Package io.netty.handler.proxy

Class ProxyHandler

java.lang.Object

io.netty.channel.ChannelHandlerAdapter

io.netty.channel.ChannelInboundHandlerAdapter

io.netty.channel.ChannelDuplexHandler

io.netty.handler.proxy.ProxyHandler

All Implemented Interfaces:

ChannelHandler, ChannelInboundHandler, ChannelOutboundHandler

Direct Known Subclasses:

HttpProxyHandler, Socks4ProxyHandler, Socks5ProxyHandler

public abstract class ProxyHandler
extends ChannelDuplexHandler

A common abstraction for protocols that establish blind forwarding proxy tunnels.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private final class	ProxyHandler.LazyChannelPromise

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

ChannelHandler.Sharable

Field Summary

Fields

Modifier and Type	Field	Description
(package private) static final String	AUTH_NONE	A string that signifies 'no authentication' or 'anonymous'.
private final ProxyHandler.LazyChannelPromise	connectPromise
private Future<?>	connectTimeoutFuture
private long	connectTimeoutMillis
private ChannelHandlerContext	ctx
private static final long	DEFAULT_CONNECT_TIMEOUT_MILLIS	The default connect timeout: 10 seconds.
private SocketAddress	destinationAddress
private boolean	finished
private boolean	flushedPrematurely
private static final InternalLogger	logger
private PendingWriteQueue	pendingWrites
private final SocketAddress	proxyAddress
private boolean	suppressChannelReadComplete
private final ChannelFutureListener	writeListener

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ProxyHandler(SocketAddress proxyAddress)

Method Summary

Modifier and Type	Method	Description
protected abstract void	addCodec(ChannelHandlerContext ctx)	Adds the codec handlers required to communicate with the proxy server.
private void	addPendingWrite(ChannelHandlerContext ctx, Object msg, ChannelPromise promise)
abstract String	authScheme()	Returns the name of the authentication scheme in use.
private void	cancelConnectTimeoutFuture()
final void	channelActive(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelActive() to forward to the next ChannelInboundHandler in the ChannelPipeline.
final void	channelInactive(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelInactive() to forward to the next ChannelInboundHandler in the ChannelPipeline.
final void	channelRead(ChannelHandlerContext ctx, Object msg)	Calls ChannelHandlerContext.fireChannelRead(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline.
final void	channelReadComplete(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.fireChannelReadComplete() to forward to the next ChannelInboundHandler in the ChannelPipeline.
final void	connect(ChannelHandlerContext ctx, SocketAddress remoteAddress, SocketAddress localAddress, ChannelPromise promise)	Calls ChannelOutboundInvoker.connect(SocketAddress, SocketAddress, ChannelPromise) to forward to the next ChannelOutboundHandler in the ChannelPipeline.
final Future<Channel>	connectFuture()	Returns a Future that is notified when the connection to the destination has been established or the connection attempt has failed.
final long	connectTimeoutMillis()	Returns the connect timeout in millis.
final <T extends SocketAddress> T	destinationAddress()	Returns the address of the destination to connect to via the proxy server.
final void	exceptionCaught(ChannelHandlerContext ctx, Throwable cause)	Calls ChannelHandlerContext.fireExceptionCaught(Throwable) to forward to the next ChannelHandler in the ChannelPipeline.
protected final String	exceptionMessage(String msg)	Decorates the specified exception message with the common information such as the current protocol, authentication scheme, proxy address, and destination address.
private void	failPendingWrites(Throwable cause)
private void	failPendingWritesAndClose(Throwable cause)
final void	flush(ChannelHandlerContext ctx)	Calls ChannelHandlerContext.flush() to forward to the next ChannelOutboundHandler in the ChannelPipeline.
final void	handlerAdded(ChannelHandlerContext ctx)	Do nothing by default, sub-classes may override this method.
protected abstract boolean	handleResponse(ChannelHandlerContext ctx, Object response)	Handles the message received from the proxy server.
final boolean	isConnected()	Returns true if and only if the connection to the destination has been established successfully.
protected abstract Object	newInitialMessage(ChannelHandlerContext ctx)	Returns a new message that is sent at first time when the connection to the proxy server has been established.
abstract String	protocol()	Returns the name of the proxy protocol in use.
final <T extends SocketAddress> T	proxyAddress()	Returns the address of the proxy server.
private static void	readIfNeeded(ChannelHandlerContext ctx)
protected abstract void	removeDecoder(ChannelHandlerContext ctx)	Removes the decoders added in addCodec(ChannelHandlerContext).
protected abstract void	removeEncoder(ChannelHandlerContext ctx)	Removes the encoders added in addCodec(ChannelHandlerContext).
private boolean	safeRemoveDecoder()
private boolean	safeRemoveEncoder()
private void	sendInitialMessage(ChannelHandlerContext ctx)	Sends the initial message to be sent to the proxy server.
protected final void	sendToProxyServer(Object msg)	Sends the specified message to the proxy server.
private void	setConnectFailure(Throwable cause)
private void	setConnectSuccess()
final void	setConnectTimeoutMillis(long connectTimeoutMillis)	Sets the connect timeout in millis.
final void	write(ChannelHandlerContext ctx, Object msg, ChannelPromise promise)	Calls ChannelOutboundInvoker.write(Object, ChannelPromise) to forward to the next ChannelOutboundHandler in the ChannelPipeline.
private void	writePendingWrites()

Methods inherited from class io.netty.channel.ChannelDuplexHandler

bind, close, deregister, disconnect, read

Methods inherited from class io.netty.channel.ChannelInboundHandlerAdapter

channelRegistered, channelUnregistered, channelWritabilityChanged, userEventTriggered

Methods inherited from class io.netty.channel.ChannelHandlerAdapter

ensureNotSharable, 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

handlerRemoved

Field Details

logger

private static final InternalLogger logger

DEFAULT_CONNECT_TIMEOUT_MILLIS

private static final long DEFAULT_CONNECT_TIMEOUT_MILLIS

The default connect timeout: 10 seconds.

See Also:

• Constant Field Values

AUTH_NONE

static final String AUTH_NONE

A string that signifies 'no authentication' or 'anonymous'.

See Also:

• Constant Field Values

proxyAddress

private final SocketAddress proxyAddress

destinationAddress

private volatile SocketAddress destinationAddress

connectTimeoutMillis

private volatile long connectTimeoutMillis

ctx

private volatile ChannelHandlerContext ctx

pendingWrites

private PendingWriteQueue pendingWrites

finished

private boolean finished

suppressChannelReadComplete

private boolean suppressChannelReadComplete

flushedPrematurely

private boolean flushedPrematurely

connectPromise

private final ProxyHandler.LazyChannelPromise connectPromise

connectTimeoutFuture

private Future<?> connectTimeoutFuture

writeListener

private final ChannelFutureListener writeListener

Constructor Details

ProxyHandler

protected ProxyHandler(SocketAddress proxyAddress)

Method Details

protocol

public abstract String protocol()

Returns the name of the proxy protocol in use.

authScheme

public abstract String authScheme()

Returns the name of the authentication scheme in use.

proxyAddress

public final <T extends SocketAddress> T proxyAddress()

Returns the address of the proxy server.

destinationAddress

public final <T extends SocketAddress> T destinationAddress()

Returns the address of the destination to connect to via the proxy server.

isConnected

public final boolean isConnected()

Returns true if and only if the connection to the destination has been established successfully.

connectFuture

public final Future<Channel> connectFuture()

Returns a Future that is notified when the connection to the destination has been established or the connection attempt has failed.

connectTimeoutMillis

public final long connectTimeoutMillis()

Returns the connect timeout in millis. If the connection attempt to the destination does not finish within the timeout, the connection attempt will be failed.

setConnectTimeoutMillis

public final void setConnectTimeoutMillis(long connectTimeoutMillis)

Sets the connect timeout in millis. If the connection attempt to the destination does not finish within the timeout, the connection attempt will be failed.

handlerAdded

public final void handlerAdded(ChannelHandlerContext ctx)
                        throws Exception

Description copied from class: ChannelHandlerAdapter

Do nothing by default, sub-classes may override this method.

Specified by:

handlerAdded in interface ChannelHandler

Overrides:

handlerAdded in class ChannelHandlerAdapter

Throws:

Exception

addCodec

protected abstract void addCodec(ChannelHandlerContext ctx)
                          throws Exception

Adds the codec handlers required to communicate with the proxy server.

Throws:

Exception

removeEncoder

protected abstract void removeEncoder(ChannelHandlerContext ctx)
                               throws Exception

Removes the encoders added in addCodec(ChannelHandlerContext).

Throws:

Exception

removeDecoder

protected abstract void removeDecoder(ChannelHandlerContext ctx)
                               throws Exception

Removes the decoders added in addCodec(ChannelHandlerContext).

Throws:

Exception

connect

public final void connect(ChannelHandlerContext ctx,
 SocketAddress remoteAddress,
 SocketAddress localAddress,
 ChannelPromise promise)
                   throws Exception

Description copied from class: ChannelDuplexHandler

Calls ChannelOutboundInvoker.connect(SocketAddress, SocketAddress, ChannelPromise) to forward to the next ChannelOutboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

connect in interface ChannelOutboundHandler

Overrides:

connect in class ChannelDuplexHandler

Parameters:

ctx - the ChannelHandlerContext for which the connect operation is made

remoteAddress - the SocketAddress to which it should connect

localAddress - the SocketAddress which is used as source on connect

promise - the ChannelPromise to notify once the operation completes

Throws:

Exception - thrown if an error occurs

channelActive

public final void channelActive(ChannelHandlerContext ctx)
                         throws Exception

Description copied from class: ChannelInboundHandlerAdapter

Calls ChannelHandlerContext.fireChannelActive() to forward to the next ChannelInboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

channelActive in interface ChannelInboundHandler

Overrides:

channelActive in class ChannelInboundHandlerAdapter

Throws:

Exception

sendInitialMessage

private void sendInitialMessage(ChannelHandlerContext ctx)
                         throws Exception

Sends the initial message to be sent to the proxy server. This method also starts a timeout task which marks the connectPromise as failure if the connection attempt does not success within the timeout.

Throws:

Exception

newInitialMessage

protected abstract Object newInitialMessage(ChannelHandlerContext ctx)
                                     throws Exception

Returns a new message that is sent at first time when the connection to the proxy server has been established.

Returns:

the initial message, or null if the proxy server is expected to send the first message instead

Throws:

Exception

sendToProxyServer

protected final void sendToProxyServer(Object msg)

Sends the specified message to the proxy server. Use this method to send a response to the proxy server in handleResponse(ChannelHandlerContext, Object).

channelInactive

public final void channelInactive(ChannelHandlerContext ctx)
                           throws Exception

Description copied from class: ChannelInboundHandlerAdapter

Calls ChannelHandlerContext.fireChannelInactive() to forward to the next ChannelInboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

channelInactive in interface ChannelInboundHandler

Overrides:

channelInactive in class ChannelInboundHandlerAdapter

Throws:

Exception

exceptionCaught

public final void exceptionCaught(ChannelHandlerContext ctx,
 Throwable cause)
                           throws Exception

Description copied from class: ChannelInboundHandlerAdapter

Calls ChannelHandlerContext.fireExceptionCaught(Throwable) to forward to the next ChannelHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

exceptionCaught in interface ChannelHandler

Specified by:

exceptionCaught in interface ChannelInboundHandler

Overrides:

exceptionCaught in class ChannelInboundHandlerAdapter

Throws:

Exception

channelRead

public final void channelRead(ChannelHandlerContext ctx,
 Object msg)
                       throws Exception

Description copied from class: ChannelInboundHandlerAdapter

Calls ChannelHandlerContext.fireChannelRead(Object) to forward to the next ChannelInboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

channelRead in interface ChannelInboundHandler

Overrides:

channelRead in class ChannelInboundHandlerAdapter

Throws:

Exception

handleResponse

protected abstract boolean handleResponse(ChannelHandlerContext ctx,
 Object response)
                                   throws Exception

Handles the message received from the proxy server.

Returns:

true if the connection to the destination has been established, false if the connection to the destination has not been established and more messages are expected from the proxy server

Throws:

Exception

setConnectSuccess

private void setConnectSuccess()

safeRemoveDecoder

private boolean safeRemoveDecoder()

safeRemoveEncoder

private boolean safeRemoveEncoder()

setConnectFailure

private void setConnectFailure(Throwable cause)

failPendingWritesAndClose

private void failPendingWritesAndClose(Throwable cause)

cancelConnectTimeoutFuture

private void cancelConnectTimeoutFuture()

exceptionMessage

protected final String exceptionMessage(String msg)

Decorates the specified exception message with the common information such as the current protocol, authentication scheme, proxy address, and destination address.

channelReadComplete

public final void channelReadComplete(ChannelHandlerContext ctx)
                               throws Exception

Description copied from class: ChannelInboundHandlerAdapter

Calls ChannelHandlerContext.fireChannelReadComplete() to forward to the next ChannelInboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

channelReadComplete in interface ChannelInboundHandler

Overrides:

channelReadComplete in class ChannelInboundHandlerAdapter

Throws:

Exception

write

public final void write(ChannelHandlerContext ctx,
 Object msg,
 ChannelPromise promise)
                 throws Exception

Description copied from class: ChannelDuplexHandler

Calls ChannelOutboundInvoker.write(Object, ChannelPromise) to forward to the next ChannelOutboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

write in interface ChannelOutboundHandler

Overrides:

write in class ChannelDuplexHandler

Parameters:

ctx - the ChannelHandlerContext for which the write operation is made

msg - the message to write

promise - the ChannelPromise to notify once the operation completes

Throws:

Exception - thrown if an error occurs

flush

public final void flush(ChannelHandlerContext ctx)
                 throws Exception

Description copied from class: ChannelDuplexHandler

Calls ChannelHandlerContext.flush() to forward to the next ChannelOutboundHandler in the ChannelPipeline. Sub-classes may override this method to change behavior.

Specified by:

flush in interface ChannelOutboundHandler

Overrides:

flush in class ChannelDuplexHandler

Parameters:

ctx - the ChannelHandlerContext for which the flush operation is made

Throws:

Exception - thrown if an error occurs

readIfNeeded

private static void readIfNeeded(ChannelHandlerContext ctx)

writePendingWrites

private void writePendingWrites()

failPendingWrites

private void failPendingWrites(Throwable cause)

addPendingWrite

private void addPendingWrite(ChannelHandlerContext ctx,
 Object msg,
 ChannelPromise promise)