Package org.apache.cassandra.net

Class AsyncStreamingOutputPlus

java.lang.Object

java.io.OutputStream

org.apache.cassandra.io.util.DataOutputStreamPlus

org.apache.cassandra.io.util.BufferedDataOutputStreamPlus

org.apache.cassandra.net.AsyncChannelOutputPlus

org.apache.cassandra.net.AsyncStreamingOutputPlus

All Implemented Interfaces:

Closeable, DataOutput, Flushable, AutoCloseable, DataOutputPlus, StreamingDataOutputPlus

public class AsyncStreamingOutputPlus
extends AsyncChannelOutputPlus
implements StreamingDataOutputPlus

A DataOutputStreamPlus that writes ASYNCHRONOUSLY to a Netty Channel. The close() and flush() methods synchronously wait for pending writes, and will propagate any exceptions encountered in writing them to the wire. The correctness of this class depends on the ChannelPromise we create against a Channel always being completed, which appears to be a guarantee provided by Netty so long as the event loop is running.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.cassandra.net.AsyncChannelOutputPlus

AsyncChannelOutputPlus.FlushException

Nested classes/interfaces inherited from interface org.apache.cassandra.streaming.StreamingDataOutputPlus

StreamingDataOutputPlus.BufferSupplier, StreamingDataOutputPlus.RateLimiter, StreamingDataOutputPlus.Write

Field Summary

Fields inherited from class org.apache.cassandra.io.util.BufferedDataOutputStreamPlus

buffer

Constructor Summary

Constructors

Constructor	Description
AsyncStreamingOutputPlus(io.netty.channel.Channel channel)

Method Summary

Modifier and Type	Method	Description
void	discard()	Discard any buffered data, and the buffers that contain it.
protected void	doFlush(int count)
long	position()	Returns the current position of the underlying target like a file-pointer or the position withing a buffer.
long	writeFileToChannel(FileChannel file, StreamingDataOutputPlus.RateLimiter limiter)	Writes all data in file channel to stream: * For zero-copy-streaming, 1MiB at a time, with at most 2MiB in flight at once.
int	writeToChannel(StreamingDataOutputPlus.Write write, StreamingDataOutputPlus.RateLimiter limiter)	Provide a lambda that can request a buffer of suitable size, then fill the buffer and have that buffer written and flushed to the underlying channel, without having to handle buffer allocation, lifetime or cleanup, including in case of exceptions.

Methods inherited from class org.apache.cassandra.net.AsyncChannelOutputPlus

beginFlush, close, flush, flushed, flushedToNetwork, newDefaultChannel, parkUntilFlushed, releaseSpace

Methods inherited from class org.apache.cassandra.io.util.BufferedDataOutputStreamPlus

allocate, order, write, write, write, write, writeBoolean, writeByte, writeBytes, writeChar, writeChars, writeDouble, writeFloat, writeInt, writeLong, writeMostSignificantBytes, writeShort, writeUTF

Methods inherited from class org.apache.cassandra.io.util.DataOutputStreamPlus

retrieveTemporaryBuffer

Methods inherited from class java.io.OutputStream

nullOutputStream

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.io.Closeable

close

Methods inherited from interface java.io.DataOutput

write, write, write, writeBoolean, writeByte, writeBytes, writeChar, writeChars, writeDouble, writeFloat, writeInt, writeLong, writeShort, writeUTF

Methods inherited from interface org.apache.cassandra.io.util.DataOutputPlus

bytesLeftInPage, hasPosition, maxBytesInPage, paddedPosition, padToPageBoundary, write, write, writeMostSignificantBytes, writeUnsignedVInt, writeUnsignedVInt, writeUnsignedVInt32, writeVInt, writeVInt, writeVInt32

Methods inherited from interface org.apache.cassandra.streaming.StreamingDataOutputPlus

flush

Constructor Details

AsyncStreamingOutputPlus

public AsyncStreamingOutputPlus(io.netty.channel.Channel channel)

Method Details

doFlush

protected void doFlush(int count)
                throws IOException

Specified by:

doFlush in class AsyncChannelOutputPlus

Throws:

IOException

position

public long position()

Description copied from interface: DataOutputPlus

Returns the current position of the underlying target like a file-pointer or the position withing a buffer. Not every implementation may support this functionality. Whether or not this functionality is supported can be checked via the DataOutputPlus.hasPosition().

Specified by:

position in interface DataOutputPlus

Specified by:

position in class AsyncChannelOutputPlus

writeToChannel

public int writeToChannel(StreamingDataOutputPlus.Write write,
 StreamingDataOutputPlus.RateLimiter limiter)
                   throws IOException

Provide a lambda that can request a buffer of suitable size, then fill the buffer and have that buffer written and flushed to the underlying channel, without having to handle buffer allocation, lifetime or cleanup, including in case of exceptions.

Any exception thrown by the Write will be propagated to the caller, after any buffer is cleaned up.

Specified by:

writeToChannel in interface StreamingDataOutputPlus

Throws:

IOException

writeFileToChannel

public long writeFileToChannel(FileChannel file,
 StreamingDataOutputPlus.RateLimiter limiter)
                        throws IOException

Writes all data in file channel to stream:
* For zero-copy-streaming, 1MiB at a time, with at most 2MiB in flight at once.
* For streaming with SSL, 64KiB at a time, with at most 32+64KiB (default low water mark + batch size) in flight.

This method takes ownership of the provided FileChannel.

WARNING: this method blocks only for permission to write to the netty channel; it exits before the FileRegion(zero-copy) or ByteBuffer(ssl) is flushed to the network.

Specified by:

writeFileToChannel in interface StreamingDataOutputPlus

Throws:

IOException

discard

public void discard()

Discard any buffered data, and the buffers that contain it. May be invoked instead of AsyncChannelOutputPlus.close() if we terminate exceptionally.

Specified by:

discard in class AsyncChannelOutputPlus