[120] | 1 | /** |
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| 2 | * Licensed to the Apache Software Foundation (ASF) under one |
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| 3 | * or more contributor license agreements. See the NOTICE file |
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| 4 | * distributed with this work for additional information |
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| 5 | * regarding copyright ownership. The ASF licenses this file |
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| 6 | * to you under the Apache License, Version 2.0 (the |
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| 7 | * "License"); you may not use this file except in compliance |
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| 8 | * with the License. You may obtain a copy of the License at |
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| 9 | * |
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| 10 | * http://www.apache.org/licenses/LICENSE-2.0 |
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| 11 | * |
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| 12 | * Unless required by applicable law or agreed to in writing, software |
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| 13 | * distributed under the License is distributed on an "AS IS" BASIS, |
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| 14 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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| 15 | * See the License for the specific language governing permissions and |
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| 16 | * limitations under the License. |
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| 17 | */ |
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| 18 | package org.apache.hadoop.hdfs.server.datanode; |
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| 19 | |
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| 20 | import java.io.IOException; |
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| 21 | import java.io.InputStream; |
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| 22 | import java.io.OutputStream; |
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| 23 | import java.util.Arrays; |
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| 24 | import java.util.HashMap; |
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| 25 | import java.util.Random; |
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| 26 | |
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| 27 | import javax.management.NotCompliantMBeanException; |
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| 28 | import javax.management.ObjectName; |
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| 29 | import javax.management.StandardMBean; |
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| 30 | |
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| 31 | import org.apache.hadoop.conf.Configurable; |
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| 32 | import org.apache.hadoop.conf.Configuration; |
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| 33 | import org.apache.hadoop.hdfs.protocol.Block; |
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| 34 | import org.apache.hadoop.hdfs.protocol.FSConstants; |
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| 35 | import org.apache.hadoop.hdfs.server.datanode.metrics.FSDatasetMBean; |
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| 36 | import org.apache.hadoop.metrics.util.MBeanUtil; |
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| 37 | import org.apache.hadoop.util.DataChecksum; |
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| 38 | import org.apache.hadoop.util.DiskChecker.DiskErrorException; |
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| 39 | |
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| 40 | /** |
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| 41 | * This class implements a simulated FSDataset. |
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| 42 | * |
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| 43 | * Blocks that are created are recorded but their data (plus their CRCs) are |
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| 44 | * discarded. |
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| 45 | * Fixed data is returned when blocks are read; a null CRC meta file is |
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| 46 | * created for such data. |
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| 47 | * |
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| 48 | * This FSDataset does not remember any block information across its |
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| 49 | * restarts; it does however offer an operation to inject blocks |
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| 50 | * (See the TestInectionForSImulatedStorage() |
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| 51 | * for a usage example of injection. |
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| 52 | * |
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| 53 | * Note the synchronization is coarse grained - it is at each method. |
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| 54 | */ |
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| 55 | |
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| 56 | public class SimulatedFSDataset implements FSConstants, FSDatasetInterface, Configurable{ |
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| 57 | |
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| 58 | public static final String CONFIG_PROPERTY_SIMULATED = |
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| 59 | "dfs.datanode.simulateddatastorage"; |
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| 60 | public static final String CONFIG_PROPERTY_CAPACITY = |
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| 61 | "dfs.datanode.simulateddatastorage.capacity"; |
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| 62 | |
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| 63 | public static final long DEFAULT_CAPACITY = 2L<<40; // 1 terabyte |
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| 64 | public static final byte DEFAULT_DATABYTE = 9; // 1 terabyte |
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| 65 | byte simulatedDataByte = DEFAULT_DATABYTE; |
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| 66 | Configuration conf = null; |
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| 67 | |
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| 68 | static byte[] nullCrcFileData; |
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| 69 | { |
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| 70 | DataChecksum checksum = DataChecksum.newDataChecksum( DataChecksum. |
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| 71 | CHECKSUM_NULL, 16*1024 ); |
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| 72 | byte[] nullCrcHeader = checksum.getHeader(); |
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| 73 | nullCrcFileData = new byte[2 + nullCrcHeader.length]; |
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| 74 | nullCrcFileData[0] = (byte) ((FSDataset.METADATA_VERSION >>> 8) & 0xff); |
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| 75 | nullCrcFileData[1] = (byte) (FSDataset.METADATA_VERSION & 0xff); |
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| 76 | for (int i = 0; i < nullCrcHeader.length; i++) { |
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| 77 | nullCrcFileData[i+2] = nullCrcHeader[i]; |
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| 78 | } |
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| 79 | } |
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| 80 | |
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| 81 | private class BInfo { // information about a single block |
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| 82 | Block theBlock; |
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| 83 | private boolean finalized = false; // if not finalized => ongoing creation |
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| 84 | SimulatedOutputStream oStream = null; |
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| 85 | BInfo(Block b, boolean forWriting) throws IOException { |
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| 86 | theBlock = new Block(b); |
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| 87 | if (theBlock.getNumBytes() < 0) { |
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| 88 | theBlock.setNumBytes(0); |
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| 89 | } |
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| 90 | if (!storage.alloc(theBlock.getNumBytes())) { // expected length - actual length may |
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| 91 | // be more - we find out at finalize |
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| 92 | DataNode.LOG.warn("Lack of free storage on a block alloc"); |
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| 93 | throw new IOException("Creating block, no free space available"); |
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| 94 | } |
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| 95 | |
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| 96 | if (forWriting) { |
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| 97 | finalized = false; |
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| 98 | oStream = new SimulatedOutputStream(); |
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| 99 | } else { |
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| 100 | finalized = true; |
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| 101 | oStream = null; |
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| 102 | } |
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| 103 | } |
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| 104 | |
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| 105 | synchronized long getGenerationStamp() { |
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| 106 | return theBlock.getGenerationStamp(); |
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| 107 | } |
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| 108 | |
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| 109 | synchronized void updateBlock(Block b) { |
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| 110 | theBlock.setGenerationStamp(b.getGenerationStamp()); |
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| 111 | setlength(b.getNumBytes()); |
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| 112 | } |
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| 113 | |
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| 114 | synchronized long getlength() { |
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| 115 | if (!finalized) { |
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| 116 | return oStream.getLength(); |
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| 117 | } else { |
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| 118 | return theBlock.getNumBytes(); |
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| 119 | } |
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| 120 | } |
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| 121 | |
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| 122 | synchronized void setlength(long length) { |
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| 123 | if (!finalized) { |
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| 124 | oStream.setLength(length); |
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| 125 | } else { |
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| 126 | theBlock.setNumBytes(length); |
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| 127 | } |
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| 128 | } |
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| 129 | |
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| 130 | synchronized SimulatedInputStream getIStream() throws IOException { |
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| 131 | if (!finalized) { |
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| 132 | // throw new IOException("Trying to read an unfinalized block"); |
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| 133 | return new SimulatedInputStream(oStream.getLength(), DEFAULT_DATABYTE); |
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| 134 | } else { |
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| 135 | return new SimulatedInputStream(theBlock.getNumBytes(), DEFAULT_DATABYTE); |
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| 136 | } |
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| 137 | } |
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| 138 | |
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| 139 | synchronized void finalizeBlock(long finalSize) throws IOException { |
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| 140 | if (finalized) { |
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| 141 | throw new IOException( |
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| 142 | "Finalizing a block that has already been finalized" + |
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| 143 | theBlock.getBlockId()); |
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| 144 | } |
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| 145 | if (oStream == null) { |
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| 146 | DataNode.LOG.error("Null oStream on unfinalized block - bug"); |
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| 147 | throw new IOException("Unexpected error on finalize"); |
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| 148 | } |
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| 149 | |
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| 150 | if (oStream.getLength() != finalSize) { |
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| 151 | DataNode.LOG.warn("Size passed to finalize (" + finalSize + |
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| 152 | ")does not match what was written:" + oStream.getLength()); |
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| 153 | throw new IOException( |
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| 154 | "Size passed to finalize does not match the amount of data written"); |
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| 155 | } |
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| 156 | // We had allocated the expected length when block was created; |
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| 157 | // adjust if necessary |
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| 158 | long extraLen = finalSize - theBlock.getNumBytes(); |
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| 159 | if (extraLen > 0) { |
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| 160 | if (!storage.alloc(extraLen)) { |
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| 161 | DataNode.LOG.warn("Lack of free storage on a block alloc"); |
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| 162 | throw new IOException("Creating block, no free space available"); |
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| 163 | } |
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| 164 | } else { |
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| 165 | storage.free(-extraLen); |
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| 166 | } |
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| 167 | theBlock.setNumBytes(finalSize); |
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| 168 | |
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| 169 | finalized = true; |
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| 170 | oStream = null; |
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| 171 | return; |
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| 172 | } |
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| 173 | |
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| 174 | SimulatedInputStream getMetaIStream() { |
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| 175 | return new SimulatedInputStream(nullCrcFileData); |
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| 176 | } |
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| 177 | |
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| 178 | synchronized boolean isFinalized() { |
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| 179 | return finalized; |
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| 180 | } |
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| 181 | } |
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| 182 | |
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| 183 | static private class SimulatedStorage { |
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| 184 | private long capacity; // in bytes |
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| 185 | private long used; // in bytes |
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| 186 | |
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| 187 | synchronized long getFree() { |
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| 188 | return capacity - used; |
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| 189 | } |
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| 190 | |
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| 191 | synchronized long getCapacity() { |
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| 192 | return capacity; |
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| 193 | } |
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| 194 | |
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| 195 | synchronized long getUsed() { |
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| 196 | return used; |
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| 197 | } |
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| 198 | |
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| 199 | synchronized boolean alloc(long amount) { |
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| 200 | if (getFree() >= amount) { |
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| 201 | used += amount; |
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| 202 | return true; |
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| 203 | } else { |
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| 204 | return false; |
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| 205 | } |
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| 206 | } |
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| 207 | |
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| 208 | synchronized void free(long amount) { |
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| 209 | used -= amount; |
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| 210 | } |
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| 211 | |
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| 212 | SimulatedStorage(long cap) { |
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| 213 | capacity = cap; |
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| 214 | used = 0; |
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| 215 | } |
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| 216 | } |
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| 217 | |
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| 218 | private HashMap<Block, BInfo> blockMap = null; |
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| 219 | private SimulatedStorage storage = null; |
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| 220 | private String storageId; |
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| 221 | |
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| 222 | public SimulatedFSDataset(Configuration conf) throws IOException { |
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| 223 | setConf(conf); |
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| 224 | } |
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| 225 | |
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| 226 | private SimulatedFSDataset() { // real construction when setConf called.. Uggg |
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| 227 | } |
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| 228 | |
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| 229 | public Configuration getConf() { |
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| 230 | return conf; |
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| 231 | } |
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| 232 | |
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| 233 | public void setConf(Configuration iconf) { |
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| 234 | conf = iconf; |
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| 235 | storageId = conf.get("StorageId", "unknownStorageId" + |
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| 236 | new Random().nextInt()); |
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| 237 | registerMBean(storageId); |
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| 238 | storage = new SimulatedStorage( |
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| 239 | conf.getLong(CONFIG_PROPERTY_CAPACITY, DEFAULT_CAPACITY)); |
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| 240 | //DataNode.LOG.info("Starting Simulated storage; Capacity = " + getCapacity() + |
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| 241 | // "Used = " + getDfsUsed() + "Free =" + getRemaining()); |
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| 242 | |
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| 243 | blockMap = new HashMap<Block,BInfo>(); |
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| 244 | } |
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| 245 | |
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| 246 | public synchronized void injectBlocks(Block[] injectBlocks) |
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| 247 | throws IOException { |
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| 248 | if (injectBlocks != null) { |
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| 249 | for (Block b: injectBlocks) { // if any blocks in list is bad, reject list |
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| 250 | if (b == null) { |
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| 251 | throw new NullPointerException("Null blocks in block list"); |
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| 252 | } |
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| 253 | if (isValidBlock(b)) { |
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| 254 | throw new IOException("Block already exists in block list"); |
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| 255 | } |
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| 256 | } |
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| 257 | HashMap<Block, BInfo> oldBlockMap = blockMap; |
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| 258 | blockMap = |
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| 259 | new HashMap<Block,BInfo>(injectBlocks.length + oldBlockMap.size()); |
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| 260 | blockMap.putAll(oldBlockMap); |
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| 261 | for (Block b: injectBlocks) { |
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| 262 | BInfo binfo = new BInfo(b, false); |
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| 263 | blockMap.put(b, binfo); |
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| 264 | } |
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| 265 | } |
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| 266 | } |
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| 267 | |
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| 268 | public synchronized void finalizeBlock(Block b) throws IOException { |
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| 269 | BInfo binfo = blockMap.get(b); |
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| 270 | if (binfo == null) { |
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| 271 | throw new IOException("Finalizing a non existing block " + b); |
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| 272 | } |
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| 273 | binfo.finalizeBlock(b.getNumBytes()); |
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| 274 | |
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| 275 | } |
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| 276 | |
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| 277 | public synchronized void unfinalizeBlock(Block b) throws IOException { |
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| 278 | if (isBeingWritten(b)) { |
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| 279 | blockMap.remove(b); |
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| 280 | } |
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| 281 | } |
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| 282 | |
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| 283 | public synchronized Block[] getBlockReport() { |
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| 284 | Block[] blockTable = new Block[blockMap.size()]; |
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| 285 | int count = 0; |
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| 286 | for (BInfo b : blockMap.values()) { |
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| 287 | if (b.isFinalized()) { |
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| 288 | blockTable[count++] = b.theBlock; |
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| 289 | } |
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| 290 | } |
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| 291 | if (count != blockTable.length) { |
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| 292 | blockTable = Arrays.copyOf(blockTable, count); |
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| 293 | } |
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| 294 | return blockTable; |
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| 295 | } |
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| 296 | |
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| 297 | public long getCapacity() throws IOException { |
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| 298 | return storage.getCapacity(); |
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| 299 | } |
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| 300 | |
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| 301 | public long getDfsUsed() throws IOException { |
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| 302 | return storage.getUsed(); |
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| 303 | } |
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| 304 | |
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| 305 | public long getRemaining() throws IOException { |
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| 306 | return storage.getFree(); |
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| 307 | } |
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| 308 | |
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| 309 | public synchronized long getLength(Block b) throws IOException { |
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| 310 | BInfo binfo = blockMap.get(b); |
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| 311 | if (binfo == null) { |
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| 312 | throw new IOException("Finalizing a non existing block " + b); |
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| 313 | } |
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| 314 | return binfo.getlength(); |
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| 315 | } |
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| 316 | |
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| 317 | /** {@inheritDoc} */ |
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| 318 | public Block getStoredBlock(long blkid) throws IOException { |
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| 319 | Block b = new Block(blkid); |
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| 320 | BInfo binfo = blockMap.get(b); |
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| 321 | if (binfo == null) { |
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| 322 | return null; |
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| 323 | } |
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| 324 | b.setGenerationStamp(binfo.getGenerationStamp()); |
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| 325 | b.setNumBytes(binfo.getlength()); |
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| 326 | return b; |
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| 327 | } |
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| 328 | |
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| 329 | /** {@inheritDoc} */ |
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| 330 | public void updateBlock(Block oldblock, Block newblock) throws IOException { |
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| 331 | BInfo binfo = blockMap.get(newblock); |
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| 332 | if (binfo == null) { |
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| 333 | throw new IOException("BInfo not found, b=" + newblock); |
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| 334 | } |
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| 335 | binfo.updateBlock(newblock); |
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| 336 | } |
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| 337 | |
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| 338 | public synchronized void invalidate(Block[] invalidBlks) throws IOException { |
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| 339 | boolean error = false; |
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| 340 | if (invalidBlks == null) { |
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| 341 | return; |
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| 342 | } |
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| 343 | for (Block b: invalidBlks) { |
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| 344 | if (b == null) { |
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| 345 | continue; |
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| 346 | } |
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| 347 | BInfo binfo = blockMap.get(b); |
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| 348 | if (binfo == null) { |
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| 349 | error = true; |
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| 350 | DataNode.LOG.warn("Invalidate: Missing block"); |
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| 351 | continue; |
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| 352 | } |
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| 353 | storage.free(binfo.getlength()); |
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| 354 | blockMap.remove(b); |
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| 355 | } |
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| 356 | if (error) { |
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| 357 | throw new IOException("Invalidate: Missing blocks."); |
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| 358 | } |
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| 359 | } |
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| 360 | |
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| 361 | public synchronized boolean isValidBlock(Block b) { |
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| 362 | // return (blockMap.containsKey(b)); |
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| 363 | BInfo binfo = blockMap.get(b); |
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| 364 | if (binfo == null) { |
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| 365 | return false; |
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| 366 | } |
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| 367 | return binfo.isFinalized(); |
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| 368 | } |
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| 369 | |
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| 370 | /* check if a block is created but not finalized */ |
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| 371 | private synchronized boolean isBeingWritten(Block b) { |
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| 372 | BInfo binfo = blockMap.get(b); |
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| 373 | if (binfo == null) { |
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| 374 | return false; |
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| 375 | } |
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| 376 | return !binfo.isFinalized(); |
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| 377 | } |
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| 378 | |
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| 379 | public String toString() { |
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| 380 | return getStorageInfo(); |
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| 381 | } |
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| 382 | |
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| 383 | public synchronized BlockWriteStreams writeToBlock(Block b, |
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| 384 | boolean isRecovery) |
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| 385 | throws IOException { |
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| 386 | if (isValidBlock(b)) { |
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| 387 | throw new BlockAlreadyExistsException("Block " + b + |
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| 388 | " is valid, and cannot be written to."); |
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| 389 | } |
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| 390 | if (isBeingWritten(b)) { |
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| 391 | throw new BlockAlreadyExistsException("Block " + b + |
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| 392 | " is being written, and cannot be written to."); |
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| 393 | } |
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| 394 | BInfo binfo = new BInfo(b, true); |
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| 395 | blockMap.put(b, binfo); |
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| 396 | SimulatedOutputStream crcStream = new SimulatedOutputStream(); |
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| 397 | return new BlockWriteStreams(binfo.oStream, crcStream); |
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| 398 | } |
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| 399 | |
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| 400 | public synchronized InputStream getBlockInputStream(Block b) |
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| 401 | throws IOException { |
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| 402 | BInfo binfo = blockMap.get(b); |
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| 403 | if (binfo == null) { |
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| 404 | throw new IOException("No such Block " + b ); |
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| 405 | } |
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| 406 | |
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| 407 | //DataNode.LOG.info("Opening block(" + b.blkid + ") of length " + b.len); |
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| 408 | return binfo.getIStream(); |
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| 409 | } |
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| 410 | |
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| 411 | public synchronized InputStream getBlockInputStream(Block b, long seekOffset) |
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| 412 | throws IOException { |
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| 413 | InputStream result = getBlockInputStream(b); |
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| 414 | result.skip(seekOffset); |
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| 415 | return result; |
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| 416 | } |
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| 417 | |
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| 418 | /** Not supported */ |
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| 419 | public BlockInputStreams getTmpInputStreams(Block b, long blkoff, long ckoff |
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| 420 | ) throws IOException { |
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| 421 | throw new IOException("Not supported"); |
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| 422 | } |
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| 423 | |
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| 424 | /** No-op */ |
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| 425 | public void validateBlockMetadata(Block b) { |
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| 426 | } |
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| 427 | |
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| 428 | /** |
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| 429 | * Returns metaData of block b as an input stream |
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| 430 | * @param b - the block for which the metadata is desired |
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| 431 | * @return metaData of block b as an input stream |
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| 432 | * @throws IOException - block does not exist or problems accessing |
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| 433 | * the meta file |
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| 434 | */ |
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| 435 | private synchronized InputStream getMetaDataInStream(Block b) |
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| 436 | throws IOException { |
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| 437 | BInfo binfo = blockMap.get(b); |
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| 438 | if (binfo == null) { |
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| 439 | throw new IOException("No such Block " + b ); |
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| 440 | } |
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| 441 | if (!binfo.finalized) { |
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| 442 | throw new IOException("Block " + b + |
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| 443 | " is being written, its meta cannot be read"); |
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| 444 | } |
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| 445 | return binfo.getMetaIStream(); |
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| 446 | } |
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| 447 | |
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| 448 | public synchronized long getMetaDataLength(Block b) throws IOException { |
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| 449 | BInfo binfo = blockMap.get(b); |
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| 450 | if (binfo == null) { |
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| 451 | throw new IOException("No such Block " + b ); |
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| 452 | } |
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| 453 | if (!binfo.finalized) { |
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| 454 | throw new IOException("Block " + b + |
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| 455 | " is being written, its metalength cannot be read"); |
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| 456 | } |
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| 457 | return binfo.getMetaIStream().getLength(); |
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| 458 | } |
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| 459 | |
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| 460 | public MetaDataInputStream getMetaDataInputStream(Block b) |
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| 461 | throws IOException { |
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| 462 | |
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| 463 | return new MetaDataInputStream(getMetaDataInStream(b), |
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| 464 | getMetaDataLength(b)); |
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| 465 | } |
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| 466 | |
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| 467 | public synchronized boolean metaFileExists(Block b) throws IOException { |
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| 468 | if (!isValidBlock(b)) { |
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| 469 | throw new IOException("Block " + b + |
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| 470 | " is valid, and cannot be written to."); |
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| 471 | } |
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| 472 | return true; // crc exists for all valid blocks |
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| 473 | } |
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| 474 | |
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| 475 | public void checkDataDir() throws DiskErrorException { |
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| 476 | // nothing to check for simulated data set |
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| 477 | } |
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| 478 | |
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| 479 | public synchronized long getChannelPosition(Block b, |
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| 480 | BlockWriteStreams stream) |
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| 481 | throws IOException { |
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| 482 | BInfo binfo = blockMap.get(b); |
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| 483 | if (binfo == null) { |
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| 484 | throw new IOException("No such Block " + b ); |
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| 485 | } |
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| 486 | return binfo.getlength(); |
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| 487 | } |
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| 488 | |
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| 489 | public synchronized void setChannelPosition(Block b, BlockWriteStreams stream, |
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| 490 | long dataOffset, long ckOffset) |
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| 491 | throws IOException { |
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| 492 | BInfo binfo = blockMap.get(b); |
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| 493 | if (binfo == null) { |
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| 494 | throw new IOException("No such Block " + b ); |
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| 495 | } |
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| 496 | binfo.setlength(dataOffset); |
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| 497 | } |
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| 498 | |
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| 499 | /** |
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| 500 | * Simulated input and output streams |
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| 501 | * |
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| 502 | */ |
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| 503 | static private class SimulatedInputStream extends java.io.InputStream { |
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| 504 | |
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| 505 | |
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| 506 | byte theRepeatedData = 7; |
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| 507 | long length; // bytes |
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| 508 | int currentPos = 0; |
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| 509 | byte[] data = null; |
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| 510 | |
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| 511 | /** |
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| 512 | * An input stream of size l with repeated bytes |
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| 513 | * @param l |
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| 514 | * @param iRepeatedData |
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| 515 | */ |
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| 516 | SimulatedInputStream(long l, byte iRepeatedData) { |
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| 517 | length = l; |
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| 518 | theRepeatedData = iRepeatedData; |
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| 519 | } |
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| 520 | |
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| 521 | /** |
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| 522 | * An input stream of of the supplied data |
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| 523 | * |
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| 524 | * @param iData |
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| 525 | */ |
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| 526 | SimulatedInputStream(byte[] iData) { |
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| 527 | data = iData; |
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| 528 | length = data.length; |
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| 529 | |
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| 530 | } |
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| 531 | |
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| 532 | /** |
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| 533 | * |
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| 534 | * @return the lenght of the input stream |
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| 535 | */ |
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| 536 | long getLength() { |
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| 537 | return length; |
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| 538 | } |
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| 539 | |
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| 540 | @Override |
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| 541 | public int read() throws IOException { |
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| 542 | if (currentPos >= length) |
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| 543 | return -1; |
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| 544 | if (data !=null) { |
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| 545 | return data[currentPos++]; |
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| 546 | } else { |
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| 547 | currentPos++; |
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| 548 | return theRepeatedData; |
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| 549 | } |
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| 550 | } |
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| 551 | |
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| 552 | @Override |
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| 553 | public int read(byte[] b) throws IOException { |
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| 554 | |
---|
| 555 | if (b == null) { |
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| 556 | throw new NullPointerException(); |
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| 557 | } |
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| 558 | if (b.length == 0) { |
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| 559 | return 0; |
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| 560 | } |
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| 561 | if (currentPos >= length) { // EOF |
---|
| 562 | return -1; |
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| 563 | } |
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| 564 | int bytesRead = (int) Math.min(b.length, length-currentPos); |
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| 565 | if (data != null) { |
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| 566 | System.arraycopy(data, currentPos, b, 0, bytesRead); |
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| 567 | } else { // all data is zero |
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| 568 | for (int i : b) { |
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| 569 | b[i] = theRepeatedData; |
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| 570 | } |
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| 571 | } |
---|
| 572 | currentPos += bytesRead; |
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| 573 | return bytesRead; |
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| 574 | } |
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| 575 | } |
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| 576 | |
---|
| 577 | /** |
---|
| 578 | * This class implements an output stream that merely throws its data away, but records its |
---|
| 579 | * length. |
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| 580 | * |
---|
| 581 | */ |
---|
| 582 | static private class SimulatedOutputStream extends OutputStream { |
---|
| 583 | long length = 0; |
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| 584 | |
---|
| 585 | /** |
---|
| 586 | * constructor for Simulated Output Steram |
---|
| 587 | */ |
---|
| 588 | SimulatedOutputStream() { |
---|
| 589 | } |
---|
| 590 | |
---|
| 591 | /** |
---|
| 592 | * |
---|
| 593 | * @return the length of the data created so far. |
---|
| 594 | */ |
---|
| 595 | long getLength() { |
---|
| 596 | return length; |
---|
| 597 | } |
---|
| 598 | |
---|
| 599 | /** |
---|
| 600 | */ |
---|
| 601 | void setLength(long length) { |
---|
| 602 | this.length = length; |
---|
| 603 | } |
---|
| 604 | |
---|
| 605 | @Override |
---|
| 606 | public void write(int arg0) throws IOException { |
---|
| 607 | length++; |
---|
| 608 | } |
---|
| 609 | |
---|
| 610 | @Override |
---|
| 611 | public void write(byte[] b) throws IOException { |
---|
| 612 | length += b.length; |
---|
| 613 | } |
---|
| 614 | |
---|
| 615 | @Override |
---|
| 616 | public void write(byte[] b, |
---|
| 617 | int off, |
---|
| 618 | int len) throws IOException { |
---|
| 619 | length += len; |
---|
| 620 | } |
---|
| 621 | } |
---|
| 622 | |
---|
| 623 | private ObjectName mbeanName; |
---|
| 624 | |
---|
| 625 | |
---|
| 626 | |
---|
| 627 | /** |
---|
| 628 | * Register the FSDataset MBean using the name |
---|
| 629 | * "hadoop:service=DataNode,name=FSDatasetState-<storageid>" |
---|
| 630 | * We use storage id for MBean name since a minicluster within a single |
---|
| 631 | * Java VM may have multiple Simulated Datanodes. |
---|
| 632 | */ |
---|
| 633 | void registerMBean(final String storageId) { |
---|
| 634 | // We wrap to bypass standard mbean naming convetion. |
---|
| 635 | // This wraping can be removed in java 6 as it is more flexible in |
---|
| 636 | // package naming for mbeans and their impl. |
---|
| 637 | StandardMBean bean; |
---|
| 638 | |
---|
| 639 | try { |
---|
| 640 | bean = new StandardMBean(this,FSDatasetMBean.class); |
---|
| 641 | mbeanName = MBeanUtil.registerMBean("DataNode", |
---|
| 642 | "FSDatasetState-" + storageId, bean); |
---|
| 643 | } catch (NotCompliantMBeanException e) { |
---|
| 644 | e.printStackTrace(); |
---|
| 645 | } |
---|
| 646 | |
---|
| 647 | DataNode.LOG.info("Registered FSDatasetStatusMBean"); |
---|
| 648 | } |
---|
| 649 | |
---|
| 650 | public void shutdown() { |
---|
| 651 | if (mbeanName != null) |
---|
| 652 | MBeanUtil.unregisterMBean(mbeanName); |
---|
| 653 | } |
---|
| 654 | |
---|
| 655 | public String getStorageInfo() { |
---|
| 656 | return "Simulated FSDataset-" + storageId; |
---|
| 657 | } |
---|
| 658 | } |
---|