| /** |
| * 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.raid; |
| |
| import java.io.InputStream; |
| import java.io.IOException; |
| import java.io.UnsupportedEncodingException; |
| import java.net.URLDecoder; |
| import java.util.List; |
| import java.util.LinkedList; |
| |
| import org.apache.hadoop.util.LineReader; |
| import org.apache.hadoop.io.Text; |
| |
| /** |
| * Represents the contents of a HAR Index file. The HAR is assumed to be |
| * comprising of RAID parity files only and no directories. |
| */ |
| public class HarIndex { |
| public static final String indexFileName = "_index"; |
| private List<IndexEntry> entries = new LinkedList<IndexEntry>(); |
| |
| /** |
| * Represents information in a single line of the HAR index file. |
| */ |
| public static class IndexEntry { |
| String fileName; // Name of the file in the part file. |
| long startOffset; // Start offset within the part file. |
| long length; // Length of this file within the part file. |
| long mtime; // Modification time of the file. |
| String partFileName; // Name of the part file. |
| |
| IndexEntry(String fileName, long startOffset, long length, |
| long mtime, String partFileName) { |
| this.fileName = fileName; |
| this.startOffset = startOffset; |
| this.length = length; |
| this.mtime = mtime; |
| this.partFileName = partFileName; |
| } |
| |
| public String toString() { |
| return "fileName=" + fileName + |
| ", startOffset=" + startOffset + |
| ", length=" + length + |
| ", mtime=" + mtime + |
| ", partFileName=" + partFileName; |
| } |
| } |
| |
| /** |
| * Constructor that reads the contents of the index file. |
| * @param in An input stream to the index file. |
| * @param max The size of the index file. |
| * @throws IOException |
| */ |
| public HarIndex(InputStream in, long max) throws IOException { |
| LineReader lineReader = new LineReader(in); |
| Text text = new Text(); |
| long nread = 0; |
| while (nread < max) { |
| int n = lineReader.readLine(text); |
| nread += n; |
| String line = text.toString(); |
| try { |
| parseLine(line); |
| } catch (UnsupportedEncodingException e) { |
| throw new IOException("UnsupportedEncodingException after reading " + |
| nread + "bytes"); |
| } |
| } |
| } |
| |
| /** |
| * Parses each line and extracts relevant information. |
| * @param line |
| * @throws UnsupportedEncodingException |
| */ |
| void parseLine(String line) throws UnsupportedEncodingException { |
| String[] splits = line.split(" "); |
| |
| boolean isDir = "dir".equals(splits[1]) ? true: false; |
| if (!isDir && splits.length >= 6) { |
| String name = URLDecoder.decode(splits[0], "UTF-8"); |
| String partName = URLDecoder.decode(splits[2], "UTF-8"); |
| long startIndex = Long.parseLong(splits[3]); |
| long length = Long.parseLong(splits[4]); |
| String[] newsplits = URLDecoder.decode(splits[5],"UTF-8").split(" "); |
| if (newsplits != null && newsplits.length >= 4) { |
| long mtime = Long.parseLong(newsplits[0]); |
| IndexEntry entry = new IndexEntry( |
| name, startIndex, length, mtime, partName); |
| entries.add(entry); |
| } |
| } |
| } |
| |
| /** |
| * Finds the index entry corresponding to a HAR partFile at an offset. |
| * @param partName The name of the part file (part-*). |
| * @param partFileOffset The offset into the part file. |
| * @return The entry corresponding to partName:partFileOffset. |
| */ |
| public IndexEntry findEntry(String partName, long partFileOffset) { |
| for (IndexEntry e: entries) { |
| boolean nameMatch = partName.equals(e.partFileName); |
| boolean inRange = (partFileOffset >= e.startOffset) && |
| (partFileOffset < e.startOffset + e.length); |
| if (nameMatch && inRange) { |
| return e; |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * Finds the index entry corresponding to a file in the archive |
| */ |
| public IndexEntry findEntryByFileName(String fileName) { |
| for (IndexEntry e: entries) { |
| if (fileName.equals(e.fileName)) { |
| return e; |
| } |
| } |
| return null; |
| } |
| |
| } |