alluxio.client.block.stream

Class BufferCachingGrpcDataReader

java.lang.Object

alluxio.client.block.stream.BufferCachingGrpcDataReader

@NotThreadSafe
public class BufferCachingGrpcDataReader
extends Object

A gRPC data reader that responsible for reading from a specific block. The current implementation cached the block data from the beginning to the largest index being read.

Field Summary

Fields

Modifier and Type	Field and Description
protected long	mPosToRead The next pos to read.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	BufferCachingGrpcDataReader(WorkerNetAddress address, CloseableResource<BlockWorkerClient> client, long dataTimeoutMs, ReadRequest readRequest, GrpcBlockingStream<ReadRequest,ReadResponse> stream) Creates an instance of BufferCachingGrpcDataReader.

Method Summary

Modifier and Type	Method and Description
void	close() Closes the BufferCachingGrpcDataReader.
static BufferCachingGrpcDataReader	create(FileSystemContext context, WorkerNetAddress address, ReadRequest readRequest) Creates an instance of BufferCachingGrpcDataReader for block reads.
int	deRef() Decreases the reference count and return the current count.
int	getRefCount()
protected DataBuffer	readChunk() Reads a chunk of data.
DataBuffer	readChunk(int index) Reads a specific chunk from the block.
int	ref() Increases the reference count and return the current count.

Methods inherited from class java.lang.Object

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

Field Detail

mPosToRead

protected long mPosToRead

The next pos to read.

Constructor Detail

BufferCachingGrpcDataReader

protected BufferCachingGrpcDataReader(WorkerNetAddress address,
                                      CloseableResource<BlockWorkerClient> client,
                                      long dataTimeoutMs,
                                      ReadRequest readRequest,
                                      GrpcBlockingStream<ReadRequest,ReadResponse> stream)

Creates an instance of BufferCachingGrpcDataReader.

Parameters:

address - the data server address

client - the block worker client to read data from

dataTimeoutMs - the maximum time to wait for a data response

readRequest - the read request

stream - the underlying gRPC stream to read data

Method Detail

readChunk

@Nullable
public DataBuffer readChunk(int index)
                               throws IOException

Reads a specific chunk from the block.

Parameters:

index - the chunk index

Returns:

the chunk data if exists

Throws:

IOException

readChunk

@Nullable
protected DataBuffer readChunk()
                                  throws IOException

Reads a chunk of data.

Returns:

a chunk of data

Throws:

IOException

close

public void close()
           throws IOException

Closes the BufferCachingGrpcDataReader.

Throws:

IOException

ref

public int ref()

Increases the reference count and return the current count.

Returns:

the incremented count

deRef

public int deRef()

Decreases the reference count and return the current count.

Returns:

the decremented count

getRefCount

public int getRefCount()

Returns:

the current count

create

public static BufferCachingGrpcDataReader create(FileSystemContext context,
                                                 WorkerNetAddress address,
                                                 ReadRequest readRequest)
                                          throws IOException

Creates an instance of BufferCachingGrpcDataReader for block reads.

Parameters:

context - the file system context

address - the worker address

readRequest - the read request

Returns:

a new BufferCachingGrpcDataReader

Throws:

IOException