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

Class ExclusiveMemHFileBlock

java.lang.Object

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

org.apache.hadoop.hbase.io.hfile.ExclusiveMemHFileBlock

All Implemented Interfaces:

HeapSize, Cacheable, HBaseReferenceCounted, org.apache.hbase.thirdparty.io.netty.util.ReferenceCounted

@Private
public class ExclusiveMemHFileBlock
extends HFileBlock

The ByteBuffAllocator won't allocate pooled heap ByteBuff now; at the same time, if allocate an off-heap ByteBuff from allocator, then it must be a pooled one. That's to say, an exclusive memory HFileBlock would must be an heap block and a shared memory HFileBlock would must be an off-heap block.

The exclusive memory HFileBlock will do nothing when calling retain or release methods, because its memory will be garbage collected by JVM, even if its reference count decrease to zero, we can do nothing for the de-allocating.

See Also:

• SharedMemHFileBlock

Nested Class Summary

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

HFileBlock.BlockDeserializer, HFileBlock.BlockIterator, HFileBlock.BlockWritable, HFileBlock.FSReader, HFileBlock.FSReaderImpl, HFileBlock.Header, HFileBlock.Writer

Field Summary

Fields inherited from class org.apache.hadoop.hbase.io.hfile.HFileBlock

BLOCK_DESERIALIZER, BLOCK_METADATA_SPACE, CHECKSUM_SIZE, CHECKSUM_VERIFICATION_NUM_IO_THRESHOLD, DONT_FILL_HEADER, DUMMY_HEADER_NO_CHECKSUM, FILL_HEADER, FIXED_OVERHEAD, MULTI_BYTE_BUFFER_HEAP_SIZE

Constructor Summary

Constructors

Constructor	Description
ExclusiveMemHFileBlock(BlockType blockType, int onDiskSizeWithoutHeader, int uncompressedSizeWithoutHeader, long prevBlockOffset, ByteBuff buf, boolean fillHeader, long offset, int nextBlockOnDiskSize, int onDiskDataSizeWithHeader, HFileContext fileContext, ByteBuffAllocator alloc)

Method Summary

Modifier and Type	Method	Description
boolean	isSharedMem()	Will be override by SharedMemHFileBlock or ExclusiveMemHFileBlock.
int	refCnt()	Reference count of this Cacheable.
boolean	release()	Call ByteBuff.release() to decrease the reference count, if no other reference, it will return back the ByteBuffer to ByteBuffAllocator
ExclusiveMemHFileBlock	retain()	Increase its reference count, and only when no reference we can free the object's memory.

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

createFromBuff, deepCloneOnHeap, equals, getBlockType, getBufferReadOnly, getBufferWithoutHeader, getByteBuffAllocator, getBytesPerChecksum, getByteStream, getChecksumType, getDataBlockEncoding, getDataBlockEncodingId, getDeserializer, getDummyHeaderForVersion, getHFileContext, getMetaData, getNextBlockOnDiskSize, getOffset, getOnDiskDataSizeWithHeader, getOnDiskSizeWithHeader, getOnDiskSizeWithoutHeader, getPrevBlockOffset, getSerializedLength, getUncompressedSizeWithoutHeader, hashCode, headerSize, headerSize, heapSize, isUnpacked, sanityCheck, sanityCheckUncompressed, serialize, toString, toStringHeader, totalChecksumBytes, touch, touch, unpack

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.hadoop.hbase.nio.HBaseReferenceCounted

release, retain

Constructor Details

ExclusiveMemHFileBlock

ExclusiveMemHFileBlock(BlockType blockType,
 int onDiskSizeWithoutHeader,
 int uncompressedSizeWithoutHeader,
 long prevBlockOffset,
 ByteBuff buf,
 boolean fillHeader,
 long offset,
 int nextBlockOnDiskSize,
 int onDiskDataSizeWithHeader,
 HFileContext fileContext,
 ByteBuffAllocator alloc)

Method Details

refCnt

public int refCnt()

Description copied from interface: Cacheable

Reference count of this Cacheable.

Specified by:

refCnt in interface Cacheable

Specified by:

refCnt in interface org.apache.hbase.thirdparty.io.netty.util.ReferenceCounted

Overrides:

refCnt in class HFileBlock

retain

public ExclusiveMemHFileBlock retain()

Description copied from interface: Cacheable

Increase its reference count, and only when no reference we can free the object's memory.

Specified by:

retain in interface Cacheable

Specified by:

retain in interface org.apache.hbase.thirdparty.io.netty.util.ReferenceCounted

Overrides:

retain in class HFileBlock

release

public boolean release()

Description copied from class: HFileBlock

Call ByteBuff.release() to decrease the reference count, if no other reference, it will return back the ByteBuffer to ByteBuffAllocator

Specified by:

release in interface Cacheable

Specified by:

release in interface org.apache.hbase.thirdparty.io.netty.util.ReferenceCounted

Overrides:

release in class HFileBlock

isSharedMem

public boolean isSharedMem()

Description copied from class: HFileBlock

Will be override by SharedMemHFileBlock or ExclusiveMemHFileBlock. Return true by default.

Overrides:

isSharedMem in class HFileBlock