content: package org.apache.solr.core;
  /**
   * 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 org.apache.lucene.store.MMapDirectory;
  import org.apache.solr.common.params.SolrParams;
  import org.apache.solr.common.util.NamedList;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.io.File;
  import java.io.IOException;
  
  
  /**
   *  Directly provide MMapDirectory instead of relying on {@link org.apache.lucene.store.FSDirectory#open}
   *
   * Can set the following parameters:
   * <ul>
   *  <li>unmap -- See {@link org.apache.lucene.store.MMapDirectory#setUseUnmap(boolean)}</li>
   *  <li>maxChunkSize -- The Max chunk size.  See {@link org.apache.lucene.store.MMapDirectory#setMaxChunkSize(int)}</li>
   * </ul>
   *
   **/
  public class MMapDirectoryFactory extends DirectoryFactory {
    private transient static Logger log = LoggerFactory.getLogger(MMapDirectoryFactory.class);
    boolean unmapHack;
    private int maxChunk;
  
    @Override
    public Directory open(String path) throws IOException {
      MMapDirectory mapDirectory = new MMapDirectory(new File(path));
      try {
        mapDirectory.setUseUnmap(unmapHack);
      } catch (Exception e) {
        log.warn("Unmap not supported on this JVM, continuing on without setting unmap", e);
      }
      mapDirectory.setMaxChunkSize(maxChunk);
      return mapDirectory;
    }
  
    @Override
    public void init(NamedList args) {
      SolrParams params = SolrParams.toSolrParams( args );
      maxChunk = params.getInt("maxChunkSize", MMapDirectory.DEFAULT_MAX_BUFF);
      if (maxChunk <= 0){
        throw new IllegalArgumentException("maxChunk must be greater than 0");
      }
      unmapHack = params.getBool("unmap", true);
    }
  }
  