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    package org.apache.hadoop.hdfs.server.namenode;
019    
020    import org.apache.hadoop.classification.InterfaceAudience;
021    import org.apache.hadoop.fs.permission.PermissionStatus;
022    import org.apache.hadoop.hdfs.server.namenode.INodeFile.HeaderFormat;
023    
024    /**
025     * The attributes of a file.
026     */
027    @InterfaceAudience.Private
028    public interface INodeFileAttributes extends INodeAttributes {
029      /** @return the file replication. */
030      public short getFileReplication();
031    
032      /** @return preferred block size in bytes */
033      public long getPreferredBlockSize();
034      
035      /** @return the header as a long. */
036      public long getHeaderLong();
037    
038      /** A copy of the inode file attributes */
039      public static class SnapshotCopy extends INodeAttributes.SnapshotCopy
040          implements INodeFileAttributes {
041        private final long header;
042    
043        public SnapshotCopy(byte[] name, PermissionStatus permissions,
044            long modificationTime, long accessTime,
045            short replication, long preferredBlockSize) {
046          super(name, permissions, modificationTime, accessTime);
047    
048          final long h = HeaderFormat.combineReplication(0L, replication);
049          header = HeaderFormat.combinePreferredBlockSize(h, preferredBlockSize);
050        }
051    
052        public SnapshotCopy(INodeFile file) {
053          super(file);
054          this.header = file.getHeaderLong();
055        }
056    
057        @Override
058        public short getFileReplication() {
059          return HeaderFormat.getReplication(header);
060        }
061    
062        @Override
063        public long getPreferredBlockSize() {
064          return HeaderFormat.getPreferredBlockSize(header);
065        }
066    
067        @Override
068        public long getHeaderLong() {
069          return header;
070        }
071      }
072    }