| /** |
| * 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. |
| */ |
| |
| package org.apache.hadoop.fs.s3; |
| |
| import java.io.ByteArrayInputStream; |
| import java.io.ByteArrayOutputStream; |
| import java.io.DataInputStream; |
| import java.io.DataOutputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| |
| /** |
| * Holds file metadata including type (regular file, or directory), |
| * and the list of blocks that are pointers to the data. |
| */ |
| @InterfaceAudience.Private |
| @InterfaceStability.Unstable |
| public class INode { |
| |
| enum FileType { |
| DIRECTORY, FILE |
| } |
| |
| public static final FileType[] FILE_TYPES = { |
| FileType.DIRECTORY, |
| FileType.FILE |
| }; |
| |
| public static final INode DIRECTORY_INODE = new INode(FileType.DIRECTORY, null); |
| |
| private FileType fileType; |
| private Block[] blocks; |
| |
| public INode(FileType fileType, Block[] blocks) { |
| this.fileType = fileType; |
| if (isDirectory() && blocks != null) { |
| throw new IllegalArgumentException("A directory cannot contain blocks."); |
| } |
| this.blocks = blocks; |
| } |
| |
| public Block[] getBlocks() { |
| return blocks; |
| } |
| |
| public FileType getFileType() { |
| return fileType; |
| } |
| |
| public boolean isDirectory() { |
| return fileType == FileType.DIRECTORY; |
| } |
| |
| public boolean isFile() { |
| return fileType == FileType.FILE; |
| } |
| |
| public long getSerializedLength() { |
| return 1L + (blocks == null ? 0 : 4 + blocks.length * 16); |
| } |
| |
| |
| public InputStream serialize() throws IOException { |
| ByteArrayOutputStream bytes = new ByteArrayOutputStream(); |
| DataOutputStream out = new DataOutputStream(bytes); |
| out.writeByte(fileType.ordinal()); |
| if (isFile()) { |
| out.writeInt(blocks.length); |
| for (int i = 0; i < blocks.length; i++) { |
| out.writeLong(blocks[i].getId()); |
| out.writeLong(blocks[i].getLength()); |
| } |
| } |
| out.close(); |
| return new ByteArrayInputStream(bytes.toByteArray()); |
| } |
| |
| public static INode deserialize(InputStream in) throws IOException { |
| if (in == null) { |
| return null; |
| } |
| DataInputStream dataIn = new DataInputStream(in); |
| FileType fileType = INode.FILE_TYPES[dataIn.readByte()]; |
| switch (fileType) { |
| case DIRECTORY: |
| in.close(); |
| return INode.DIRECTORY_INODE; |
| case FILE: |
| int numBlocks = dataIn.readInt(); |
| Block[] blocks = new Block[numBlocks]; |
| for (int i = 0; i < numBlocks; i++) { |
| long id = dataIn.readLong(); |
| long length = dataIn.readLong(); |
| blocks[i] = new Block(id, length); |
| } |
| in.close(); |
| return new INode(fileType, blocks); |
| default: |
| throw new IllegalArgumentException("Cannot deserialize inode."); |
| } |
| } |
| |
| } |