org.apache.flink.table.runtime.io

Class CompressedBlockChannelReader

java.lang.Object

org.apache.flink.table.runtime.io.CompressedBlockChannelReader

All Implemented Interfaces:

BlockChannelReader<MemorySegment>, FileIOChannel, RequestDoneCallback<Buffer>, BufferRecycler

public class CompressedBlockChannelReader
extends Object
implements BlockChannelReader<MemorySegment>, RequestDoneCallback<Buffer>, BufferRecycler

Compressed block channel reader provides a scenario where MemorySegment must be maintained.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.flink.runtime.io.disk.iomanager.FileIOChannel

FileIOChannel.Enumerator, FileIOChannel.ID

Nested classes/interfaces inherited from interface org.apache.flink.runtime.io.network.buffer.BufferRecycler

BufferRecycler.DummyBufferRecycler

Constructor Summary

Constructors

Constructor and Description
CompressedBlockChannelReader(IOManager ioManager, FileIOChannel.ID channel, LinkedBlockingQueue<MemorySegment> blockQueue, BlockCompressionFactory codecFactory, int preferBlockSize, int segmentSize)

Method Summary

Modifier and Type	Method and Description
void	close() Closes the channel.
void	closeAndDelete() Closes the channel and deletes the underlying file.
void	deleteChannel() Deletes the file underlying this I/O channel.
FileIOChannel.ID	getChannelID() Gets the channel ID of this I/O channel.
MemorySegment	getNextReturnedBlock() Gets the next memory segment that has been filled with data by the reader.
FileChannel	getNioFileChannel()
LinkedBlockingQueue<MemorySegment>	getReturnQueue() Gets the queue in which the full memory segments are queued after the read is complete.
long	getSize() Gets the size (in bytes) of the file underlying the channel.
boolean	isClosed() Checks whether the channel has been closed.
void	readBlock(MemorySegment segment) Issues a read request, which will fill the given segment with the next block in the underlying file channel.
void	recycle(MemorySegment segment) Recycles the MemorySegment to its original BufferPool instance.
void	requestFailed(Buffer buffer, IOException e)
void	requestSuccessful(Buffer request)
void	seekToPosition(long position)

Methods inherited from class java.lang.Object

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

Constructor Detail

CompressedBlockChannelReader

public CompressedBlockChannelReader(IOManager ioManager,
                                    FileIOChannel.ID channel,
                                    LinkedBlockingQueue<MemorySegment> blockQueue,
                                    BlockCompressionFactory codecFactory,
                                    int preferBlockSize,
                                    int segmentSize)
                             throws IOException

Throws:

IOException

Method Detail

readBlock

public void readBlock(MemorySegment segment)
               throws IOException

Description copied from interface: BlockChannelReader

Issues a read request, which will fill the given segment with the next block in the underlying file channel. Once the read request is fulfilled, the segment will be added to this reader's return queue.

Specified by:

readBlock in interface BlockChannelReader<MemorySegment>

Parameters:

segment - The segment to read the block into.

Throws:

IOException - Thrown, when the reader encounters an I/O error.

seekToPosition

public void seekToPosition(long position)
                    throws IOException

Specified by:

seekToPosition in interface BlockChannelReader<MemorySegment>

Throws:

IOException

getNextReturnedBlock

public MemorySegment getNextReturnedBlock()
                                   throws IOException

Description copied from interface: BlockChannelReader

Gets the next memory segment that has been filled with data by the reader. This method blocks until such a segment is available, or until an error occurs in the reader, or the reader is closed.

WARNING: If this method is invoked without any segment ever returning (for example, because the BlockChannelReader.readBlock(T) method has not been invoked appropriately), the method may block forever.

Specified by:

getNextReturnedBlock in interface BlockChannelReader<MemorySegment>

Returns:

The next memory segment from the reader's return queue.

Throws:

IOException - Thrown, if an I/O error occurs in the reader while waiting for the request to return.

getReturnQueue

public LinkedBlockingQueue<MemorySegment> getReturnQueue()

Description copied from interface: BlockChannelReader

Gets the queue in which the full memory segments are queued after the read is complete.

Specified by:

getReturnQueue in interface BlockChannelReader<MemorySegment>

Returns:

The queue with the full memory segments.

getChannelID

public FileIOChannel.ID getChannelID()

Description copied from interface: FileIOChannel

Gets the channel ID of this I/O channel.

Specified by:

getChannelID in interface FileIOChannel

Returns:

The channel ID.

getSize

public long getSize()
             throws IOException

Description copied from interface: FileIOChannel

Gets the size (in bytes) of the file underlying the channel.

Specified by:

getSize in interface FileIOChannel

Throws:

IOException

isClosed

public boolean isClosed()

Description copied from interface: FileIOChannel

Checks whether the channel has been closed.

Specified by:

isClosed in interface FileIOChannel

Returns:

True if the channel has been closed, false otherwise.

close

public void close()
           throws IOException

Description copied from interface: FileIOChannel

Closes the channel. For asynchronous implementations, this method waits until all pending requests are handled. Even if an exception interrupts the closing, the underlying FileChannel is closed.

Specified by:

close in interface FileIOChannel

Throws:

IOException - Thrown, if an error occurred while waiting for pending requests.

deleteChannel

public void deleteChannel()

Description copied from interface: FileIOChannel

Deletes the file underlying this I/O channel.

Specified by:

deleteChannel in interface FileIOChannel

closeAndDelete

public void closeAndDelete()
                    throws IOException

Description copied from interface: FileIOChannel

Closes the channel and deletes the underlying file. For asynchronous implementations, this method waits until all pending requests are handled.

Specified by:

closeAndDelete in interface FileIOChannel

Throws:

IOException - Thrown, if an error occurred while waiting for pending requests.

getNioFileChannel

public FileChannel getNioFileChannel()

Specified by:

getNioFileChannel in interface FileIOChannel

requestSuccessful

public void requestSuccessful(Buffer request)

Specified by:

requestSuccessful in interface RequestDoneCallback<Buffer>

requestFailed

public void requestFailed(Buffer buffer,
                          IOException e)

Specified by:

requestFailed in interface RequestDoneCallback<Buffer>

recycle

public void recycle(MemorySegment segment)

Description copied from interface: BufferRecycler

Recycles the MemorySegment to its original BufferPool instance.

Specified by:

recycle in interface BufferRecycler

Parameters:

segment - The memory segment to be recycled.