HFileReaderImpl (Apache HBase 2.0.6 API)

java.lang.Object
- org.apache.hadoop.hbase.io.hfile.HFileReaderImpl

All Implemented Interfaces:

Closeable, AutoCloseable, org.apache.hadoop.conf.Configurable, HFile.CachingBlockReader, HFile.Reader
```
@InterfaceAudience.Private
public class HFileReaderImpl
extends Object
implements HFile.Reader, org.apache.hadoop.conf.Configurable
```
Implementation that can handle all hfile versions of HFile.Reader.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`HFileReaderImpl.BlockIndexNotLoadedException`
`protected static class`	`HFileReaderImpl.EncodedScanner` Scanner that operates on encoded data blocks.
`protected static class`	`HFileReaderImpl.HFileScannerImpl`
`static class`	`HFileReaderImpl.NotSeekedException` An exception thrown when an operation requiring a scanner to be seeked is invoked on a scanner that is not seeked.

Field Summary

Fields
Modifier and Type	Field and Description
`private int`	`avgKeyLen` Average key length read from file info
`private int`	`avgValueLen` Average value length read from file info
`private CacheConfig`	`cacheConf` Block cache configuration.
`private CellComparator`	`comparator` Key comparator
`private Compression.Algorithm`	`compressAlgo` Filled when we read in the trailer.
`private org.apache.hadoop.conf.Configuration`	`conf`
`private HFileDataBlockEncoder`	`dataBlockEncoder` What kind of data block encoding should be used while reading, writing, and handling cache.
`private HFileBlockIndex.CellBasedKeyBlockIndexReader`	`dataBlockIndexReader` Data block index reader keeping the root data index in memory
`protected boolean`	`decodeMemstoreTS`
`private HFile.FileInfo`	`fileInfo`
`private long`	`fileSize` Size of this file.
`private HFileBlock.FSReader`	`fsBlockReader` Filesystem-level block reader.
`private HFileContext`	`hfileContext`
`private boolean`	`includesMemstoreTS`
`static int`	`KEY_VALUE_LEN_SIZE` The size of a (key length, value length) tuple that prefixes each entry in a data block.
`private Cell`	`lastKeyCell` Last key in the file.
`private List<HFileBlock>`	`loadOnOpenBlocks` Blocks read from the load-on-open section, excluding data root index, meta index, and file info.
`private static org.slf4j.Logger`	`LOG`
`(package private) static int`	`MAX_MINOR_VERSION` Maximum minor version supported by this HFile format
`private HFileBlockIndex.ByteArrayKeyBlockIndexReader`	`metaBlockIndexReader` Meta block index reader -- always single level
`(package private) static int`	`MIN_MINOR_VERSION` Minimum minor version supported by this HFile format
`private static int`	`MIN_V2_MINOR_VERSION_WITH_PB` We can read files whose major version is v2 IFF their minor version is at least 3.
`static int`	`MINOR_VERSION_NO_CHECKSUM` In HFile minor version that does not support checksums
`static int`	`MINOR_VERSION_WITH_CHECKSUM` Minor versions in HFile starting with this number have hbase checksums
`(package private) static int`	`MINOR_VERSION_WITH_FAKED_KEY` Minor versions starting with this number have faked index key
`private String`	`name` File name to be used for block names
`private IdLock`	`offsetLock` A "sparse lock" implementation allowing to lock on a particular block identified by offset.
`private org.apache.hadoop.fs.Path`	`path` Path of file
`static int`	`PBUF_TRAILER_MINOR_VERSION` HFile minor version that introduced pbuf filetrailer
`private boolean`	`primaryReplicaReader`
`private FixedFileTrailer`	`trailer`

Constructor Summary

Constructors
Constructor and Description
`HFileReaderImpl(org.apache.hadoop.fs.Path path, FixedFileTrailer trailer, FSDataInputStreamWrapper fsdis, long fileSize, CacheConfig cacheConf, HFileSystem hfs, boolean primaryReplicaReader, org.apache.hadoop.conf.Configuration conf)` Opens a HFile.
`HFileReaderImpl(org.apache.hadoop.fs.Path path, FixedFileTrailer trailer, FSDataInputStreamWrapper fsdis, long fileSize, CacheConfig cacheConf, HFileSystem hfs, org.apache.hadoop.conf.Configuration conf)` Deprecated.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`private void`	`checkFileVersion()` File version check is a little sloppy.
`void`	`close()`
`void`	`close(boolean evictOnClose)` Close method with optional evictOnClose
`protected HFileContext`	`createHFileContext(FSDataInputStreamWrapper fsdis, long fileSize, HFileSystem hfs, org.apache.hadoop.fs.Path path, FixedFileTrailer trailer)`
`private DataInput`	`getBloomFilterMetadata(BlockType blockType)`
`private HFileBlock`	`getCachedBlock(BlockCacheKey cacheKey, boolean cacheBlock, boolean useLock, boolean isCompaction, boolean updateCacheMetrics, BlockType expectedBlockType, DataBlockEncoding expectedDataBlockEncoding)` Retrieve block from cache.
`CellComparator`	`getComparator()`
`Compression.Algorithm`	`getCompressionAlgorithm()`
`org.apache.hadoop.conf.Configuration`	`getConf()`
`DataBlockEncoding`	`getDataBlockEncoding()`
`HFileBlockIndex.BlockIndexReader`	`getDataBlockIndexReader()`
`DataInput`	`getDeleteBloomFilterMetadata()` Retrieves delete family Bloom filter metadata as appropriate for each `HFile` version.
`DataBlockEncoding`	`getEffectiveEncodingInCache(boolean isCompaction)`
`long`	`getEntries()`
`HFileContext`	`getFileContext()` Return the file context of the HFile this reader belongs to
`Optional<Cell>`	`getFirstKey()`
`Optional<byte[]>`	`getFirstRowKey()` TODO left from `HFile` version 1: move this to StoreFile after Ryan's patch goes in to eliminate `KeyValue` here.
`DataInput`	`getGeneralBloomFilterMetadata()` Returns a buffer with the Bloom filter metadata.
`Optional<Cell>`	`getLastKey()`
`Optional<byte[]>`	`getLastRowKey()` TODO left from `HFile` version 1: move this to StoreFile after Ryan's patch goes in to eliminate `KeyValue` here.
`int`	`getMajorVersion()`
`HFileBlock`	`getMetaBlock(String metaBlockName, boolean cacheBlock)`
`String`	`getName()` Returns this reader's "name".
`org.apache.hadoop.fs.Path`	`getPath()`
`private static String`	`getPathOffsetEndStr(org.apache.hadoop.fs.Path path, long offset, long end)`
`HFileScanner`	`getScanner(boolean cacheBlocks, boolean pread)` Create a Scanner on this file.
`HFileScanner`	`getScanner(boolean cacheBlocks, boolean pread, boolean isCompaction)` Create a Scanner on this file.
`FixedFileTrailer`	`getTrailer()`
`HFileBlock.FSReader`	`getUncachedBlockReader()` For testing
`boolean`	`hasMVCCInfo()`
`long`	`indexSize()`
`boolean`	`isDecodeMemStoreTS()`
`boolean`	`isFileInfoLoaded()`
`boolean`	`isPrimaryReplicaReader()`
`long`	`length()`
`HFile.FileInfo`	`loadFileInfo()`
`Optional<Cell>`	`midKey()`
`boolean`	`prefetchComplete()` Returns false if block prefetching was requested for this file and has not completed, true otherwise
`HFileBlock`	`readBlock(long dataBlockOffset, long onDiskBlockSize, boolean cacheBlock, boolean pread, boolean isCompaction, boolean updateCacheMetrics, BlockType expectedBlockType, DataBlockEncoding expectedDataBlockEncoding)` Read in a file block.
`void`	`returnBlock(HFileBlock block)` Return the given block back to the cache, if it was obtained from cache.
`void`	`setConf(org.apache.hadoop.conf.Configuration conf)`
`boolean`	`shouldIncludeMemStoreTS()`
`String`	`toString()`
`private Optional<String>`	`toStringFirstKey()`
`private Optional<String>`	`toStringLastKey()`
`void`	`unbufferStream()` To close the stream's socket.
`private void`	`validateBlockType(HFileBlock block, BlockType expectedBlockType)` Compares the actual type of a block retrieved from cache or disk with its expected type and throws an exception in case of a mismatch.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - LOG
```
private static final org.slf4j.Logger LOG
```
  - dataBlockIndexReader
```
private HFileBlockIndex.CellBasedKeyBlockIndexReader dataBlockIndexReader
```
    Data block index reader keeping the root data index in memory
  - metaBlockIndexReader
```
private HFileBlockIndex.ByteArrayKeyBlockIndexReader metaBlockIndexReader
```
    Meta block index reader -- always single level
  - trailer
```
private final FixedFileTrailer trailer
```
  - compressAlgo
```
private final Compression.Algorithm compressAlgo
```
    Filled when we read in the trailer.
  - primaryReplicaReader
```
private final boolean primaryReplicaReader
```
  - dataBlockEncoder
```
private HFileDataBlockEncoder dataBlockEncoder
```
    What kind of data block encoding should be used while reading, writing, and handling cache.
  - lastKeyCell
```
private Cell lastKeyCell
```
    Last key in the file. Filled in when we read in the file info
  - avgKeyLen
```
private int avgKeyLen
```
    Average key length read from file info
  - avgValueLen
```
private int avgValueLen
```
    Average value length read from file info
  - comparator
```
private CellComparator comparator
```
    Key comparator
  - fileSize
```
private final long fileSize
```
    Size of this file.
  - cacheConf
```
private final CacheConfig cacheConf
```
    Block cache configuration.
  - path
```
private final org.apache.hadoop.fs.Path path
```
    Path of file
  - name
```
private final String name
```
    File name to be used for block names
  - fileInfo
```
private HFile.FileInfo fileInfo
```
  - conf
```
private org.apache.hadoop.conf.Configuration conf
```
  - hfileContext
```
private HFileContext hfileContext
```
  - fsBlockReader
```
private HFileBlock.FSReader fsBlockReader
```
    Filesystem-level block reader.
  - offsetLock
```
private IdLock offsetLock
```
    A "sparse lock" implementation allowing to lock on a particular block identified by offset. The purpose of this is to avoid two clients loading the same block, and have all but one client wait to get the block from the cache.
  - loadOnOpenBlocks
```
private List<HFileBlock> loadOnOpenBlocks
```
    Blocks read from the load-on-open section, excluding data root index, meta index, and file info.
  - MIN_MINOR_VERSION
```
static final int MIN_MINOR_VERSION
```
    Minimum minor version supported by this HFile format
    
    See Also:
    
    Constant Field Values
  - MAX_MINOR_VERSION
```
static final int MAX_MINOR_VERSION
```
    Maximum minor version supported by this HFile format
    
    See Also:
    
    Constant Field Values
  - MIN_V2_MINOR_VERSION_WITH_PB
```
private static final int MIN_V2_MINOR_VERSION_WITH_PB
```
    We can read files whose major version is v2 IFF their minor version is at least 3.
    
    See Also:
    
    Constant Field Values
  - MINOR_VERSION_WITH_FAKED_KEY
```
static final int MINOR_VERSION_WITH_FAKED_KEY
```
    Minor versions starting with this number have faked index key
    
    See Also:
    
    Constant Field Values
  - MINOR_VERSION_WITH_CHECKSUM
```
public static final int MINOR_VERSION_WITH_CHECKSUM
```
    Minor versions in HFile starting with this number have hbase checksums
    
    See Also:
    
    Constant Field Values
  - MINOR_VERSION_NO_CHECKSUM
```
public static final int MINOR_VERSION_NO_CHECKSUM
```
    In HFile minor version that does not support checksums
    
    See Also:
    
    Constant Field Values
  - PBUF_TRAILER_MINOR_VERSION
```
public static final int PBUF_TRAILER_MINOR_VERSION
```
    HFile minor version that introduced pbuf filetrailer
    
    See Also:
    
    Constant Field Values
  - KEY_VALUE_LEN_SIZE
```
public static final int KEY_VALUE_LEN_SIZE
```
    The size of a (key length, value length) tuple that prefixes each entry in a data block.
    
    See Also:
    
    Constant Field Values
  - includesMemstoreTS
```
private boolean includesMemstoreTS
```
  - decodeMemstoreTS
```
protected boolean decodeMemstoreTS
```
- Constructor Detail
  - HFileReaderImpl
```
@Deprecated
public HFileReaderImpl(org.apache.hadoop.fs.Path path,
                                   FixedFileTrailer trailer,
                                   FSDataInputStreamWrapper fsdis,
                                   long fileSize,
                                   CacheConfig cacheConf,
                                   HFileSystem hfs,
                                   org.apache.hadoop.conf.Configuration conf)
                            throws IOException
```
    Deprecated.
    
    Throws:
    
    IOException
  - HFileReaderImpl
```
public HFileReaderImpl(org.apache.hadoop.fs.Path path,
                       FixedFileTrailer trailer,
                       FSDataInputStreamWrapper fsdis,
                       long fileSize,
                       CacheConfig cacheConf,
                       HFileSystem hfs,
                       boolean primaryReplicaReader,
                       org.apache.hadoop.conf.Configuration conf)
                throws IOException
```
    Opens a HFile. You must load the index before you can use it by calling loadFileInfo().
    
    Parameters:
    
    path - Path to HFile.
    
    trailer - File trailer.
    
    fsdis - input stream.
    
    fileSize - Length of the stream.
    
    cacheConf - Cache configuration.
    
    hfs - The file system.
    
    conf - Configuration
    
    Throws:
    
    IOException
- Method Detail
  - getPathOffsetEndStr
```
private static String getPathOffsetEndStr(org.apache.hadoop.fs.Path path,
                                          long offset,
                                          long end)
```
  - checkFileVersion
```
private void checkFileVersion()
```
    File version check is a little sloppy. We read v3 files but can also read v2 files if their content has been pb'd; files written with 0.98.
  - toStringFirstKey
```
private Optional<String> toStringFirstKey()
```
  - toStringLastKey
```
private Optional<String> toStringLastKey()
```
  - toString
```
public String toString()
```
    Overrides:
    
    toString in class Object
  - length
```
public long length()
```
    Specified by:
    
    length in interface HFile.Reader
  - returnBlock
```
public void returnBlock(HFileBlock block)
```
    Description copied from interface: HFile.CachingBlockReader
    
    Return the given block back to the cache, if it was obtained from cache.
    
    Specified by:
    
    returnBlock in interface HFile.CachingBlockReader
    
    Parameters:
    
    block - Block to be returned.
  - getFirstKey
```
public Optional<Cell> getFirstKey()
```
    Specified by:
    
    getFirstKey in interface HFile.Reader
    
    Returns:
    
    the first key in the file. May be null if file has no entries. Note that this is not the first row key, but rather the byte form of the first KeyValue.
  - getFirstRowKey
```
public Optional<byte[]> getFirstRowKey()
```
    TODO left from HFile version 1: move this to StoreFile after Ryan's patch goes in to eliminate KeyValue here.
    
    Specified by:
    
    getFirstRowKey in interface HFile.Reader
    
    Returns:
    
    the first row key, or null if the file is empty.
  - getLastRowKey
```
public Optional<byte[]> getLastRowKey()
```
    TODO left from HFile version 1: move this to StoreFile after Ryan's patch goes in to eliminate KeyValue here.
    
    Specified by:
    
    getLastRowKey in interface HFile.Reader
    
    Returns:
    
    the last row key, or null if the file is empty.
  - getEntries
```
public long getEntries()
```
    Specified by:
    
    getEntries in interface HFile.Reader
    
    Returns:
    
    number of KV entries in this HFile
  - getComparator
```
public CellComparator getComparator()
```
    Specified by:
    
    getComparator in interface HFile.Reader
    
    Returns:
    
    comparator
  - getCompressionAlgorithm
```
public Compression.Algorithm getCompressionAlgorithm()
```
    Specified by:
    
    getCompressionAlgorithm in interface HFile.Reader
    
    Returns:
    
    compression algorithm
  - indexSize
```
public long indexSize()
```
    Specified by:
    
    indexSize in interface HFile.Reader
    
    Returns:
    
    the total heap size of data and meta block indexes in bytes. Does not take into account non-root blocks of a multilevel data index.
  - getName
```
public String getName()
```
    Description copied from interface: HFile.Reader
    
    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.
    
    Specified by:
    
    getName in interface HFile.Reader
  - getDataBlockIndexReader
```
public HFileBlockIndex.BlockIndexReader getDataBlockIndexReader()
```
    Specified by:
    
    getDataBlockIndexReader in interface HFile.Reader
  - getTrailer
```
public FixedFileTrailer getTrailer()
```
    Specified by:
    
    getTrailer in interface HFile.Reader
  - isPrimaryReplicaReader
```
public boolean isPrimaryReplicaReader()
```
    Specified by:
    
    isPrimaryReplicaReader in interface HFile.Reader
  - loadFileInfo
```
public HFile.FileInfo loadFileInfo()
                            throws IOException
```
    Specified by:
    
    loadFileInfo in interface HFile.Reader
    
    Throws:
    
    IOException
  - getPath
```
public org.apache.hadoop.fs.Path getPath()
```
    Specified by:
    
    getPath in interface HFile.Reader
  - getDataBlockEncoding
```
public DataBlockEncoding getDataBlockEncoding()
```
    Specified by:
    
    getDataBlockEncoding in interface HFile.Reader
  - getConf
```
public org.apache.hadoop.conf.Configuration getConf()
```
    Specified by:
    
    getConf in interface org.apache.hadoop.conf.Configurable
  - setConf
```
public void setConf(org.apache.hadoop.conf.Configuration conf)
```
    Specified by:
    
    setConf in interface org.apache.hadoop.conf.Configurable
  - isDecodeMemStoreTS
```
public boolean isDecodeMemStoreTS()
```
    Specified by:
    
    isDecodeMemStoreTS in interface HFile.Reader
  - shouldIncludeMemStoreTS
```
public boolean shouldIncludeMemStoreTS()
```
    Specified by:
    
    shouldIncludeMemStoreTS in interface HFile.Reader
  - getCachedBlock
```
private HFileBlock getCachedBlock(BlockCacheKey cacheKey,
                                  boolean cacheBlock,
                                  boolean useLock,
                                  boolean isCompaction,
                                  boolean updateCacheMetrics,
                                  BlockType expectedBlockType,
                                  DataBlockEncoding expectedDataBlockEncoding)
                           throws IOException
```
    Retrieve block from cache. Validates the retrieved block's type vs expectedBlockType and its encoding vs. expectedDataBlockEncoding. Unpacks the block as necessary.
    
    Throws:
    
    IOException
  - getMetaBlock
```
public HFileBlock getMetaBlock(String metaBlockName,
                               boolean cacheBlock)
                        throws IOException
```
    Specified by:
    
    getMetaBlock in interface HFile.Reader
    
    Parameters:
    
    metaBlockName -
    
    cacheBlock - Add block to cache, if found
    
    Returns:
    
    block wrapped in a ByteBuffer, with header skipped
    
    Throws:
    
    IOException
  - readBlock
```
public HFileBlock readBlock(long dataBlockOffset,
                            long onDiskBlockSize,
                            boolean cacheBlock,
                            boolean pread,
                            boolean isCompaction,
                            boolean updateCacheMetrics,
                            BlockType expectedBlockType,
                            DataBlockEncoding expectedDataBlockEncoding)
                     throws IOException
```
    Description copied from interface: HFile.CachingBlockReader
    
    Read in a file block.
    
    Specified by:
    
    readBlock in interface HFile.CachingBlockReader
    
    Parameters:
    
    dataBlockOffset - offset to read.
    
    onDiskBlockSize - size of the block
    
    isCompaction - is this block being read as part of a compaction
    
    expectedBlockType - the block type we are expecting to read with this read operation, or null to read whatever block type is available and avoid checking (that might reduce caching efficiency of encoded data blocks)
    
    expectedDataBlockEncoding - the data block encoding the caller is expecting data blocks to be in, or null to not perform this check and return the block irrespective of the encoding. This check only applies to data blocks and can be set to null when the caller is expecting to read a non-data block and has set expectedBlockType accordingly.
    
    Returns:
    
    Block wrapped in a ByteBuffer.
    
    Throws:
    
    IOException
  - hasMVCCInfo
```
public boolean hasMVCCInfo()
```
    Specified by:
    
    hasMVCCInfo in interface HFile.Reader
  - validateBlockType
```
private void validateBlockType(HFileBlock block,
                               BlockType expectedBlockType)
                        throws IOException
```
    Compares the actual type of a block retrieved from cache or disk with its expected type and throws an exception in case of a mismatch. Expected block type of BlockType.DATA is considered to match the actual block type [@link BlockType.ENCODED_DATA as well.
    
    Parameters:
    
    block - a block retrieved from cache or disk
    
    expectedBlockType - the expected block type, or null to skip the check
    
    Throws:
    
    IOException
  - getLastKey
```
public Optional<Cell> getLastKey()
```
    Specified by:
    
    getLastKey in interface HFile.Reader
    
    Returns:
    
    Last key as cell in the file. May be null if file has no entries. Note that this is not the last row key, but it is the Cell representation of the last key
  - midKey
```
public Optional<Cell> midKey()
                      throws IOException
```
    Specified by:
    
    midKey in interface HFile.Reader
    
    Returns:
    
    Midkey for this file. We work with block boundaries only so returned midkey is an approximation only.
    
    Throws:
    
    IOException
  - close
```
public void close()
           throws IOException
```
    Specified by:
    
    close in interface Closeable
    
    Specified by:
    
    close in interface AutoCloseable
    
    Throws:
    
    IOException
  - close
```
public void close(boolean evictOnClose)
           throws IOException
```
    Description copied from interface: HFile.Reader
    
    Close method with optional evictOnClose
    
    Specified by:
    
    close in interface HFile.Reader
    
    Throws:
    
    IOException
  - getEffectiveEncodingInCache
```
public DataBlockEncoding getEffectiveEncodingInCache(boolean isCompaction)
```
    Specified by:
    
    getEffectiveEncodingInCache in interface HFile.Reader
  - getUncachedBlockReader
```
public HFileBlock.FSReader getUncachedBlockReader()
```
    For testing
    
    Specified by:
    
    getUncachedBlockReader in interface HFile.Reader
  - getGeneralBloomFilterMetadata
```
public DataInput getGeneralBloomFilterMetadata()
                                        throws IOException
```
    Returns a buffer with the Bloom filter metadata. The caller takes ownership of the buffer.
    
    Specified by:
    
    getGeneralBloomFilterMetadata in interface HFile.Reader
    
    Throws:
    
    IOException
  - getDeleteBloomFilterMetadata
```
public DataInput getDeleteBloomFilterMetadata()
                                       throws IOException
```
    Description copied from interface: HFile.Reader
    
    Retrieves delete family Bloom filter metadata as appropriate for each HFile version. Knows nothing about how that metadata is structured.
    
    Specified by:
    
    getDeleteBloomFilterMetadata in interface HFile.Reader
    
    Throws:
    
    IOException
  - getBloomFilterMetadata
```
private DataInput getBloomFilterMetadata(BlockType blockType)
                                  throws IOException
```
    Throws:
    
    IOException
  - isFileInfoLoaded
```
public boolean isFileInfoLoaded()
```
  - getFileContext
```
public HFileContext getFileContext()
```
    Description copied from interface: HFile.Reader
    
    Return the file context of the HFile this reader belongs to
    
    Specified by:
    
    getFileContext in interface HFile.Reader
  - prefetchComplete
```
public boolean prefetchComplete()
```
    Returns false if block prefetching was requested for this file and has not completed, true otherwise
    
    Specified by:
    
    prefetchComplete in interface HFile.Reader
  - createHFileContext
```
protected HFileContext createHFileContext(FSDataInputStreamWrapper fsdis,
                                          long fileSize,
                                          HFileSystem hfs,
                                          org.apache.hadoop.fs.Path path,
                                          FixedFileTrailer trailer)
                                   throws IOException
```
    Throws:
    
    IOException
  - getScanner
```
public HFileScanner getScanner(boolean cacheBlocks,
                               boolean pread)
```
    Create a Scanner on this file. No seeks or reads are done on creation. Call HFileScanner.seekTo(Cell) to position an start the read. There is nothing to clean up in a Scanner. Letting go of your references to the scanner is sufficient. NOTE: Do not use this overload of getScanner for compactions. See getScanner(boolean, boolean, boolean)
    
    Specified by:
    
    getScanner in interface HFile.Reader
    
    Parameters:
    
    cacheBlocks - True if we should cache blocks read in by this scanner.
    
    pread - Use positional read rather than seek+read if true (pread is better for random reads, seek+read is better scanning).
    
    Returns:
    
    Scanner on this file.
  - getScanner
```
public HFileScanner getScanner(boolean cacheBlocks,
                               boolean pread,
                               boolean isCompaction)
```
    Create a Scanner on this file. No seeks or reads are done on creation. Call HFileScanner.seekTo(Cell) to position an start the read. There is nothing to clean up in a Scanner. Letting go of your references to the scanner is sufficient.
    
    Specified by:
    
    getScanner in interface HFile.Reader
    
    Parameters:
    
    cacheBlocks - True if we should cache blocks read in by this scanner.
    
    pread - Use positional read rather than seek+read if true (pread is better for random reads, seek+read is better scanning).
    
    isCompaction - is scanner being used for a compaction?
    
    Returns:
    
    Scanner on this file.
  - getMajorVersion
```
public int getMajorVersion()
```
  - unbufferStream
```
public void unbufferStream()
```
    Description copied from interface: HFile.Reader
    
    To close the stream's socket. Note: This can be concurrently called from multiple threads and implementation should take care of thread safety.
    
    Specified by:
    
    unbufferStream in interface HFile.Reader

Class HFileReaderImpl

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

LOG

dataBlockIndexReader

metaBlockIndexReader

trailer

compressAlgo

primaryReplicaReader

dataBlockEncoder

lastKeyCell

avgKeyLen

avgValueLen

comparator

fileSize

cacheConf

path

name

fileInfo

conf

hfileContext

fsBlockReader

offsetLock

loadOnOpenBlocks

MIN_MINOR_VERSION

MAX_MINOR_VERSION

MIN_V2_MINOR_VERSION_WITH_PB

MINOR_VERSION_WITH_FAKED_KEY

MINOR_VERSION_WITH_CHECKSUM

MINOR_VERSION_NO_CHECKSUM

PBUF_TRAILER_MINOR_VERSION

KEY_VALUE_LEN_SIZE

includesMemstoreTS

decodeMemstoreTS

Constructor Detail

HFileReaderImpl

HFileReaderImpl

Method Detail

getPathOffsetEndStr

checkFileVersion

toStringFirstKey

toStringLastKey

toString

length

returnBlock

getFirstKey

getFirstRowKey

getLastRowKey

getEntries

getComparator

getCompressionAlgorithm

indexSize

getName

getDataBlockIndexReader

getTrailer

isPrimaryReplicaReader

loadFileInfo

getPath

getDataBlockEncoding

getConf

setConf

isDecodeMemStoreTS

shouldIncludeMemStoreTS

getCachedBlock

getMetaBlock

readBlock

hasMVCCInfo

validateBlockType

getLastKey

midKey

close

close

getEffectiveEncodingInCache

getUncachedBlockReader

getGeneralBloomFilterMetadata

getDeleteBloomFilterMetadata