io.datakernel.file

Class AsyncFile

java.lang.Object

io.datakernel.file.AsyncFile

public final class AsyncFile
extends Object

This class represents a file with asynchronous capabilities.

Method Summary

Modifier and Type	Method and Description
Stage<Void>	close() Closes the channel
static Stage<Void>	copy(ExecutorService executor, Path source, Path target, CopyOption... options) Copies a file to a target file.
static Stage<Void>	createDirectories(ExecutorService executor, Path dir, FileAttribute<?>[] attrs) Creates a directory by creating all nonexistent parent directories first.
static Stage<Void>	createDirectory(ExecutorService executor, Path dir, FileAttribute<?>[] attrs) Creates a new directory.
static Stage<Void>	delete(ExecutorService executor, Path path) Concurrently deletes the file.
Stage<Void>	force(boolean metaData) Forces any updates to this file to be written to the storage device that contains it.
Stage<Void>	forceAndClose(boolean forceMetadata) Forces physical write and then closes the channel
FileChannel	getChannel()
ExecutorService	getExecutor()
boolean	isOpen()
static Stage<Void>	move(ExecutorService executor, Path source, Path target, CopyOption... options) Moves or renames a file to a target file.
static AsyncFile	open(ExecutorService executor, Path path, OpenOption[] openOptions) Synchronously opens file
static AsyncFile	open(ExecutorService executor, Path path, OpenOption[] openOptions, Object mutexLock)
static Stage<AsyncFile>	openAsync(ExecutorService executor, Path path, OpenOption[] openOptions) Asynchronously opens file
static Stage<AsyncFile>	openAsync(ExecutorService executor, Path path, OpenOption[] openOptions, Object mutexLock)
Stage<ByteBuf>	read() Asynchronously reads all bytes from this file into a buffer.
Stage<Void>	read(ByteBuf buf, long position) Asynchronously reads a sequence of bytes from this channel into the given buffer, starting at the given position.
Stage<ByteBuf>	read(long position) Asynchronously reads all bytes from this file into a buffer starting at given position.
static Stage<ByteBuf>	readFile(ExecutorService executor, Path path) Reads all bytes from this channel into the given buffer.
static Stage<Long>	size(ExecutorService executor, Path path) Checks the file size.
String	toString()
Stage<Void>	truncate(long size) Truncates this file to the given size.
Stage<Void>	write(ByteBuf buf) Asynchronously writes all bytes of the buffer into this file at its internal position.
Stage<Void>	write(ByteBuf buf, long position) Asynchronously writes all bytes of the buffer into this file starting at given position.
static Stage<Void>	writeNewFile(ExecutorService executor, Path path, ByteBuf buf) Creates new file and writes a sequence of bytes to this file from the given buffer, starting at the given file position.

Methods inherited from class java.lang.Object

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

Method Detail

open

public static AsyncFile open(ExecutorService executor,
                             Path path,
                             OpenOption[] openOptions)
                      throws IOException

Synchronously opens file

Parameters:

executor - executor for running tasks in other thread

path - the path of the file to open or create

openOptions - options specifying how the file is opened

Throws:

IOException

open

public static AsyncFile open(ExecutorService executor,
                             Path path,
                             OpenOption[] openOptions,
                             Object mutexLock)
                      throws IOException

Throws:

IOException

openAsync

public static Stage<AsyncFile> openAsync(ExecutorService executor,
                                         Path path,
                                         OpenOption[] openOptions)

Asynchronously opens file

Parameters:

executor - executor for running tasks in other thread

path - the path of the file to open or create

openOptions - options specifying how the file is opened

openAsync

public static Stage<AsyncFile> openAsync(ExecutorService executor,
                                         Path path,
                                         OpenOption[] openOptions,
                                         Object mutexLock)

delete

public static Stage<Void> delete(ExecutorService executor,
                                 Path path)

Concurrently deletes the file.

Parameters:

path - the path of the file to open or create

size

public static Stage<Long> size(ExecutorService executor,
                               Path path)

Checks the file size. For non-regular or non-existing files returns null

Parameters:

executor - executor for running tasks in other thread

path - the path of the file to check

Returns:

file size if given path is a regular file and null if it is a directory or it does not exist

move

public static Stage<Void> move(ExecutorService executor,
                               Path source,
                               Path target,
                               CopyOption... options)

Moves or renames a file to a target file.

Parameters:

executor - executor for running tasks in other thread

source - the path to the file to move

target - the path to the target file (may be associated with a different provider to the source path)

options - options specifying how the move should be done

copy

public static Stage<Void> copy(ExecutorService executor,
                               Path source,
                               Path target,
                               CopyOption... options)

Copies a file to a target file.

Parameters:

executor - executor for running tasks in other thread

source - the path to the file to copy

target - the path to the target file (may be associated with a different provider to the source path)

options - options specifying how the move should be done

createDirectory

public static Stage<Void> createDirectory(ExecutorService executor,
                                          Path dir,
                                          @Nullable
                                          FileAttribute<?>[] attrs)

Creates a new directory.

Parameters:

executor - executor for running tasks in other thread

dir - the directory to create

attrs - an optional list of file attributes to set atomically when creating the directory

createDirectories

public static Stage<Void> createDirectories(ExecutorService executor,
                                            Path dir,
                                            @Nullable
                                            FileAttribute<?>[] attrs)

Creates a directory by creating all nonexistent parent directories first.

Parameters:

executor - executor for running tasks in other thread

dir - the directory to create

attrs - an optional list of file attributes to set atomically when creating the directory

readFile

public static Stage<ByteBuf> readFile(ExecutorService executor,
                                      Path path)

Reads all bytes from this channel into the given buffer.

Parameters:

path - the path of the file to read

writeNewFile

public static Stage<Void> writeNewFile(ExecutorService executor,
                                       Path path,
                                       ByteBuf buf)

Creates new file and writes a sequence of bytes to this file from the given buffer, starting at the given file position. If file exists then stage fails with exception.

Parameters:

path - the path of the file to create and write

buf - the buffer from which bytes are to be transferred byteBuffer

write

public Stage<Void> write(ByteBuf buf)

Asynchronously writes all bytes of the buffer into this file at its internal position.

Parameters:

buf - byte buffer to be written

write

public Stage<Void> write(ByteBuf buf,
                         long position)

Asynchronously writes all bytes of the buffer into this file starting at given position.

Parameters:

position - offset from which bytes will be written to the file

buf - byte buffer to be written

read

public Stage<ByteBuf> read()

Asynchronously reads all bytes from this file into a buffer.

read

public Stage<ByteBuf> read(long position)

Asynchronously reads all bytes from this file into a buffer starting at given position.

Parameters:

position - offset from which bytes of the file will be read

read

public Stage<Void> read(ByteBuf buf,
                        long position)

Asynchronously reads a sequence of bytes from this channel into the given buffer, starting at the given position. Reads are happenning in other thread(s).

Parameters:

buf - the buffer into which bytes are to be transferred

position - the file position at which the transfer is to begin; must be non-negative

forceAndClose

public Stage<Void> forceAndClose(boolean forceMetadata)

Forces physical write and then closes the channel

Parameters:

forceMetadata - whether or not to force metadata writes too

close

public Stage<Void> close()

Closes the channel

truncate

public Stage<Void> truncate(long size)

Truncates this file to the given size.

Parameters:

size - the new size, a non-negative byte count

force

public Stage<Void> force(boolean metaData)

Forces any updates to this file to be written to the storage device that contains it.

Parameters:

metaData - if true then this method is required to force changes of both file content and metadata to be written to storage; otherwise, it need only force content changes to be written

getExecutor

public ExecutorService getExecutor()

getChannel

public FileChannel getChannel()

isOpen

public boolean isOpen()

toString

public String toString()

Overrides:

toString in class Object