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/**
*
* 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.hbase.io.hfile;
import java.io.ByteArrayInputStream;
import java.io.Closeable;
import java.io.DataInput;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.SequenceInputStream;
import java.lang.reflect.Method;
import java.net.InetSocketAddress;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Comparator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.SortedMap;
import java.util.TreeMap;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicLong;
import org.apache.hadoop.hbase.util.ByteStringer;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.hbase.classification.InterfaceAudience;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FSDataInputStream;
import org.apache.hadoop.fs.FSDataOutputStream;
import org.apache.hadoop.fs.FileStatus;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.apache.hadoop.fs.PathFilter;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.KeyValue.KVComparator;
import org.apache.hadoop.hbase.fs.HFileSystem;
import org.apache.hadoop.hbase.io.FSDataInputStreamWrapper;
import org.apache.hadoop.hbase.io.compress.Compression;
import org.apache.hadoop.hbase.io.encoding.DataBlockEncoding;
import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos;
import org.apache.hadoop.hbase.protobuf.generated.HBaseProtos.BytesBytesPair;
import org.apache.hadoop.hbase.protobuf.generated.HFileProtos;
import org.apache.hadoop.hbase.util.BloomFilterWriter;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.ChecksumType;
import org.apache.hadoop.hbase.util.FSUtils;
import org.apache.hadoop.io.Writable;
import com.google.common.base.Preconditions;
import com.google.common.collect.Lists;
/**
* File format for hbase.
* A file of sorted key/value pairs. Both keys and values are byte arrays.
*
* The memory footprint of a HFile includes the following (below is taken from the
* TFile documentation
* but applies also to HFile):
*
* - Some constant overhead of reading or writing a compressed block.
*
* - Each compressed block requires one compression/decompression codec for
* I/O.
*
- Temporary space to buffer the key.
*
- Temporary space to buffer the value.
*
* - HFile index, which is proportional to the total number of Data Blocks.
* The total amount of memory needed to hold the index can be estimated as
* (56+AvgKeySize)*NumBlocks.
*
* Suggestions on performance optimization.
*
* - Minimum block size. We recommend a setting of minimum block size between
* 8KB to 1MB for general usage. Larger block size is preferred if files are
* primarily for sequential access. However, it would lead to inefficient random
* access (because there are more data to decompress). Smaller blocks are good
* for random access, but require more memory to hold the block index, and may
* be slower to create (because we must flush the compressor stream at the
* conclusion of each data block, which leads to an FS I/O flush). Further, due
* to the internal caching in Compression codec, the smallest possible block
* size would be around 20KB-30KB.
*
- The current implementation does not offer true multi-threading for
* reading. The implementation uses FSDataInputStream seek()+read(), which is
* shown to be much faster than positioned-read call in single thread mode.
* However, it also means that if multiple threads attempt to access the same
* HFile (using multiple scanners) simultaneously, the actual I/O is carried out
* sequentially even if they access different DFS blocks (Reexamine! pread seems
* to be 10% faster than seek+read in my testing -- stack).
*
- Compression codec. Use "none" if the data is not very compressable (by
* compressable, I mean a compression ratio at least 2:1). Generally, use "lzo"
* as the starting point for experimenting. "gz" overs slightly better
* compression ratio over "lzo" but requires 4x CPU to compress and 2x CPU to
* decompress, comparing to "lzo".
*
*
* For more on the background behind HFile, see HBASE-61.
*
* File is made of data blocks followed by meta data blocks (if any), a fileinfo
* block, data block index, meta data block index, and a fixed size trailer
* which records the offsets at which file changes content type.
*
<data blocks><meta blocks><fileinfo><data index><meta index><trailer>
* Each block has a bit of magic at its start. Block are comprised of
* key/values. In data blocks, they are both byte arrays. Metadata blocks are
* a String key and a byte array value. An empty file looks like this:
* <fileinfo><trailer>
. That is, there are not data nor meta
* blocks present.
*
* TODO: Do scanners need to be able to take a start and end row?
* TODO: Should BlockIndex know the name of its file? Should it have a Path
* that points at its file say for the case where an index lives apart from
* an HFile instance?
*/
@InterfaceAudience.Private
public class HFile {
static final Log LOG = LogFactory.getLog(HFile.class);
/**
* Maximum length of key in HFile.
*/
public final static int MAXIMUM_KEY_LENGTH = Integer.MAX_VALUE;
/**
* Default compression: none.
*/
public final static Compression.Algorithm DEFAULT_COMPRESSION_ALGORITHM =
Compression.Algorithm.NONE;
/** Minimum supported HFile format version */
public static final int MIN_FORMAT_VERSION = 2;
/** Maximum supported HFile format version
*/
public static final int MAX_FORMAT_VERSION = 3;
/**
* Minimum HFile format version with support for persisting cell tags
*/
public static final int MIN_FORMAT_VERSION_WITH_TAGS = 3;
/** Default compression name: none. */
public final static String DEFAULT_COMPRESSION =
DEFAULT_COMPRESSION_ALGORITHM.getName();
/** Meta data block name for bloom filter bits. */
public static final String BLOOM_FILTER_DATA_KEY = "BLOOM_FILTER_DATA";
/**
* We assume that HFile path ends with
* ROOT_DIR/TABLE_NAME/REGION_NAME/CF_NAME/HFILE, so it has at least this
* many levels of nesting. This is needed for identifying table and CF name
* from an HFile path.
*/
public final static int MIN_NUM_HFILE_PATH_LEVELS = 5;
/**
* The number of bytes per checksum.
*/
public static final int DEFAULT_BYTES_PER_CHECKSUM = 16 * 1024;
public static final ChecksumType DEFAULT_CHECKSUM_TYPE = ChecksumType.CRC32;
// For measuring number of checksum failures
static final AtomicLong checksumFailures = new AtomicLong();
// for test purpose
public static final AtomicLong dataBlockReadCnt = new AtomicLong(0);
/**
* Number of checksum verification failures. It also
* clears the counter.
*/
public static final long getChecksumFailuresCount() {
return checksumFailures.getAndSet(0);
}
/** API required to write an {@link HFile} */
public interface Writer extends Closeable {
/** Add an element to the file info map. */
void appendFileInfo(byte[] key, byte[] value) throws IOException;
void append(KeyValue kv) throws IOException;
void append(byte[] key, byte[] value) throws IOException;
void append (byte[] key, byte[] value, byte[] tag) throws IOException;
/** @return the path to this {@link HFile} */
Path getPath();
/**
* Adds an inline block writer such as a multi-level block index writer or
* a compound Bloom filter writer.
*/
void addInlineBlockWriter(InlineBlockWriter bloomWriter);
// The below three methods take Writables. We'd like to undo Writables but undoing the below would be pretty
// painful. Could take a byte [] or a Message but we want to be backward compatible around hfiles so would need
// to map between Message and Writable or byte [] and current Writable serialization. This would be a bit of work
// to little gain. Thats my thinking at moment. St.Ack 20121129
void appendMetaBlock(String bloomFilterMetaKey, Writable metaWriter);
/**
* Store general Bloom filter in the file. This does not deal with Bloom filter
* internals but is necessary, since Bloom filters are stored differently
* in HFile version 1 and version 2.
*/
void addGeneralBloomFilter(BloomFilterWriter bfw);
/**
* Store delete family Bloom filter in the file, which is only supported in
* HFile V2.
*/
void addDeleteFamilyBloomFilter(BloomFilterWriter bfw) throws IOException;
/**
* Return the file context for the HFile this writer belongs to
*/
HFileContext getFileContext();
}
/**
* This variety of ways to construct writers is used throughout the code, and
* we want to be able to swap writer implementations.
*/
public static abstract class WriterFactory {
protected final Configuration conf;
protected final CacheConfig cacheConf;
protected FileSystem fs;
protected Path path;
protected FSDataOutputStream ostream;
protected KVComparator comparator = KeyValue.COMPARATOR;
protected InetSocketAddress[] favoredNodes;
private HFileContext fileContext;
protected boolean shouldDropBehind = false;
WriterFactory(Configuration conf, CacheConfig cacheConf) {
this.conf = conf;
this.cacheConf = cacheConf;
}
public WriterFactory withPath(FileSystem fs, Path path) {
Preconditions.checkNotNull(fs);
Preconditions.checkNotNull(path);
this.fs = fs;
this.path = path;
return this;
}
public WriterFactory withOutputStream(FSDataOutputStream ostream) {
Preconditions.checkNotNull(ostream);
this.ostream = ostream;
return this;
}
public WriterFactory withComparator(KVComparator comparator) {
Preconditions.checkNotNull(comparator);
this.comparator = comparator;
return this;
}
public WriterFactory withFavoredNodes(InetSocketAddress[] favoredNodes) {
// Deliberately not checking for null here.
this.favoredNodes = favoredNodes;
return this;
}
public WriterFactory withFileContext(HFileContext fileContext) {
this.fileContext = fileContext;
return this;
}
public WriterFactory withShouldDropCacheBehind(boolean shouldDropBehind) {
this.shouldDropBehind = shouldDropBehind;
return this;
}
public Writer create() throws IOException {
if ((path != null ? 1 : 0) + (ostream != null ? 1 : 0) != 1) {
throw new AssertionError("Please specify exactly one of " +
"filesystem/path or path");
}
if (path != null) {
ostream = AbstractHFileWriter.createOutputStream(conf, fs, path, favoredNodes);
try {
Class outStreamClass = ostream.getClass();
try {
Method m = outStreamClass.getDeclaredMethod("setDropBehind",
new Class[]{ boolean.class });
m.invoke(ostream, new Object[] {
shouldDropBehind && cacheConf.shouldDropBehindCompaction() });
} catch (NoSuchMethodException e) {
// Not supported, we can just ignore it
} catch (Exception e) {
if (LOG.isDebugEnabled()) {
LOG.debug("Failed to invoke output stream's setDropBehind method, continuing");
}
}
} catch (UnsupportedOperationException uoe) {
LOG.debug("Unable to set drop behind on " + path, uoe);
}
}
return createWriter(fs, path, ostream,
comparator, fileContext);
}
protected abstract Writer createWriter(FileSystem fs, Path path, FSDataOutputStream ostream,
KVComparator comparator, HFileContext fileContext) throws IOException;
}
/** The configuration key for HFile version to use for new files */
public static final String FORMAT_VERSION_KEY = "hfile.format.version";
public static int getFormatVersion(Configuration conf) {
int version = conf.getInt(FORMAT_VERSION_KEY, MAX_FORMAT_VERSION);
checkFormatVersion(version);
return version;
}
/**
* Returns the factory to be used to create {@link HFile} writers.
* Disables block cache access for all writers created through the
* returned factory.
*/
public static final WriterFactory getWriterFactoryNoCache(Configuration
conf) {
Configuration tempConf = new Configuration(conf);
tempConf.setFloat(HConstants.HFILE_BLOCK_CACHE_SIZE_KEY, 0.0f);
return HFile.getWriterFactory(conf, new CacheConfig(tempConf));
}
/**
* Returns the factory to be used to create {@link HFile} writers
*/
public static final WriterFactory getWriterFactory(Configuration conf,
CacheConfig cacheConf) {
int version = getFormatVersion(conf);
switch (version) {
case 2:
return new HFileWriterV2.WriterFactoryV2(conf, cacheConf);
case 3:
return new HFileWriterV3.WriterFactoryV3(conf, cacheConf);
default:
throw new IllegalArgumentException("Cannot create writer for HFile " +
"format version " + version);
}
}
/** An abstraction used by the block index */
public interface CachingBlockReader {
HFileBlock readBlock(long offset, long onDiskBlockSize,
boolean cacheBlock, final boolean pread, final boolean isCompaction,
final boolean updateCacheMetrics, BlockType expectedBlockType)
throws IOException;
}
/** An interface used by clients to open and iterate an {@link HFile}. */
public interface Reader extends Closeable, CachingBlockReader {
/**
* Returns this reader's "name". Usually the last component of the path.
* Needs to be constant as the file is being moved to support caching on
* write.
*/
String getName();
KVComparator getComparator();
HFileScanner getScanner(boolean cacheBlocks,
final boolean pread, final boolean isCompaction);
ByteBuffer getMetaBlock(String metaBlockName,
boolean cacheBlock) throws IOException;
Map loadFileInfo() throws IOException;
byte[] getLastKey();
byte[] midkey() throws IOException;
long length();
long getEntries();
byte[] getFirstKey();
long indexSize();
byte[] getFirstRowKey();
byte[] getLastRowKey();
FixedFileTrailer getTrailer();
HFileBlockIndex.BlockIndexReader getDataBlockIndexReader();
HFileScanner getScanner(boolean cacheBlocks, boolean pread);
Compression.Algorithm getCompressionAlgorithm();
/**
* Retrieves general Bloom filter metadata as appropriate for each
* {@link HFile} version.
* Knows nothing about how that metadata is structured.
*/
DataInput getGeneralBloomFilterMetadata() throws IOException;
/**
* Retrieves delete family Bloom filter metadata as appropriate for each
* {@link HFile} version.
* Knows nothing about how that metadata is structured.
*/
DataInput getDeleteBloomFilterMetadata() throws IOException;
Path getPath();
/** Close method with optional evictOnClose */
void close(boolean evictOnClose) throws IOException;
DataBlockEncoding getDataBlockEncoding();
boolean hasMVCCInfo();
/**
* Return the file context of the HFile this reader belongs to
*/
HFileContext getFileContext();
}
/**
* Method returns the reader given the specified arguments.
* TODO This is a bad abstraction. See HBASE-6635.
*
* @param path hfile's path
* @param fsdis stream of path's file
* @param size max size of the trailer.
* @param cacheConf Cache configuation values, cannot be null.
* @param hfs
* @return an appropriate instance of HFileReader
* @throws IOException If file is invalid, will throw CorruptHFileException flavored IOException
*/
private static Reader pickReaderVersion(Path path, FSDataInputStreamWrapper fsdis,
long size, CacheConfig cacheConf, HFileSystem hfs, Configuration conf) throws IOException {
FixedFileTrailer trailer = null;
try {
boolean isHBaseChecksum = fsdis.shouldUseHBaseChecksum();
assert !isHBaseChecksum; // Initially we must read with FS checksum.
trailer = FixedFileTrailer.readFromStream(fsdis.getStream(isHBaseChecksum), size);
switch (trailer.getMajorVersion()) {
case 2:
return new HFileReaderV2(path, trailer, fsdis, size, cacheConf, hfs, conf);
case 3 :
return new HFileReaderV3(path, trailer, fsdis, size, cacheConf, hfs, conf);
default:
throw new IllegalArgumentException("Invalid HFile version " + trailer.getMajorVersion());
}
} catch (Throwable t) {
try {
fsdis.close();
} catch (Throwable t2) {
LOG.warn("Error closing fsdis FSDataInputStreamWrapper", t2);
}
throw new CorruptHFileException("Problem reading HFile Trailer from file " + path, t);
}
}
/**
* @param fs A file system
* @param path Path to HFile
* @param fsdis a stream of path's file
* @param size max size of the trailer.
* @param cacheConf Cache configuration for hfile's contents
* @param conf Configuration
* @return A version specific Hfile Reader
* @throws IOException If file is invalid, will throw CorruptHFileException flavored IOException
*/
public static Reader createReader(FileSystem fs, Path path,
FSDataInputStreamWrapper fsdis, long size, CacheConfig cacheConf, Configuration conf)
throws IOException {
HFileSystem hfs = null;
// If the fs is not an instance of HFileSystem, then create an
// instance of HFileSystem that wraps over the specified fs.
// In this case, we will not be able to avoid checksumming inside
// the filesystem.
if (!(fs instanceof HFileSystem)) {
hfs = new HFileSystem(fs);
} else {
hfs = (HFileSystem)fs;
}
return pickReaderVersion(path, fsdis, size, cacheConf, hfs, conf);
}
/**
*
* @param fs filesystem
* @param path Path to file to read
* @param cacheConf This must not be null. @see {@link org.apache.hadoop.hbase.io.hfile.CacheConfig#CacheConfig(Configuration)}
* @return an active Reader instance
* @throws IOException Will throw a CorruptHFileException (DoNotRetryIOException subtype) if hfile is corrupt/invalid.
*/
public static Reader createReader(
FileSystem fs, Path path, CacheConfig cacheConf, Configuration conf) throws IOException {
Preconditions.checkNotNull(cacheConf, "Cannot create Reader with null CacheConf");
FSDataInputStreamWrapper stream = new FSDataInputStreamWrapper(fs, path);
return pickReaderVersion(path, stream, fs.getFileStatus(path).getLen(),
cacheConf, stream.getHfs(), conf);
}
/**
* This factory method is used only by unit tests
*/
static Reader createReaderFromStream(Path path,
FSDataInputStream fsdis, long size, CacheConfig cacheConf, Configuration conf)
throws IOException {
FSDataInputStreamWrapper wrapper = new FSDataInputStreamWrapper(fsdis);
return pickReaderVersion(path, wrapper, size, cacheConf, null, conf);
}
/**
* Returns true if the specified file has a valid HFile Trailer.
* @param fs filesystem
* @param path Path to file to verify
* @return true if the file has a valid HFile Trailer, otherwise false
* @throws IOException if failed to read from the underlying stream
*/
public static boolean isHFileFormat(final FileSystem fs, final Path path) throws IOException {
return isHFileFormat(fs, fs.getFileStatus(path));
}
/**
* Returns true if the specified file has a valid HFile Trailer.
* @param fs filesystem
* @param fileStatus the file to verify
* @return true if the file has a valid HFile Trailer, otherwise false
* @throws IOException if failed to read from the underlying stream
*/
public static boolean isHFileFormat(final FileSystem fs, final FileStatus fileStatus)
throws IOException {
final Path path = fileStatus.getPath();
final long size = fileStatus.getLen();
FSDataInputStreamWrapper fsdis = new FSDataInputStreamWrapper(fs, path);
try {
boolean isHBaseChecksum = fsdis.shouldUseHBaseChecksum();
assert !isHBaseChecksum; // Initially we must read with FS checksum.
FixedFileTrailer.readFromStream(fsdis.getStream(isHBaseChecksum), size);
return true;
} catch (IllegalArgumentException e) {
return false;
} catch (IOException e) {
throw e;
} finally {
try {
fsdis.close();
} catch (Throwable t) {
LOG.warn("Error closing fsdis FSDataInputStreamWrapper: " + path, t);
}
}
}
/**
* Metadata for this file. Conjured by the writer. Read in by the reader.
*/
public static class FileInfo implements SortedMap {
static final String RESERVED_PREFIX = "hfile.";
static final byte[] RESERVED_PREFIX_BYTES = Bytes.toBytes(RESERVED_PREFIX);
static final byte [] LASTKEY = Bytes.toBytes(RESERVED_PREFIX + "LASTKEY");
static final byte [] AVG_KEY_LEN = Bytes.toBytes(RESERVED_PREFIX + "AVG_KEY_LEN");
static final byte [] AVG_VALUE_LEN = Bytes.toBytes(RESERVED_PREFIX + "AVG_VALUE_LEN");
static final byte [] COMPARATOR = Bytes.toBytes(RESERVED_PREFIX + "COMPARATOR");
static final byte [] TAGS_COMPRESSED = Bytes.toBytes(RESERVED_PREFIX + "TAGS_COMPRESSED");
public static final byte [] MAX_TAGS_LEN = Bytes.toBytes(RESERVED_PREFIX + "MAX_TAGS_LEN");
private final SortedMap map = new TreeMap(Bytes.BYTES_COMPARATOR);
public FileInfo() {
super();
}
/**
* Append the given key/value pair to the file info, optionally checking the
* key prefix.
*
* @param k key to add
* @param v value to add
* @param checkPrefix whether to check that the provided key does not start
* with the reserved prefix
* @return this file info object
* @throws IOException if the key or value is invalid
*/
public FileInfo append(final byte[] k, final byte[] v,
final boolean checkPrefix) throws IOException {
if (k == null || v == null) {
throw new NullPointerException("Key nor value may be null");
}
if (checkPrefix && isReservedFileInfoKey(k)) {
throw new IOException("Keys with a " + FileInfo.RESERVED_PREFIX
+ " are reserved");
}
put(k, v);
return this;
}
public void clear() {
this.map.clear();
}
public Comparator comparator() {
return map.comparator();
}
public boolean containsKey(Object key) {
return map.containsKey(key);
}
public boolean containsValue(Object value) {
return map.containsValue(value);
}
public Set> entrySet() {
return map.entrySet();
}
public boolean equals(Object o) {
return map.equals(o);
}
public byte[] firstKey() {
return map.firstKey();
}
public byte[] get(Object key) {
return map.get(key);
}
public int hashCode() {
return map.hashCode();
}
public SortedMap headMap(byte[] toKey) {
return this.map.headMap(toKey);
}
public boolean isEmpty() {
return map.isEmpty();
}
public Set keySet() {
return map.keySet();
}
public byte[] lastKey() {
return map.lastKey();
}
public byte[] put(byte[] key, byte[] value) {
return this.map.put(key, value);
}
public void putAll(Map m) {
this.map.putAll(m);
}
public byte[] remove(Object key) {
return this.map.remove(key);
}
public int size() {
return map.size();
}
public SortedMap subMap(byte[] fromKey, byte[] toKey) {
return this.map.subMap(fromKey, toKey);
}
public SortedMap tailMap(byte[] fromKey) {
return this.map.tailMap(fromKey);
}
public Collection values() {
return map.values();
}
/**
* Write out this instance on the passed in out stream.
* We write it as a protobuf.
* @param out
* @throws IOException
* @see #read(DataInputStream)
*/
void write(final DataOutputStream out) throws IOException {
HFileProtos.FileInfoProto.Builder builder = HFileProtos.FileInfoProto.newBuilder();
for (Map.Entry e: this.map.entrySet()) {
HBaseProtos.BytesBytesPair.Builder bbpBuilder = HBaseProtos.BytesBytesPair.newBuilder();
bbpBuilder.setFirst(ByteStringer.wrap(e.getKey()));
bbpBuilder.setSecond(ByteStringer.wrap(e.getValue()));
builder.addMapEntry(bbpBuilder.build());
}
out.write(ProtobufUtil.PB_MAGIC);
builder.build().writeDelimitedTo(out);
}
/**
* Populate this instance with what we find on the passed in in stream.
* Can deserialize protobuf of old Writables format.
* @param in
* @throws IOException
* @see #write(DataOutputStream)
*/
void read(final DataInputStream in) throws IOException {
// This code is tested over in TestHFileReaderV1 where we read an old hfile w/ this new code.
int pblen = ProtobufUtil.lengthOfPBMagic();
byte [] pbuf = new byte[pblen];
if (in.markSupported()) in.mark(pblen);
int read = in.read(pbuf);
if (read != pblen) throw new IOException("read=" + read + ", wanted=" + pblen);
if (ProtobufUtil.isPBMagicPrefix(pbuf)) {
parsePB(HFileProtos.FileInfoProto.parseDelimitedFrom(in));
} else {
if (in.markSupported()) {
in.reset();
parseWritable(in);
} else {
// We cannot use BufferedInputStream, it consumes more than we read from the underlying IS
ByteArrayInputStream bais = new ByteArrayInputStream(pbuf);
SequenceInputStream sis = new SequenceInputStream(bais, in); // Concatenate input streams
// TODO: Am I leaking anything here wrapping the passed in stream? We are not calling close on the wrapped
// streams but they should be let go after we leave this context? I see that we keep a reference to the
// passed in inputstream but since we no longer have a reference to this after we leave, we should be ok.
parseWritable(new DataInputStream(sis));
}
}
}
/** Now parse the old Writable format. It was a list of Map entries. Each map entry was a key and a value of
* a byte []. The old map format had a byte before each entry that held a code which was short for the key or
* value type. We know it was a byte [] so in below we just read and dump it.
* @throws IOException
*/
void parseWritable(final DataInputStream in) throws IOException {
// First clear the map. Otherwise we will just accumulate entries every time this method is called.
this.map.clear();
// Read the number of entries in the map
int entries = in.readInt();
// Then read each key/value pair
for (int i = 0; i < entries; i++) {
byte [] key = Bytes.readByteArray(in);
// We used to read a byte that encoded the class type. Read and ignore it because it is always byte [] in hfile
in.readByte();
byte [] value = Bytes.readByteArray(in);
this.map.put(key, value);
}
}
/**
* Fill our map with content of the pb we read off disk
* @param fip protobuf message to read
*/
void parsePB(final HFileProtos.FileInfoProto fip) {
this.map.clear();
for (BytesBytesPair pair: fip.getMapEntryList()) {
this.map.put(pair.getFirst().toByteArray(), pair.getSecond().toByteArray());
}
}
}
/** Return true if the given file info key is reserved for internal use. */
public static boolean isReservedFileInfoKey(byte[] key) {
return Bytes.startsWith(key, FileInfo.RESERVED_PREFIX_BYTES);
}
/**
* Get names of supported compression algorithms. The names are acceptable by
* HFile.Writer.
*
* @return Array of strings, each represents a supported compression
* algorithm. Currently, the following compression algorithms are
* supported.
*
* - "none" - No compression.
*
- "gz" - GZIP compression.
*
*/
public static String[] getSupportedCompressionAlgorithms() {
return Compression.getSupportedAlgorithms();
}
// Utility methods.
/*
* @param l Long to convert to an int.
* @return l cast as an int.
*/
static int longToInt(final long l) {
// Expecting the size() of a block not exceeding 4GB. Assuming the
// size() will wrap to negative integer if it exceeds 2GB (From tfile).
return (int)(l & 0x00000000ffffffffL);
}
/**
* Returns all files belonging to the given region directory. Could return an
* empty list.
*
* @param fs The file system reference.
* @param regionDir The region directory to scan.
* @return The list of files found.
* @throws IOException When scanning the files fails.
*/
static List getStoreFiles(FileSystem fs, Path regionDir)
throws IOException {
List res = new ArrayList();
PathFilter dirFilter = new FSUtils.DirFilter(fs);
FileStatus[] familyDirs = fs.listStatus(regionDir, dirFilter);
for(FileStatus dir : familyDirs) {
FileStatus[] files = fs.listStatus(dir.getPath());
for (FileStatus file : files) {
if (!file.isDir()) {
res.add(file.getPath());
}
}
}
return res;
}
/**
* Checks the given {@link HFile} format version, and throws an exception if
* invalid. Note that if the version number comes from an input file and has
* not been verified, the caller needs to re-throw an {@link IOException} to
* indicate that this is not a software error, but corrupted input.
*
* @param version an HFile version
* @throws IllegalArgumentException if the version is invalid
*/
public static void checkFormatVersion(int version)
throws IllegalArgumentException {
if (version < MIN_FORMAT_VERSION || version > MAX_FORMAT_VERSION) {
throw new IllegalArgumentException("Invalid HFile version: " + version
+ " (expected to be " + "between " + MIN_FORMAT_VERSION + " and "
+ MAX_FORMAT_VERSION + ")");
}
}
public static void main(String[] args) throws Exception {
// delegate to preserve old behavior
HFilePrettyPrinter.main(args);
}
}