oldNormsCache, true, doClone, termInfosIndexDivisor, readerFinishedListeners);
    }
    
    ReadOnlyDirectoryReader(IndexWriter writer, SegmentInfos infos, int termInfosIndexDivisor, boolean applyAllDeletes) throws IOException {
      super(writer, infos, termInfosIndexDivisor, applyAllDeletes);
    }
    
    @Override
    protected void acquireWriteLock() {
      ReadOnlySegmentReader.noWrite();
    }
  }
  