org.apache.catalina.tribes.transport.nio

Class NioReplicationTask

java.lang.Object

org.apache.catalina.tribes.transport.AbstractRxTask

org.apache.catalina.tribes.transport.nio.NioReplicationTask

All Implemented Interfaces:

Runnable

public class NioReplicationTask
extends AbstractRxTask

A worker thread class which can drain channels and echo-back the input. Each instance is constructed with a reference to the owning thread pool object. When started, the thread loops forever waiting to be awakened to service the channel associated with a SelectionKey object. The worker is tasked by calling its serviceChannel() method with a SelectionKey object. The serviceChannel() method stores the key reference in the thread object then calls notify() to wake it up. When the channel has been drained, the worker thread returns itself to its parent pool.

Field Summary

Fields

Modifier and Type	Field and Description
protected static StringManager	sm

Fields inherited from class org.apache.catalina.tribes.transport.AbstractRxTask

OPTION_DIRECT_BUFFER, useBufferPool

Constructor Summary

Constructors

Constructor and Description
NioReplicationTask(ListenCallback callback, NioReceiver receiver)

Method Summary

Modifier and Type	Method and Description
protected void	drainChannel(SelectionKey key, ObjectReader reader) The actual code which drains the channel associated with the given key.
int	getRxBufSize()
protected void	registerForRead(SelectionKey key, ObjectReader reader)
void	run()
protected void	sendAck(SelectionKey key, WritableByteChannel channel, byte[] command, SocketAddress udpaddr) Send a reply-acknowledgement (6,2,3), sends it doing a busy write, the ACK is so small that it should always go to the buffer.
void	serviceChannel(SelectionKey key) Called to initiate a unit of work by this worker thread on the provided SelectionKey object.
void	setRxBufSize(int rxBufSize)

Methods inherited from class org.apache.catalina.tribes.transport.AbstractRxTask

close, getCallback, getOptions, getTaskPool, getUseBufferPool, isDoRun, setCallback, setDoRun, setOptions, setTaskPool, setUseBufferPool

Methods inherited from class java.lang.Object

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

Field Detail

sm

protected static final StringManager sm

Constructor Detail

NioReplicationTask

public NioReplicationTask(ListenCallback callback,
                          NioReceiver receiver)

Method Detail

run

public void run()

serviceChannel

public void serviceChannel(SelectionKey key)

Called to initiate a unit of work by this worker thread on the provided SelectionKey object. This method is synchronized, as is the run() method, so only one key can be serviced at a given time. Before waking the worker thread, and before returning to the main selection loop, this key's interest set is updated to remove OP_READ. This will cause the selector to ignore read-readiness for this channel while the worker thread is servicing it.

Parameters:

key - The key to process

drainChannel

protected void drainChannel(SelectionKey key,
                            ObjectReader reader)
                     throws Exception

The actual code which drains the channel associated with the given key. This method assumes the key has been modified prior to invocation to turn off selection interest in OP_READ. When this method completes it re-enables OP_READ and calls wakeup() on the selector so the selector will resume watching this channel.

Parameters:

key - The key to process

reader - The reader

Throws:

Exception - IO error

registerForRead

protected void registerForRead(SelectionKey key,
                               ObjectReader reader)

sendAck

protected void sendAck(SelectionKey key,
                       WritableByteChannel channel,
                       byte[] command,
                       SocketAddress udpaddr)

Send a reply-acknowledgement (6,2,3), sends it doing a busy write, the ACK is so small that it should always go to the buffer.

Parameters:

key - The key to use

channel - The channel

command - The command to write

udpaddr - Target address

setRxBufSize

public void setRxBufSize(int rxBufSize)

getRxBufSize

public int getRxBufSize()