com.mysql.cj.protocol

Class SerializingBufferWriter

java.lang.Object

com.mysql.cj.protocol.SerializingBufferWriter

All Implemented Interfaces:

java.nio.channels.CompletionHandler<java.lang.Long,java.lang.Void>

public class SerializingBufferWriter
extends java.lang.Object
implements java.nio.channels.CompletionHandler<java.lang.Long,java.lang.Void>

A layer over AsynchronousSocketChannel that serializes all incoming write requests. This means we queue any incoming buffer and don't begin writing it until the previous buffer has been written fully. All buffers are transmitted atomically with respect to the caller/callback.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.nio.channels.AsynchronousSocketChannel	channel

Constructor Summary

Constructors

Constructor and Description
SerializingBufferWriter(java.nio.channels.AsynchronousSocketChannel channel)

Method Summary

Modifier and Type	Method and Description
void	completed(java.lang.Long bytesWritten, java.lang.Void v) Completion handler for channel writes.
void	failed(java.lang.Throwable t, java.lang.Void v)
void	queueBuffer(java.nio.ByteBuffer buf, java.nio.channels.CompletionHandler<java.lang.Long,java.lang.Void> callback) Queue a buffer to be written to the channel.
void	setChannel(java.nio.channels.AsynchronousSocketChannel channel) Allow overwriting the channel once the writer has been established.

Methods inherited from class java.lang.Object

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

Field Detail

channel

protected java.nio.channels.AsynchronousSocketChannel channel

Constructor Detail

SerializingBufferWriter

public SerializingBufferWriter(java.nio.channels.AsynchronousSocketChannel channel)

Method Detail

queueBuffer

public void queueBuffer(java.nio.ByteBuffer buf,
                        java.nio.channels.CompletionHandler<java.lang.Long,java.lang.Void> callback)

Queue a buffer to be written to the channel. This method uses a mutex on the buffer list to synchronize for the following cases:

• The buffer list becomes empty after we check and miss writing to the channel.
• LinkedList is not thread-safe.

Parameters:

buf - ByteBuffer

callback - CompletionHandler

completed

public void completed(java.lang.Long bytesWritten,
                      java.lang.Void v)

Completion handler for channel writes.

Specified by:

completed in interface java.nio.channels.CompletionHandler<java.lang.Long,java.lang.Void>

Parameters:

bytesWritten - number of processed bytes

v - Void

failed

public void failed(java.lang.Throwable t,
                   java.lang.Void v)

Specified by:

failed in interface java.nio.channels.CompletionHandler<java.lang.Long,java.lang.Void>

setChannel

public void setChannel(java.nio.channels.AsynchronousSocketChannel channel)

Allow overwriting the channel once the writer has been established. Required for SSL/TLS connections when the encryption doesn't start until we send the capability flag to X Plugin.

Parameters:

channel - AsynchronousSocketChannel