| /** |
| * 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.hdfs.protocol; |
| |
| import java.io.*; |
| import java.util.regex.Matcher; |
| import java.util.regex.Pattern; |
| |
| import org.apache.hadoop.classification.InterfaceAudience; |
| import org.apache.hadoop.classification.InterfaceStability; |
| import org.apache.hadoop.io.*; |
| |
| import javax.annotation.Nonnull; |
| |
| /************************************************** |
| * A Block is a Hadoop FS primitive, identified by a |
| * long. |
| * |
| **************************************************/ |
| @InterfaceAudience.Private |
| @InterfaceStability.Evolving |
| public class Block implements Writable, Comparable<Block> { |
| public static final String BLOCK_FILE_PREFIX = "blk_"; |
| public static final String METADATA_EXTENSION = ".meta"; |
| static { // register a ctor |
| WritableFactories.setFactory(Block.class, new WritableFactory() { |
| @Override |
| public Writable newInstance() { return new Block(); } |
| }); |
| } |
| |
| public static final Pattern blockFilePattern = Pattern |
| .compile(BLOCK_FILE_PREFIX + "(-??\\d++)$"); |
| public static final Pattern metaFilePattern = Pattern |
| .compile(BLOCK_FILE_PREFIX + "(-??\\d++)_(\\d++)\\" + METADATA_EXTENSION |
| + "$"); |
| public static final Pattern metaOrBlockFilePattern = Pattern |
| .compile(BLOCK_FILE_PREFIX + "(-??\\d++)(_(\\d++)\\" + METADATA_EXTENSION |
| + ")?$"); |
| |
| public static boolean isBlockFilename(File f) { |
| String name = f.getName(); |
| return blockFilePattern.matcher(name).matches(); |
| } |
| |
| public static long filename2id(String name) { |
| Matcher m = blockFilePattern.matcher(name); |
| return m.matches() ? Long.parseLong(m.group(1)) : 0; |
| } |
| |
| public static boolean isMetaFilename(String name) { |
| return metaFilePattern.matcher(name).matches(); |
| } |
| |
| public static File metaToBlockFile(File metaFile) { |
| return new File(metaFile.getParent(), metaFile.getName().substring( |
| 0, metaFile.getName().lastIndexOf('_'))); |
| } |
| |
| /** |
| * Get generation stamp from the name of the metafile name |
| */ |
| public static long getGenerationStamp(String metaFile) { |
| Matcher m = metaFilePattern.matcher(metaFile); |
| return m.matches() ? Long.parseLong(m.group(2)) |
| : HdfsConstants.GRANDFATHER_GENERATION_STAMP; |
| } |
| |
| /** |
| * Get the blockId from the name of the meta or block file |
| */ |
| public static long getBlockId(String metaOrBlockFile) { |
| Matcher m = metaOrBlockFilePattern.matcher(metaOrBlockFile); |
| return m.matches() ? Long.parseLong(m.group(1)) : 0; |
| } |
| |
| private long blockId; |
| private long numBytes; |
| private long generationStamp; |
| |
| public Block() {this(0, 0, 0);} |
| |
| public Block(final long blkid, final long len, final long generationStamp) { |
| set(blkid, len, generationStamp); |
| } |
| |
| public Block(final long blkid) { |
| this(blkid, 0, HdfsConstants.GRANDFATHER_GENERATION_STAMP); |
| } |
| |
| public Block(Block blk) { |
| this(blk.blockId, blk.numBytes, blk.generationStamp); |
| } |
| |
| /** |
| * Find the blockid from the given filename |
| */ |
| public Block(File f, long len, long genstamp) { |
| this(filename2id(f.getName()), len, genstamp); |
| } |
| |
| public void set(long blkid, long len, long genStamp) { |
| this.blockId = blkid; |
| this.numBytes = len; |
| this.generationStamp = genStamp; |
| } |
| /** |
| */ |
| public long getBlockId() { |
| return blockId; |
| } |
| |
| public void setBlockId(long bid) { |
| blockId = bid; |
| } |
| |
| /** |
| */ |
| public String getBlockName() { |
| return new StringBuilder().append(BLOCK_FILE_PREFIX) |
| .append(blockId).toString(); |
| } |
| |
| /** |
| */ |
| public long getNumBytes() { |
| return numBytes; |
| } |
| public void setNumBytes(long len) { |
| this.numBytes = len; |
| } |
| |
| public long getGenerationStamp() { |
| return generationStamp; |
| } |
| |
| public void setGenerationStamp(long stamp) { |
| generationStamp = stamp; |
| } |
| |
| /** |
| * A helper method to output the string representation of the Block portion of |
| * a derived class' instance. |
| * |
| * @param b the target object |
| * @return the string representation of the block |
| */ |
| public static String toString(final Block b) { |
| StringBuilder sb = new StringBuilder(); |
| sb.append(BLOCK_FILE_PREFIX). |
| append(b.blockId).append("_"). |
| append(b.generationStamp); |
| return sb.toString(); |
| } |
| |
| /** |
| */ |
| @Override |
| public String toString() { |
| return toString(this); |
| } |
| |
| public void appendStringTo(StringBuilder sb) { |
| sb.append(BLOCK_FILE_PREFIX) |
| .append(blockId) |
| .append("_") |
| .append(getGenerationStamp()); |
| } |
| |
| |
| ///////////////////////////////////// |
| // Writable |
| ///////////////////////////////////// |
| @Override // Writable |
| public void write(DataOutput out) throws IOException { |
| writeHelper(out); |
| } |
| |
| @Override // Writable |
| public void readFields(DataInput in) throws IOException { |
| readHelper(in); |
| } |
| |
| final void writeHelper(DataOutput out) throws IOException { |
| out.writeLong(blockId); |
| out.writeLong(numBytes); |
| out.writeLong(generationStamp); |
| } |
| |
| final void readHelper(DataInput in) throws IOException { |
| this.blockId = in.readLong(); |
| this.numBytes = in.readLong(); |
| this.generationStamp = in.readLong(); |
| if (numBytes < 0) { |
| throw new IOException("Unexpected block size: " + numBytes); |
| } |
| } |
| |
| // write only the identifier part of the block |
| public void writeId(DataOutput out) throws IOException { |
| out.writeLong(blockId); |
| out.writeLong(generationStamp); |
| } |
| |
| // Read only the identifier part of the block |
| public void readId(DataInput in) throws IOException { |
| this.blockId = in.readLong(); |
| this.generationStamp = in.readLong(); |
| } |
| |
| @Override // Comparable |
| public int compareTo(@Nonnull Block b) { |
| return blockId < b.blockId ? -1 : |
| blockId > b.blockId ? 1 : 0; |
| } |
| |
| @Override // Object |
| public boolean equals(Object o) { |
| return this == o || o instanceof Block && compareTo((Block) o) == 0; |
| } |
| |
| /** |
| * @return true if the two blocks have the same block ID and the same |
| * generation stamp, or if both blocks are null. |
| */ |
| public static boolean matchingIdAndGenStamp(Block a, Block b) { |
| if (a == b) return true; // same block, or both null |
| // only one null |
| return !(a == null || b == null) && |
| a.blockId == b.blockId && |
| a.generationStamp == b.generationStamp; |
| } |
| |
| @Override // Object |
| public int hashCode() { |
| //GenerationStamp is IRRELEVANT and should not be used here |
| return (int)(blockId^(blockId>>>32)); |
| } |
| } |