io.grpc.netty

Class ProtocolNegotiators.AbstractBufferingHandler

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.channel.ChannelDuplexHandler

io.grpc.netty.ProtocolNegotiators.AbstractBufferingHandler

All Implemented Interfaces:

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

Enclosing class:

ProtocolNegotiators

public abstract static class ProtocolNegotiators.AbstractBufferingHandler
extends io.netty.channel.ChannelDuplexHandler

Buffers all writes until either writeBufferedAndRemove(ChannelHandlerContext) or fail(ChannelHandlerContext, 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/interfaces inherited from interface io.netty.channel.ChannelHandler

io.netty.channel.ChannelHandler.Sharable

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractBufferingHandler(io.netty.channel.ChannelHandler... handlers)

Method Summary

Modifier and Type	Method and Description
void	channelInactive(io.netty.channel.ChannelHandlerContext ctx) If this channel becomes inactive, then notify all buffered writes that we failed.
void	channelRegistered(io.netty.channel.ChannelHandlerContext ctx) When this channel is registered, we will add all the ChannelHandlers passed into our constructor to the pipeline.
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) Do not rely on channel handlers to propagate exceptions to us.
void	exceptionCaught(io.netty.channel.ChannelHandlerContext ctx, Throwable cause) If we encounter an exception, then notify all buffered writes that we failed.
protected void	fail(io.netty.channel.ChannelHandlerContext ctx, 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	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.
protected 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, channelRead, channelReadComplete, channelUnregistered, channelWritabilityChanged, userEventTriggered

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

ensureNotSharable, handlerAdded, handlerRemoved, isSharable

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.netty.channel.ChannelHandler

handlerAdded, handlerRemoved

Constructor Detail

AbstractBufferingHandler

protected AbstractBufferingHandler(io.netty.channel.ChannelHandler... handlers)

Parameters:

handlers - the ChannelHandlers are added to the pipeline on channelRegistered and before this handler.

Method Detail

channelRegistered

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

When this channel is registered, we will add all the ChannelHandlers passed into our constructor to the pipeline.

Specified by:

channelRegistered in interface io.netty.channel.ChannelInboundHandler

Overrides:

channelRegistered in class io.netty.channel.ChannelInboundHandlerAdapter

Throws:

Exception

connect

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

Do not rely on channel handlers to propagate exceptions to us. NettyClientHandler is an example of a class that does not propagate exceptions. Add a listener to the connect future directly and do appropriate error handling.

Specified by:

connect in interface io.netty.channel.ChannelOutboundHandler

Overrides:

connect in class io.netty.channel.ChannelDuplexHandler

Throws:

Exception

exceptionCaught

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

If we encounter an exception, then notify all buffered writes that we failed.

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

Throws:

Exception

channelInactive

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

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

Throws:

Exception

write

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

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

Throws:

Exception

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

fail

protected final void fail(io.netty.channel.ChannelHandlerContext ctx,
                          Throwable cause)

Propagate failures to all buffered writes.

writeBufferedAndRemove

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