com.hazelcast.internal.networking

Class ChannelHandler<H extends ChannelHandler,S,D>

java.lang.Object

com.hazelcast.internal.networking.ChannelHandler<H,S,D>

Type Parameters:

S - the type of the source. E.g. a ByteBuffer or a Supplier.

D - the type of the destination. E.g. a ByteBuffer or a Consumer.

Direct Known Subclasses:

InboundHandler, OutboundHandler

public abstract class ChannelHandler<H extends ChannelHandler,S,D>
extends Object

ChannelHandler is either responsible for processing inbound or outbound data. ChannelHandlers are not expected to be thread-safe.

Field Summary

Fields

Modifier and Type	Field and Description
protected Channel	channel The Channel this ChannelHandler handles.
protected D	dst
protected S	src

Constructor Summary

Constructors

Constructor and Description
ChannelHandler()

Method Summary

Modifier and Type	Method and Description
D	dst() Gets the destination of this ChannelHandler.
void	dst(D dst) Sets the destination of this ChannelHandler.
void	handlerAdded() Gets called when this ChannelHandler is added to the pipeline.
void	interceptError(Throwable error) Intercepts an error that is thrown while processing the inbound or outbound pipeline.
void	requestClose() Asks handler to trigger the closing process.
H	setChannel(Channel channel) Sets the Channel.
S	src() Gets the source of this ChannelHandler.
void	src(S src) Sets the source of this ChannelHandler.

Methods inherited from class java.lang.Object

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

Field Detail

channel

protected Channel channel

The Channel this ChannelHandler handles. Only the owning pipeline should modify this field.

src

protected S src

dst

protected D dst

Constructor Detail

ChannelHandler

public ChannelHandler()

Method Detail

src

public S src()

Gets the source of this ChannelHandler. This method should only be called from the thread that owns this ChannelHandler.

Returns:

the source; could be null.

src

public void src(S src)

Sets the source of this ChannelHandler. This method should only be called from the thread that owns this ChannelHandler.

Parameters:

src - the new source; is allowed to be null.

dst

public D dst()

Gets the destination of this ChannelHandler. This method should only be called from the thread that owns this ChannelHandler.

Returns:

the destination; could be null.

dst

public void dst(D dst)

Sets the destination of this ChannelHandler. This method should only be called from the thread that owns this ChannelHandler.

Parameters:

dst - the new destination; is allowed to be null.

setChannel

public final H setChannel(Channel channel)

Sets the Channel. Should only be called by the InboundPipeline.

Parameters:

channel - the Channel

Returns:

this instance

handlerAdded

public void handlerAdded()

Gets called when this ChannelHandler is added to the pipeline. This method should execute very quickly because it could be executed on an io thread. Will be called from a thread owning this handler.

interceptError

public void interceptError(Throwable error)
                    throws Throwable

Intercepts an error that is thrown while processing the inbound or outbound pipeline. The default implementation doesn't do anything and the original Throwable is send to the ChannelErrorHandler. However in some cases like with TLS a more informative exception needs to be thrown. To prevent loosing stacktraces, it is best to include the original Throwable as cause in the new Throwable. This method will only be called from the thread owning the pipeline this handler is part of. No modifications should be done to the pipeline and no attempts should be made to 'repair' the channel. When a Throwable is thrown, it is the end of the channel.

Parameters:

error - the Throwable thrown while processing the pipeline.

Throws:

Throwable - the new Throwable

requestClose

public void requestClose()
                  throws Exception

Asks handler to trigger the closing process. Only has meaning currently for TLS. Probably this method will be replaced by some kind of general purpose event handler. An event can be thrown in the pipeline and will be pushed through each handler and it is up to the handler to respond (or not). SO we could have a close event, but also other events like handlers sending messages to each other which requires custom exchange logic currently.

Throws:

Exception