org.apache.hadoop.hbase.io.hfile

Class TestHFileBlockCompatibility.Writer

java.lang.Object

org.apache.hadoop.hbase.io.hfile.HFileBlock.Writer

org.apache.hadoop.hbase.io.hfile.TestHFileBlockCompatibility.Writer

Enclosing class:

TestHFileBlockCompatibility

public static final class TestHFileBlockCompatibility.Writer
extends HFileBlock.Writer

This is the version of the HFileBlock.Writer that is used to create V2 blocks with minor version 0. These blocks do not have hbase-level checksums. The code is here to test backward compatibility. The reason we do not inherit from HFileBlock.Writer is because we never ever want to change the code in this class but the code in HFileBlock.Writer will continually evolve.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hbase.io.hfile.HFileBlock.Writer

HFileBlock.Writer.BufferGrabbingByteArrayOutputStream

Constructor Summary

Constructors

Constructor and Description
Writer(Compression.Algorithm compressionAlgorithm, HFileDataBlockEncoder dataBlockEncoder, boolean includesMemstoreTS, boolean includesTag)
Writer(HFileDataBlockEncoder dataBlockEncoder, HFileContext meta)

Method Summary

Modifier and Type	Method and Description
int	blockSizeWritten() Returns the number of bytes written into the current block so far, or zero if not writing the block at the moment.
HFileBlock	getBlockForCaching() Creates a new HFileBlock.
byte[]	getHeaderAndData() Returns the header or the compressed data (or uncompressed data when not using compression) as a byte array.
int	getOnDiskSizeWithHeader() Returns the on-disk size of the block.
int	getOnDiskSizeWithoutHeader() Returns the on-disk size of the data portion of the block.
java.nio.ByteBuffer	getUncompressedBufferWithHeader() Similar to getUncompressedBufferWithHeader() but returns a byte buffer.
int	getUncompressedSizeWithHeader() The uncompressed size of the block data, including header size.
int	getUncompressedSizeWithoutHeader() The uncompressed size of the block data.
boolean	isWriting()
void	releaseCompressor() Releases the compressor this writer uses to compress blocks into the compressor pool.
java.io.DataOutputStream	startWriting(BlockType newBlockType) Starts writing into the block.
void	write(Cell c) Writes the Cell to this block
void	writeBlock(HFileBlock.BlockWritable bw, FSDataOutputStream out) Takes the given HFileBlock.BlockWritable instance, creates a new block of its appropriate type, writes the writable into this block, and flushes the block into the output stream.
void	writeHeaderAndData(FSDataOutputStream out) Similar to writeHeaderAndData(FSDataOutputStream), but records the offset of this block so that it can be referenced in the next block of the same type.

Methods inherited from class org.apache.hadoop.hbase.io.hfile.HFileBlock.Writer

finishBlockAndWriteHeaderAndData, getBlockForCaching, release

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Writer

public Writer(Compression.Algorithm compressionAlgorithm,
              HFileDataBlockEncoder dataBlockEncoder,
              boolean includesMemstoreTS,
              boolean includesTag)

Writer

public Writer(HFileDataBlockEncoder dataBlockEncoder,
              HFileContext meta)

Method Detail

startWriting

public java.io.DataOutputStream startWriting(BlockType newBlockType)
                                      throws java.io.IOException

Starts writing into the block. The previous block's data is discarded.

Overrides:

startWriting in class HFileBlock.Writer

Returns:

the stream the user can write their data into

Throws:

java.io.IOException

write

public void write(Cell c)
           throws java.io.IOException

Description copied from class: HFileBlock.Writer

Writes the Cell to this block

Overrides:

write in class HFileBlock.Writer

Throws:

java.io.IOException

writeHeaderAndData

public void writeHeaderAndData(FSDataOutputStream out)
                        throws java.io.IOException

Similar to writeHeaderAndData(FSDataOutputStream), but records the offset of this block so that it can be referenced in the next block of the same type.

Overrides:

writeHeaderAndData in class HFileBlock.Writer

Parameters:

out -

Throws:

java.io.IOException

getHeaderAndData

public byte[] getHeaderAndData()
                        throws java.io.IOException

Returns the header or the compressed data (or uncompressed data when not using compression) as a byte array. Can be called in the "writing" state or in the "block ready" state. If called in the "writing" state, transitions the writer to the "block ready" state.

Returns:

header and data as they would be stored on disk in a byte array

Throws:

java.io.IOException

releaseCompressor

public void releaseCompressor()

Releases the compressor this writer uses to compress blocks into the compressor pool. Needs to be called before the writer is discarded.

getOnDiskSizeWithoutHeader

public int getOnDiskSizeWithoutHeader()

Returns the on-disk size of the data portion of the block. This is the compressed size if compression is enabled. Can only be called in the "block ready" state. Header is not compressed, and its size is not included in the return value.

Returns:

the on-disk size of the block, not including the header.

getOnDiskSizeWithHeader

public int getOnDiskSizeWithHeader()

Returns the on-disk size of the block. Can only be called in the "block ready" state.

Returns:

the on-disk size of the block ready to be written, including the header size

getUncompressedSizeWithoutHeader

public int getUncompressedSizeWithoutHeader()

The uncompressed size of the block data. Does not include header size.

getUncompressedSizeWithHeader

public int getUncompressedSizeWithHeader()

The uncompressed size of the block data, including header size.

isWriting

public boolean isWriting()

Overrides:

isWriting in class HFileBlock.Writer

Returns:

true if a block is being written

blockSizeWritten

public int blockSizeWritten()

Returns the number of bytes written into the current block so far, or zero if not writing the block at the moment. Note that this will return zero in the "block ready" state as well.

Overrides:

blockSizeWritten in class HFileBlock.Writer

Returns:

the number of bytes written

getUncompressedBufferWithHeader

public java.nio.ByteBuffer getUncompressedBufferWithHeader()

Similar to getUncompressedBufferWithHeader() but returns a byte buffer.

Returns:

uncompressed block for caching on write in the form of a buffer

writeBlock

public void writeBlock(HFileBlock.BlockWritable bw,
                       FSDataOutputStream out)
                throws java.io.IOException

Takes the given HFileBlock.BlockWritable instance, creates a new block of its appropriate type, writes the writable into this block, and flushes the block into the output stream. The writer is instructed not to buffer uncompressed bytes for cache-on-write.

Overrides:

writeBlock in class HFileBlock.Writer

Parameters:

bw - the block-writable object to write as a block

out - the file system output stream

Throws:

java.io.IOException

getBlockForCaching

public HFileBlock getBlockForCaching()

Creates a new HFileBlock.