Package io.grpc.netty

Class WriteBufferingAndExceptionHandler

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.channel.ChannelDuplexHandler

io.grpc.netty.WriteBufferingAndExceptionHandler

All Implemented Interfaces:

io.netty.channel.ChannelHandler, io.netty.channel.ChannelInboundHandler, io.netty.channel.ChannelOutboundHandler

final class WriteBufferingAndExceptionHandler
extends io.netty.channel.ChannelDuplexHandler

Buffers all writes until either writeBufferedAndRemove(ChannelHandlerContext) or failWrites(Throwable) is called. This handler allows us to write to a Channel before we are allowed to write to it officially i.e. before it's active or the TLS Handshake is complete.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static final class	WriteBufferingAndExceptionHandler.ChannelWrite

Nested classes/interfaces inherited from interface io.netty.channel.ChannelHandler

io.netty.channel.ChannelHandler.Sharable

Field Summary

Fields

Modifier and Type	Field	Description
private final Queue<WriteBufferingAndExceptionHandler.ChannelWrite>	bufferedWrites
private Throwable	failCause
private boolean	flushRequested
private static final Logger	logger
private final io.netty.channel.ChannelHandler	next
private boolean	writing

Constructor Summary

Constructors

Constructor	Description
WriteBufferingAndExceptionHandler(io.netty.channel.ChannelHandler next)

Method Summary

Modifier and Type	Method	Description
void	channelInactive(io.netty.channel.ChannelHandlerContext ctx)	If this channel becomes inactive, then notify all buffered writes that we failed.
void	channelRead(io.netty.channel.ChannelHandlerContext ctx, Object msg)
void	close(io.netty.channel.ChannelHandlerContext ctx, io.netty.channel.ChannelPromise future)	If we are still performing protocol negotiation, then this will propagate failures to all buffered writes.
void	connect(io.netty.channel.ChannelHandlerContext ctx, SocketAddress remoteAddress, SocketAddress localAddress, io.netty.channel.ChannelPromise promise)	Connect failures do not show up as channelInactive(io.netty.channel.ChannelHandlerContext) or exceptionCaught(io.netty.channel.ChannelHandlerContext, java.lang.Throwable), so it needs to be watched.
void	exceptionCaught(io.netty.channel.ChannelHandlerContext ctx, Throwable cause)
private void	failWrites(Throwable cause)	Propagate failures to all buffered writes.
void	flush(io.netty.channel.ChannelHandlerContext ctx)	Calls to this method will not trigger an immediate flush.
void	handlerAdded(io.netty.channel.ChannelHandlerContext ctx)
void	handlerRemoved(io.netty.channel.ChannelHandlerContext ctx)
void	write(io.netty.channel.ChannelHandlerContext ctx, Object msg, io.netty.channel.ChannelPromise promise)	Buffers the write until either writeBufferedAndRemove(ChannelHandlerContext) is called, or we have somehow failed.
(package private) final void	writeBufferedAndRemove(io.netty.channel.ChannelHandlerContext ctx)

Methods inherited from class io.netty.channel.ChannelDuplexHandler

bind, deregister, disconnect, read

Methods inherited from class io.netty.channel.ChannelInboundHandlerAdapter

channelActive, channelReadComplete, channelRegistered, channelUnregistered, channelWritabilityChanged, userEventTriggered

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

ensureNotSharable, isSharable

Methods inherited from class java.lang.Object

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

Field Details

logger

private static final Logger logger

bufferedWrites

private final Queue<WriteBufferingAndExceptionHandler.ChannelWrite> bufferedWrites

next

private final io.netty.channel.ChannelHandler next

writing

private boolean writing

flushRequested

private boolean flushRequested

failCause

private Throwable failCause

Constructor Details

WriteBufferingAndExceptionHandler

WriteBufferingAndExceptionHandler(io.netty.channel.ChannelHandler next)

Method Details

handlerAdded

public void handlerAdded(io.netty.channel.ChannelHandlerContext ctx)
                  throws Exception

Specified by:

handlerAdded in interface io.netty.channel.ChannelHandler

Overrides:

handlerAdded in class io.netty.channel.ChannelHandlerAdapter

Throws:

Exception

handlerRemoved

public void handlerRemoved(io.netty.channel.ChannelHandlerContext ctx)
                    throws Exception

Specified by:

handlerRemoved in interface io.netty.channel.ChannelHandler

Overrides:

handlerRemoved in class io.netty.channel.ChannelHandlerAdapter

Throws:

Exception

channelInactive

public void channelInactive(io.netty.channel.ChannelHandlerContext ctx)

If this channel becomes inactive, then notify all buffered writes that we failed.

Specified by:

channelInactive in interface io.netty.channel.ChannelInboundHandler

Overrides:

channelInactive in class io.netty.channel.ChannelInboundHandlerAdapter

exceptionCaught

public void exceptionCaught(io.netty.channel.ChannelHandlerContext ctx,
 Throwable cause)

Specified by:

exceptionCaught in interface io.netty.channel.ChannelHandler

Specified by:

exceptionCaught in interface io.netty.channel.ChannelInboundHandler

Overrides:

exceptionCaught in class io.netty.channel.ChannelInboundHandlerAdapter

write

public void write(io.netty.channel.ChannelHandlerContext ctx,
 Object msg,
 io.netty.channel.ChannelPromise promise)

Buffers the write until either writeBufferedAndRemove(ChannelHandlerContext) is called, or we have somehow failed. If we have already failed in the past, then the write will fail immediately.

Specified by:

write in interface io.netty.channel.ChannelOutboundHandler

Overrides:

write in class io.netty.channel.ChannelDuplexHandler

connect

public void connect(io.netty.channel.ChannelHandlerContext ctx,
 SocketAddress remoteAddress,
 SocketAddress localAddress,
 io.netty.channel.ChannelPromise promise)
             throws Exception

Connect failures do not show up as channelInactive(io.netty.channel.ChannelHandlerContext) or exceptionCaught(io.netty.channel.ChannelHandlerContext, java.lang.Throwable), so it needs to be watched.

Specified by:

connect in interface io.netty.channel.ChannelOutboundHandler

Overrides:

connect in class io.netty.channel.ChannelDuplexHandler

Throws:

Exception

channelRead

public void channelRead(io.netty.channel.ChannelHandlerContext ctx,
 Object msg)

Specified by:

channelRead in interface io.netty.channel.ChannelInboundHandler

Overrides:

channelRead in class io.netty.channel.ChannelInboundHandlerAdapter

flush

public void flush(io.netty.channel.ChannelHandlerContext ctx)

Calls to this method will not trigger an immediate flush. The flush will be deferred until writeBufferedAndRemove(ChannelHandlerContext).

Specified by:

flush in interface io.netty.channel.ChannelOutboundHandler

Overrides:

flush in class io.netty.channel.ChannelDuplexHandler

close

public void close(io.netty.channel.ChannelHandlerContext ctx,
 io.netty.channel.ChannelPromise future)
           throws Exception

If we are still performing protocol negotiation, then this will propagate failures to all buffered writes.

Specified by:

close in interface io.netty.channel.ChannelOutboundHandler

Overrides:

close in class io.netty.channel.ChannelDuplexHandler

Throws:

Exception

writeBufferedAndRemove

final void writeBufferedAndRemove(io.netty.channel.ChannelHandlerContext ctx)

failWrites

private void failWrites(Throwable cause)

Propagate failures to all buffered writes.