001    /**
002     * Licensed to the Apache Software Foundation (ASF) under one
003     * or more contributor license agreements.  See the NOTICE file
004     * distributed with this work for additional information
005     * regarding copyright ownership.  The ASF licenses this file
006     * to you under the Apache License, Version 2.0 (the
007     * "License"); you may not use this file except in compliance
008     * with the License.  You may obtain a copy of the License at
009     *
010     *     http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    
019    package org.apache.hadoop.fs.http.server;
020    
021    import org.apache.hadoop.classification.InterfaceAudience;
022    import org.apache.hadoop.lib.service.FileSystemAccess;
023    import org.apache.hadoop.lib.servlet.FileSystemReleaseFilter;
024    
025    /**
026     * Filter that releases FileSystemAccess filesystem instances upon HTTP request
027     * completion.
028     */
029    @InterfaceAudience.Private
030    public class HttpFSReleaseFilter extends FileSystemReleaseFilter {
031    
032      /**
033       * Returns the {@link FileSystemAccess} service to return the FileSystemAccess filesystem
034       * instance to.
035       *
036       * @return the FileSystemAccess service.
037       */
038      @Override
039      protected FileSystemAccess getFileSystemAccess() {
040        return HttpFSServerWebApp.get().get(FileSystemAccess.class);
041      }
042    
043    }