com.rabbitmq.client.impl
Class AMQChannel

java.lang.Object
  com.rabbitmq.client.impl.AMQChannel

Direct Known Subclasses:

ChannelN

public abstract class AMQChannel
extends java.lang.Object

Base class modelling an AMQ channel. Subclasses implement close() and processAsync(), and may choose to override processShutdownSignal().

See Also:

ChannelN, Connection

Nested Class Summary

static class	AMQChannel.BlockingRpcContinuation<T>
static interface	AMQChannel.RpcContinuation
static class	AMQChannel.SimpleBlockingRpcContinuation

Field Summary

AMQChannel.RpcContinuation	_activeRpc The current outstanding RPC request, if any.
int	_channelNumber This channel's channel number.
AMQCommand.Assembler	_commandAssembler State machine assembling commands on their way in.
AMQConnection	_connection The connection this channel is associated with.
boolean	_isOpen Indicates whether this channel is in a state to handle further activity.

Constructor Summary

AMQChannel(AMQConnection connection, int channelNumber)
Construct a channel on the given connection, with the given channel number.

Method Summary

void	enqueueRpc(AMQChannel.RpcContinuation k)
void	ensureIsOpen()
AMQCommand	exnWrappingRpc(Method m) Placeholder until we address bug 15786 (implementing a proper exception hierarchy).
AMQConnection	getAMQConnection()
int	getChannelNumber() Public API - Retrieves this channel's channel number.
Connection	getConnection() Public API - Retrieves this channel's underlying connection.
void	handleCompleteInboundCommand(AMQCommand command) Private API - handle a command which has been assembled
void	handleFrame(Frame frame) Private API - When the Connection receives a Frame for this channel, it passes it to this method.
boolean	isOpen()
AMQChannel.RpcContinuation	nextOutstandingRpc()
abstract boolean	processAsync(Command command) Protected API - called by nextCommand to check possibly handle an incoming Command before it is returned to the caller of nextCommand.
void	processShutdownSignal(ShutdownSignalException signal) Protected API - respond, in the driver thread, to a ShutdownSignalException.
AMQCommand	quiescingRpc(Method m, int timeoutMillisec, AMQCommand timeoutReply) Just like rpc(Method), but for use during quiescing/close/shutdown.
AMQCommand	rpc(Method m) Protected API - sends a Command to the broker and waits for the next inbound Command from the broker: only for use from non-connection-MainLoop threads!
void	rpc(Method m, AMQChannel.RpcContinuation k)
java.lang.String	toString()
void	transmit(Method m)
void	transmitAndEnqueue(Method m, AMQChannel.RpcContinuation k)
static java.io.IOException	wrap(ShutdownSignalException ex) Placeholder until we address bug 15786 (implementing a proper exception hierarchy).

Methods inherited from class java.lang.Object

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

Field Detail

_connection

public final AMQConnection _connection

The connection this channel is associated with.

_channelNumber

public final int _channelNumber

This channel's channel number.

_commandAssembler

public AMQCommand.Assembler _commandAssembler

State machine assembling commands on their way in.

_activeRpc

public AMQChannel.RpcContinuation _activeRpc

The current outstanding RPC request, if any. (Could become a queue in future.)

_isOpen

public volatile boolean _isOpen

Indicates whether this channel is in a state to handle further activity.

Constructor Detail

AMQChannel

public AMQChannel(AMQConnection connection,
                  int channelNumber)

Construct a channel on the given connection, with the given channel number.

Parameters:

connection - the underlying connection for this channel

channelNumber - the allocated reference number for this channel

Method Detail

getChannelNumber

public int getChannelNumber()

Public API - Retrieves this channel's channel number.

Returns:

the channel number

getConnection

public Connection getConnection()

Public API - Retrieves this channel's underlying connection.

Returns:

the connection

handleFrame

public void handleFrame(Frame frame)
                 throws java.io.IOException

Private API - When the Connection receives a Frame for this channel, it passes it to this method.

Parameters:

frame - the incoming frame

Throws:

java.io.IOException - if an error is encountered

wrap

public static java.io.IOException wrap(ShutdownSignalException ex)

Placeholder until we address bug 15786 (implementing a proper exception hierarchy). In the meantime, this at least won't throw away any information from the wrapped exception.

Parameters:

ex - the exception to wrap

Returns:

the wrapped exception

exnWrappingRpc

public AMQCommand exnWrappingRpc(Method m)
                          throws java.io.IOException

Placeholder until we address bug 15786 (implementing a proper exception hierarchy).

Throws:

java.io.IOException

handleCompleteInboundCommand

public void handleCompleteInboundCommand(AMQCommand command)
                                  throws java.io.IOException

Private API - handle a command which has been assembled

Parameters:

command - the incoming command

Throws:

java.io.IOException - if there's any problem

java.io.IOException

enqueueRpc

public void enqueueRpc(AMQChannel.RpcContinuation k)

transmitAndEnqueue

public void transmitAndEnqueue(Method m,
                               AMQChannel.RpcContinuation k)
                        throws java.io.IOException

Throws:

java.io.IOException

nextOutstandingRpc

public AMQChannel.RpcContinuation nextOutstandingRpc()

isOpen

public boolean isOpen()

ensureIsOpen

public void ensureIsOpen()
                  throws java.lang.IllegalStateException

Throws:

java.lang.IllegalStateException

rpc

public AMQCommand rpc(Method m)
               throws java.io.IOException,
                      ShutdownSignalException

Protected API - sends a Command to the broker and waits for the next inbound Command from the broker: only for use from non-connection-MainLoop threads!

Throws:

java.io.IOException

ShutdownSignalException

rpc

public void rpc(Method m,
                AMQChannel.RpcContinuation k)
         throws java.io.IOException

Throws:

java.io.IOException

quiescingRpc

public AMQCommand quiescingRpc(Method m,
                               int timeoutMillisec,
                               AMQCommand timeoutReply)
                        throws java.io.IOException,
                               ShutdownSignalException

Just like rpc(Method), but for use during quiescing/close/shutdown. Not for regular use. Doesn't do the ensureIsOpen() check.

Throws:

java.io.IOException

ShutdownSignalException

processAsync

public abstract boolean processAsync(Command command)
                              throws java.io.IOException

Protected API - called by nextCommand to check possibly handle an incoming Command before it is returned to the caller of nextCommand. If this method returns true, the command is considered handled and is not passed back to nextCommand's caller; if it returns false, nextCommand returns the command as usual. This is used in subclasses to implement handling of Basic.Return and Basic.Deliver messages, as well as Channel.Close and Connection.Close.

Parameters:

command - the command to handle asynchronously

Returns:

true if we handled the command; otherwise the caller should consider it "unhandled"

Throws:

java.io.IOException

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

processShutdownSignal

public void processShutdownSignal(ShutdownSignalException signal)

Protected API - respond, in the driver thread, to a ShutdownSignalException.

Parameters:

signal - the signal to handle

transmit

public void transmit(Method m)
              throws java.io.IOException

Throws:

java.io.IOException

getAMQConnection

public AMQConnection getAMQConnection()