Package ratpack.file

Class FileIo

java.lang.Object

ratpack.file.FileIo

public class FileIo
extends java.lang.Object

Utilities for streaming to and from files.

Since:

1.5

Method Summary

Modifier and Type	Method	Description
static ratpack.exec.Promise<java.nio.channels.AsynchronousFileChannel>	open(java.nio.file.Path file, java.nio.file.OpenOption... options)	Creates a promise for an (open) async file channel.
static ratpack.exec.Promise<java.nio.channels.AsynchronousFileChannel>	open(java.nio.file.Path file, java.util.Set<? extends java.nio.file.OpenOption> options, java.nio.file.attribute.FileAttribute<?>... attrs)	Creates a promise for an (open) async file channel.
static ratpack.exec.Promise<io.netty.buffer.CompositeByteBuf>	read(ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file, io.netty.buffer.ByteBufAllocator allocator, int bufferSize)	Read the contents of a file from the given start until the given stop.
static ratpack.exec.Promise<io.netty.buffer.CompositeByteBuf>	read(ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file, io.netty.buffer.ByteBufAllocator allocator, int bufferSize, long start, long stop)	Read the contents of a file.
static ratpack.stream.TransformablePublisher<io.netty.buffer.ByteBuf>	readStream(ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file, io.netty.buffer.ByteBufAllocator allocator, int bufferSize)	Streams the entire contents of a file.
static ratpack.stream.TransformablePublisher<io.netty.buffer.ByteBuf>	readStream(ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file, io.netty.buffer.ByteBufAllocator allocator, int bufferSize, long start, long stop)	Streams the contents of a file.
static ratpack.exec.Operation	write(io.netty.buffer.ByteBuf bytes, long position, ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file)	Writes the given bytes to the given file, starting at the given position.
static ratpack.exec.Operation	write(io.netty.buffer.ByteBuf bytes, ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file)	Writes the given bytes to the given file, starting at the start.
static ratpack.exec.Promise<java.lang.Long>	write(Publisher<? extends io.netty.buffer.ByteBuf> publisher, long position, ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file)	Writes the bytes of the given publisher to the given file, returning the number of bytes written.
static ratpack.exec.Promise<java.lang.Long>	write(Publisher<? extends io.netty.buffer.ByteBuf> publisher, ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file)	Writes the bytes of the given publisher to the given file starting at the start, returning the number of bytes written.

Methods inherited from class java.lang.Object

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

Method Detail

open

public static ratpack.exec.Promise<java.nio.channels.AsynchronousFileChannel> open(java.nio.file.Path file,
                                                                                   java.nio.file.OpenOption... options)

Creates a promise for an (open) async file channel.

Uses AsynchronousFileChannel.open(Path, Set, ExecutorService, FileAttribute[]), but uses the current execution's event loop as the executor service and no file attributes.

Parameters:

file - The path of the file to open or create

options - Options specifying how the file is opened

Returns:

a promise for an open async file channel

See Also:

AsynchronousFileChannel.open(Path, Set, ExecutorService, FileAttribute[]), open(Path, Set, FileAttribute[])

open

public static ratpack.exec.Promise<java.nio.channels.AsynchronousFileChannel> open(java.nio.file.Path file,
                                                                                   java.util.Set<? extends java.nio.file.OpenOption> options,
                                                                                   java.nio.file.attribute.FileAttribute<?>... attrs)

Creates a promise for an (open) async file channel.

Uses AsynchronousFileChannel.open(Path, Set, ExecutorService, FileAttribute[]), but uses the current execution's event loop as the executor service.

Parameters:

file - The path of the file to open or create

options - Options specifying how the file is opened

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

Returns:

a promise for an open async file channel

See Also:

AsynchronousFileChannel.open(Path, Set, ExecutorService, FileAttribute[]), open(Path, OpenOption...)

write

public static ratpack.exec.Promise<java.lang.Long> write(Publisher<? extends io.netty.buffer.ByteBuf> publisher,
                                                         ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file)

Writes the bytes of the given publisher to the given file starting at the start, returning the number of bytes written.

Use open(Path, Set, FileAttribute[]) to create a file promise.

The file channel is closed on success or failure.

As file system writes are expensive, you may want to consider using ByteBufStreams.buffer(Publisher, long, int, ByteBufAllocator) to “buffer” the data in memory before writing to disk.

Parameters:

publisher - the bytes to write

file - a promise for the file to write to

Returns:

a promise for the number of bytes written

write

public static ratpack.exec.Promise<java.lang.Long> write(Publisher<? extends io.netty.buffer.ByteBuf> publisher,
                                                         long position,
                                                         ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file)

Writes the bytes of the given publisher to the given file, returning the number of bytes written.

Use open(Path, Set, FileAttribute[]) to create a file promise.

The file channel is closed on success or failure.

As file system writes are expensive, you may want to consider using ByteBufStreams.buffer(Publisher, long, int, ByteBufAllocator) to “buffer” the data in memory before writing to disk.

Parameters:

publisher - the bytes to write

position - the position in the file to start writing (must be >= 0)

file - a promise for the file to write to

Returns:

a promise for the number of bytes written

write

public static ratpack.exec.Operation write(io.netty.buffer.ByteBuf bytes,
                                           ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file)

Writes the given bytes to the given file, starting at the start. Use open(Path, Set, FileAttribute[]) to create a file promise.

The file channel is closed on success or failure.

Parameters:

bytes - the bytes to write

file - the file to write to

Returns:

a write operation

write

public static ratpack.exec.Operation write(io.netty.buffer.ByteBuf bytes,
                                           long position,
                                           ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file)

Writes the given bytes to the given file, starting at the given position. Use open(Path, Set, FileAttribute[]) to create a file promise.

The file channel is closed on success or failure.

Parameters:

bytes - the bytes to write

position - the position in the file to start writing

file - the file to write to

Returns:

a write operation

readStream

public static ratpack.stream.TransformablePublisher<io.netty.buffer.ByteBuf> readStream(ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file,
                                                                                        io.netty.buffer.ByteBufAllocator allocator,
                                                                                        int bufferSize,
                                                                                        long start,
                                                                                        long stop)

Streams the contents of a file.

Use open(Path, Set, FileAttribute[]) to create a file promise.

The file channel is closed on success or failure.

Parameters:

file - a promise for the file to write to

allocator - the allocator of byte bufs

bufferSize - the read buffer size (i.e. the size of each emitted buffer)

start - the position in the file to start reading from (must be >= 0)

stop - the position in the file to read up to (any value < 1 is treated as EOF)

Returns:

a publisher of the byte bufs

See Also:

readStream(Promise, ByteBufAllocator, int)

readStream

public static ratpack.stream.TransformablePublisher<io.netty.buffer.ByteBuf> readStream(ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file,
                                                                                        io.netty.buffer.ByteBufAllocator allocator,
                                                                                        int bufferSize)

Streams the entire contents of a file.

Use open(Path, Set, FileAttribute[]) to create a file promise.

The file channel is closed on success or failure.

Parameters:

file - a promise for the file to write to

allocator - the allocator of byte bufs

bufferSize - the read buffer size (i.e. the size of each emitted buffer)

Returns:

a publisher of the byte bufs

See Also:

readStream(Promise, ByteBufAllocator, int, long, long)

read

public static ratpack.exec.Promise<io.netty.buffer.CompositeByteBuf> read(ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file,
                                                                          io.netty.buffer.ByteBufAllocator allocator,
                                                                          int bufferSize,
                                                                          long start,
                                                                          long stop)

Read the contents of a file.

Use open(Path, Set, FileAttribute[]) to create a file promise.

The file channel is closed on success or failure.

Parameters:

file - a promise for the file to write to

allocator - the allocator of byte bufs

bufferSize - the read buffer size (i.e. the size of buffer used for each read operation)

Returns:

a publisher of the byte bufs

See Also:

readStream(Promise, ByteBufAllocator, int), read(Promise, ByteBufAllocator, int)

read

public static ratpack.exec.Promise<io.netty.buffer.CompositeByteBuf> read(ratpack.exec.Promise<? extends java.nio.channels.AsynchronousFileChannel> file,
                                                                          io.netty.buffer.ByteBufAllocator allocator,
                                                                          int bufferSize)

Read the contents of a file from the given start until the given stop.

Use open(Path, Set, FileAttribute[]) to create a file promise.

The file channel is closed on success or failure.

Parameters:

file - a promise for the file to write to

allocator - the allocator of byte bufs

bufferSize - the read buffer size (i.e. the size of buffer used for each read operation)

Returns:

a publisher of the byte bufs

See Also:

readStream(Promise, ByteBufAllocator, int, long, long), read(Promise, ByteBufAllocator, int, long, long)