com.continuent.tungsten.replicator.thl
Class RemoteTHLExtractor

java.lang.Object
  com.continuent.tungsten.replicator.thl.RemoteTHLExtractor

All Implemented Interfaces:

Extractor, ReplicatorPlugin, ShutdownHook

public class RemoteTHLExtractor
extends java.lang.Object
implements Extractor, ShutdownHook

Implements an extractor to pull events from a remote THL.

This class has specialized concurrency requirements as there is a potential race condition to close connections within the task thread and thread trying to shut down the pipeline. The race arises due the fact that connections may hang when connecting or reading from a connection to a dropped interface and do not accept interrupts. They need to be interrupted by closing the connection. For this reason, closing the connection is synchronized.

Version:

1.0

Author:

Robert Hodges

Constructor Summary

RemoteTHLExtractor()
Create Connector instance.

Method Summary

void	configure(PluginContext context) Complete plug-in configuration.
ReplDBMSEvent	extract() Extract the next available event from the log.
java.util.List<java.lang.String>	getConnectUri()
java.lang.String	getCurrentResourceEventId() Does not make sense for this extractor type.
int	getHeartbeatInterval()
java.lang.String	getPreferredRole() Returns the preferred master server role.
int	getPreferredRoleTimeout()
int	getResetPeriod()
int	getRetryInterval()
boolean	hasMoreEvents() Returns true if there are additional events that may be read as part of block commit processing.
boolean	isCheckSerialization()
void	prepare(PluginContext context) Prepare plug-in for use.
void	release(PluginContext context) Release all resources used by plug-in.
void	setCheckSerialization(boolean checkSerialization) If true, check epoch number and sequence number of last event we have received.
void	setConnectUri(java.util.List<java.lang.String> connectUri) Set the URI(s) of the store to which we connect.
void	setHeartbeatInterval(int heartbeatMillis) Sets the interval for sending heartbeat events from server to avoid TCP/IP timeout on server connection.
void	setLastEvent(ReplDBMSHeader event) Set the value of the last event called.
void	setLastEventId(java.lang.String eventId) Sets the last event ID for extraction.
void	setPreferredRole(java.lang.String preferredRole) Sets the preferred role of the master replicator.
void	setPreferredRoleTimeout(int preferredRoleTimeout) Sets the timeout to find the preferred master role in seconds.
void	setResetPeriod(int resetPeriod) Set the number of iterations before resetting the communications stream.
void	setRetryInterval(int retryTimeout) Sets the timeout between connection retries in seconds.
void	shutdown(PluginContext context) Shut down component.

Methods inherited from class java.lang.Object

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

Constructor Detail

RemoteTHLExtractor

public RemoteTHLExtractor()

Create Connector instance.

Method Detail

getConnectUri

public java.util.List<java.lang.String> getConnectUri()

setConnectUri

public void setConnectUri(java.util.List<java.lang.String> connectUri)

Set the URI(s) of the store to which we connect.

Parameters:

connectUri -

getResetPeriod

public int getResetPeriod()

setResetPeriod

public void setResetPeriod(int resetPeriod)

Set the number of iterations before resetting the communications stream. Higher values use more memory but are more efficient.

isCheckSerialization

public boolean isCheckSerialization()

setCheckSerialization

public void setCheckSerialization(boolean checkSerialization)

If true, check epoch number and sequence number of last event we have received.

Parameters:

checkSerialization -

getHeartbeatInterval

public int getHeartbeatInterval()

setHeartbeatInterval

public void setHeartbeatInterval(int heartbeatMillis)

Sets the interval for sending heartbeat events from server to avoid TCP/IP timeout on server connection. The normal read timeout is 10x this value. The value is also used for connection timeouts, where we use 1x this value.

getPreferredRole

public java.lang.String getPreferredRole()

Returns the preferred master server role.

setPreferredRole

public void setPreferredRole(java.lang.String preferredRole)

Sets the preferred role of the master replicator. If set to 'slave' we will try to find a slave from the URL list before accepting a master.

getPreferredRoleTimeout

public int getPreferredRoleTimeout()

setPreferredRoleTimeout

public void setPreferredRoleTimeout(int preferredRoleTimeout)

Sets the timeout to find the preferred master role in seconds.

getRetryInterval

public int getRetryInterval()

setRetryInterval

public void setRetryInterval(int retryTimeout)

Sets the timeout between connection retries in seconds.

extract

public ReplDBMSEvent extract()
                      throws ReplicatorException,
                             java.lang.InterruptedException

Extract the next available event from the log.

Specified by:

extract in interface Extractor

Returns:

next ReplDBMSEvent found in the logs or another ReplEvent subclass containing control data

Throws:

ReplicatorException

java.lang.InterruptedException

See Also:

Extractor.extract()

getCurrentResourceEventId

public java.lang.String getCurrentResourceEventId()
                                           throws ReplicatorException,
                                                  java.lang.InterruptedException

Does not make sense for this extractor type.

Specified by:

getCurrentResourceEventId in interface Extractor

Returns:

A current event ID that can be compared with event IDs in DBMSEvent or null if this type of extractor does not extract from a database

Throws:

ReplicatorException

java.lang.InterruptedException

hasMoreEvents

public boolean hasMoreEvents()

Description copied from interface: Extractor

Returns true if there are additional events that may be read as part of block commit processing.

Specified by:

hasMoreEvents in interface Extractor

setLastEvent

public void setLastEvent(ReplDBMSHeader event)
                  throws ReplicatorException

Description copied from interface: Extractor

Set the value of the last event called. The extractor is responsible for returning the next event in sequence after this one the next time extract() is called.

Specified by:

setLastEvent in interface Extractor

Parameters:

event - Last event we extracted

Throws:

ReplicatorException

setLastEventId

public void setLastEventId(java.lang.String eventId)
                    throws ReplicatorException

Sets the last event ID for extraction. If this is set, we will request (and receive) the first event from the master log that matches this event.

Specified by:

setLastEventId in interface Extractor

Parameters:

eventId - Event ID at which to begin extracting

Throws:

ReplicatorException

See Also:

Extractor.setLastEventId(java.lang.String)

configure

public void configure(PluginContext context)
               throws ReplicatorException

Complete plug-in configuration. This is called after setters are invoked at the time that the replicator goes through configuration.

Specified by:

configure in interface ReplicatorPlugin

Throws:

ReplicatorException - Thrown if configuration is incomplete or fails

See Also:

ReplicatorPlugin.configure(com.continuent.tungsten.replicator.plugin.PluginContext)

prepare

public void prepare(PluginContext context)
             throws ReplicatorException

Prepare plug-in for use. This method is assumed to allocate all required resources. It is called before the plug-in performs any operations.

Specified by:

prepare in interface ReplicatorPlugin

Throws:

ReplicatorException - Thrown if resource allocation fails

See Also:

ReplicatorPlugin.prepare(com.continuent.tungsten.replicator.plugin.PluginContext)

release

public void release(PluginContext context)
             throws ReplicatorException

Release all resources used by plug-in. This is called before the plug-in is deallocated.

Specified by:

release in interface ReplicatorPlugin

Throws:

ReplicatorException - Thrown if resource deallocation fails

See Also:

ReplicatorPlugin.release(com.continuent.tungsten.replicator.plugin.PluginContext)

shutdown

public void shutdown(PluginContext context)
              throws ReplicatorException,
                     java.lang.InterruptedException

Shut down component. This is called after the task interrupt and should ensure the component responds correctly to an interrupt.

Specified by:

shutdown in interface ShutdownHook

Throws:

ReplicatorException - Thrown if shutdown is unsuccessful

java.lang.InterruptedException

See Also:

ShutdownHook.shutdown(com.continuent.tungsten.replicator.plugin.PluginContext)