• Interface Summary 

  Interface	Description
  BlockCache	Block cache interface.
  Cacheable	Cacheable is an interface that allows for an object to be cached.
  CacheableDeserializer<T extends Cacheable>	Interface for a deserializer.
  CachedBlock
  HFile.CachingBlockReader	An abstraction used by the block index.
  HFile.Reader	An interface used by clients to open and iterate an HFile.
  HFile.Writer	API required to write an HFile
  HFileBlock.BlockIterator	An interface allowing to iterate HFileBlocks.
  HFileBlock.BlockWritable	Something that can be written into a block.
  HFileBlock.FSReader	A full-fledged reader with iteration ability.
  HFileDataBlockEncoder	Controls what kind of data block encoding is used.
  HFileScanner	A scanner allows you to position yourself within a HFile and scan through it.
  InlineBlockWriter	A way to write "inline" blocks into an HFile.
  ResizableBlockCache	BlockCache which is resizable.

• Class Summary 

  Class	Description
  AbstractHFileReader	Common functionality needed by all versions of HFile readers.
  AbstractHFileReader.Scanner
  AbstractHFileWriter	Common functionality needed by all versions of HFile writers.
  AgeSnapshot	Snapshot of block cache age in cache.
  BlockCacheKey	Cache Key for use with implementations of BlockCache
  BlockCachesIterator	Iterator over an array of BlockCache CachedBlocks.
  BlockCacheUtil	Utilty for aggregating counts in CachedBlocks and toString/toJSON CachedBlocks and BlockCaches.
  BlockCacheUtil.CachedBlockCountsPerFile	Little data structure to hold counts for a file.
  BlockCacheUtil.CachedBlocksByFile	Use one of these to keep a running account of cached blocks by file.
  BlockWithScanInfo	BlockWithScanInfo is wrapper class for HFileBlock with other attributes.
  CacheableDeserializerIdManager	This class is used to manage the identifiers for CacheableDeserializer
  CacheConfig	Stores all of the cache objects and configuration for a single HFile.
  CacheStats	Class that implements cache metrics.
  ChecksumUtil	Utility methods to compute and validate checksums.
  CombinedBlockCache	CombinedBlockCache is an abstraction layer that combines LruBlockCache and BucketCache.
  CombinedBlockCache.CombinedCacheStats
  FixedFileTrailer	The HFile has a fixed trailer which contains offsets to other variable parts of the file.
  HFile	File format for hbase.
  HFile.FileInfo	Metadata for this file.
  HFile.WriterFactory	This variety of ways to construct writers is used throughout the code, and we want to be able to swap writer implementations.
  HFileBlock	Reading HFile version 1 and 2 blocks, and writing version 2 blocks.
  HFileBlock.AbstractFSReader	A common implementation of some methods of HFileBlock.FSReader and some tools for implementing HFile format version-specific block readers.
  HFileBlock.FSReaderImpl	Reads version 2 blocks from the filesystem.
  HFileBlock.Header
  HFileBlock.PrefetchedHeader	We always prefetch the header of the next block, so that we know its on-disk size in advance and can read it in one operation.
  HFileBlock.Writer	Unified version 2 HFile block writer.
  HFileBlock.Writer.BufferGrabbingByteArrayOutputStream
  HFileBlockIndex	Provides functionality to write (HFileBlockIndex.BlockIndexWriter) and read BlockIndexReader single-level and multi-level block indexes.
  HFileBlockIndex.BlockIndexChunk	A single chunk of the block index in the process of writing.
  HFileBlockIndex.BlockIndexReader	The reader will always hold the root level index in the memory.
  HFileBlockIndex.BlockIndexWriter	Writes the block index into the output stream.
  HFileContext	This carries the information on some of the meta data about the HFile.
  HFileContextBuilder	A builder that helps in building up the HFileContext
  HFileDataBlockEncoderImpl	Do different kinds of data block encoding according to column family options.
  HFilePrettyPrinter	Implements pretty-printing functionality for HFiles.
  HFilePrettyPrinter.KeyValueStatsCollector
  HFilePrettyPrinter.SimpleReporter
  HFileReaderV2	HFile reader for version 2.
  HFileReaderV2.AbstractScannerV2
  HFileReaderV2.EncodedScannerV2	ScannerV2 that operates on encoded data blocks.
  HFileReaderV2.ScannerV2	Implementation of HFileScanner interface.
  HFileReaderV3	HFile reader for version 3.
  HFileReaderV3.EncodedScannerV3	ScannerV3 that operates on encoded data blocks.
  HFileReaderV3.ScannerV3	Implementation of HFileScanner interface.
  HFileUtil
  HFileWriterV2	Writes HFile format version 2.
  HFileWriterV2.WriterFactoryV2
  HFileWriterV3	HFile writer for version 3.
  HFileWriterV3.WriterFactoryV3
  InclusiveCombinedBlockCache
  LruBlockCache	A block cache implementation that is memory-aware using HeapSize, memory-bound using an LRU eviction algorithm, and concurrent: backed by a ConcurrentHashMap and with a non-blocking eviction thread giving constant-time LruBlockCache.cacheBlock(org.apache.hadoop.hbase.io.hfile.BlockCacheKey, org.apache.hadoop.hbase.io.hfile.Cacheable, boolean, boolean) and LruBlockCache.getBlock(org.apache.hadoop.hbase.io.hfile.BlockCacheKey, boolean, boolean, boolean) operations.
  LruBlockCache.EvictionThread
  LruBlockCache.StatisticsThread
  LruCachedBlock	Represents an entry in the LruBlockCache.
  LruCachedBlockQueue	A memory-bound queue that will grow until an element brings total size >= maxSize.
  MemcachedBlockCache	Class to store blocks into memcached.
  MemcachedBlockCache.HFileBlockTranscoder	Class to encode and decode an HFileBlock to and from memecached's resulting byte arrays.
  NoOpDataBlockEncoder	Does not perform any kind of encoding/decoding.
  PrefetchExecutor

• Enum Summary 

  Enum	Description
  BlockPriority
  BlockType	Various types of HFile blocks.
  BlockType.BlockCategory
  CacheConfig.ExternalBlockCaches	Enum of all built in external block caches.
  HFileBlock.Writer.State

• Exception Summary 

  Exception	Description
  AbstractHFileReader.BlockIndexNotLoadedException
  AbstractHFileReader.NotSeekedException	An exception thrown when an operation requiring a scanner to be seeked is invoked on a scanner that is not seeked.
  CorruptHFileException	This exception is thrown when attempts to read an HFile fail due to corruption or truncation issues.
  InvalidHFileException	Thrown when an invalid HFile format is detected

Package org.apache.hadoop.hbase.io.hfile Description