Package org.apache.flink.table.runtime.util

Class ResettableExternalBuffer

java.lang.Object

org.apache.flink.table.runtime.util.ResettableExternalBuffer

All Implemented Interfaces:

Closeable, AutoCloseable, ResettableRowBuffer

public class ResettableExternalBuffer
extends Object
implements ResettableRowBuffer

A resettable external buffer for binary row. It stores records in memory and spill to disk when memory is not enough. When the spill is completed, the records are written to memory again. The returned iterator reads the data in write order (read spilled records first). It supports infinite length. It can open multiple Iterators. It support new iterator with beginRow.

NOTE: Not supports reading while writing. In the face of concurrent modification, the iterator fails quickly and cleanly, rather than risking arbitrary, non-deterministic behavior at an undetermined time in the future.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
class	ResettableExternalBuffer.BufferIterator	Iterator of external buffer.

Nested classes/interfaces inherited from interface org.apache.flink.table.runtime.util.ResettableRowBuffer

ResettableRowBuffer.ResettableIterator

Field Summary

Fields

Modifier and Type	Field	Description
static final int	MIN_NUM_MEMORY	The minimum number of segments that are required, 320 KibiBytes.

Constructor Summary

Constructors

Constructor	Description
ResettableExternalBuffer(org.apache.flink.runtime.io.disk.iomanager.IOManager ioManager, LazyMemorySegmentPool pool, AbstractRowDataSerializer serializer, boolean isRowAllInFixedPart)

Method Summary

Modifier and Type	Method	Description
void	add(org.apache.flink.table.data.RowData row)	Appends the specified row to the end of this buffer.
void	close()	Delete all files and release the memory.
void	complete()	Finally, complete add.
int	getNumSpillFiles()
long	getSpillInBytes()
long	getUsedMemoryInBytes()
ResettableExternalBuffer.BufferIterator	newIterator()	Get a new iterator starting from first row.
ResettableExternalBuffer.BufferIterator	newIterator(int beginRow)	Get a new iterator starting from the `beginRow`-th row.
void	reset()	Re-initialize the buffer state.
int	size()

Methods inherited from class java.lang.Object

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

Field Details

MIN_NUM_MEMORY

public static final int MIN_NUM_MEMORY

The minimum number of segments that are required, 320 KibiBytes.

See Also:

• Constant Field Values

Constructor Details

ResettableExternalBuffer

public ResettableExternalBuffer(org.apache.flink.runtime.io.disk.iomanager.IOManager ioManager,
 LazyMemorySegmentPool pool,
 AbstractRowDataSerializer serializer,
 boolean isRowAllInFixedPart)

Method Details

reset

public void reset()

Description copied from interface: ResettableRowBuffer

Re-initialize the buffer state.

Specified by:

reset in interface ResettableRowBuffer

add

public void add(org.apache.flink.table.data.RowData row)
         throws IOException

Description copied from interface: ResettableRowBuffer

Appends the specified row to the end of this buffer.

Specified by:

add in interface ResettableRowBuffer

Throws:

IOException

complete

public void complete()

Description copied from interface: ResettableRowBuffer

Finally, complete add.

Specified by:

complete in interface ResettableRowBuffer

newIterator

public ResettableExternalBuffer.BufferIterator newIterator()

Description copied from interface: ResettableRowBuffer

Get a new iterator starting from first row.

Specified by:

newIterator in interface ResettableRowBuffer

newIterator

public ResettableExternalBuffer.BufferIterator newIterator(int beginRow)

Description copied from interface: ResettableRowBuffer

Get a new iterator starting from the `beginRow`-th row. `beginRow` is 0-indexed.

Specified by:

newIterator in interface ResettableRowBuffer

close

public void close()

Delete all files and release the memory.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

size

public int size()

getUsedMemoryInBytes

public long getUsedMemoryInBytes()

getNumSpillFiles

public int getNumSpillFiles()

getSpillInBytes

public long getSpillInBytes()