alluxio.fuse.file

Class FusePositionReadOrOutStream

java.lang.Object

alluxio.fuse.file.FusePositionReadOrOutStream

All Implemented Interfaces:

FuseFileStream, AutoCloseable

@ThreadSafe
public class FusePositionReadOrOutStream
extends Object
implements FuseFileStream

An implementation for FuseFileStream for read only or write only workloads. Fuse can open file for reading and writing concurrently but Alluxio only support read-only or write-only workloads. This class will be used as write only stream if O_TRUNC flag is provided or first operation is write() or truncate(), will be used as read only stream otherwise.

Method Summary

Modifier and Type	Method and Description
void	close() Closes the stream and releases the lock.
void	closeStream() Closes the stream without releasing the locking resource.
static FusePositionReadOrOutStream	create(FileSystem fileSystem, AuthPolicy authPolicy, FuseReadWriteLockManager lockManager, AlluxioURI uri, int flags, long mode) Creates a FuseFileInOrOutStream.
void	flush() Flushes the stream.
FileStatus	getFileStatus()
boolean	isClosed()
boolean	isReadOnly()
int	read(ByteBuffer buf, long size, long offset) Reads data from the stream.
void	releaseLock() Releases the lock resource the stream obtained.
void	truncate(long size) Truncates the file to the given size.
void	write(ByteBuffer buf, long size, long offset) Writes data to the stream.

Methods inherited from class java.lang.Object

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

Method Detail

create

public static FusePositionReadOrOutStream create(FileSystem fileSystem,
                                                 AuthPolicy authPolicy,
                                                 FuseReadWriteLockManager lockManager,
                                                 AlluxioURI uri,
                                                 int flags,
                                                 long mode)

Creates a FuseFileInOrOutStream.

Parameters:

fileSystem - the Alluxio file system

authPolicy - the Authentication policy

lockManager - the lock manager

uri - the alluxio uri

flags - the fuse create/open flags

mode - the filesystem mode, -1 if not set

Returns:

a FuseFileInOrOutStream

read

public int read(ByteBuffer buf,
                long size,
                long offset)

Description copied from interface: FuseFileStream

Reads data from the stream.

Specified by:

read in interface FuseFileStream

Parameters:

buf - the byte buffer to read data to

size - the size to read

offset - the offset of the target stream to begin reading

Returns:

the bytes read

write

public void write(ByteBuffer buf,
                  long size,
                  long offset)

Description copied from interface: FuseFileStream

Writes data to the stream.

Specified by:

write in interface FuseFileStream

Parameters:

buf - the byte buffer to read data from and write to the stream

size - the size to write

offset - the offset to write

getFileStatus

public FileStatus getFileStatus()

Specified by:

getFileStatus in interface FuseFileStream

Returns:

file status

flush

public void flush()

Description copied from interface: FuseFileStream

Flushes the stream.

Specified by:

flush in interface FuseFileStream

truncate

public void truncate(long size)

Description copied from interface: FuseFileStream

Truncates the file to the given size.

Specified by:

truncate in interface FuseFileStream

Parameters:

size - the truncate size

close

public void close()

Description copied from interface: FuseFileStream

Closes the stream and releases the lock.

Specified by:

close in interface FuseFileStream

Specified by:

close in interface AutoCloseable

isClosed

public boolean isClosed()

Specified by:

isClosed in interface FuseFileStream

Returns:

if the stream is closed

isReadOnly

public boolean isReadOnly()

Specified by:

isReadOnly in interface FuseFileStream

Returns:

if this stream is for read only

releaseLock

public void releaseLock()

Description copied from interface: FuseFileStream

Releases the lock resource the stream obtained.

Specified by:

releaseLock in interface FuseFileStream

closeStream

public void closeStream()

Description copied from interface: FuseFileStream

Closes the stream without releasing the locking resource.

Specified by:

closeStream in interface FuseFileStream