Package io.debezium.connector.oracle.xstream

Class XstreamStreamingChangeEventSource

java.lang.Object

io.debezium.connector.oracle.xstream.XstreamStreamingChangeEventSource

All Implemented Interfaces:

ChangeEventSource, StreamingChangeEventSource<OraclePartition,OracleOffsetContext>

public class XstreamStreamingChangeEventSource
extends Object
implements StreamingChangeEventSource<OraclePartition,OracleOffsetContext>

A StreamingChangeEventSource based on Oracle's XStream API. The XStream event handler loop is executed in a separate executor.

Author:

Gunnar Morling

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	XstreamStreamingChangeEventSource.PositionAndScn

Nested classes/interfaces inherited from interface io.debezium.pipeline.source.spi.ChangeEventSource

ChangeEventSource.ChangeEventSourceContext

Field Summary

Fields

Modifier and Type	Field	Description
private final DelayStrategy	attachRetryStrategy
private final Clock	clock
private final OracleConnectorConfig	connectorConfig
private static final int	DEFAULT_MAX_ATTACH_RETRIES
private static final int	DEFAULT_MAX_ATTACH_RETRY_DELAY_SECONDS
private final EventDispatcher<OraclePartition,TableId>	dispatcher
private OracleOffsetContext	effectiveOffset
private final ErrorHandler	errorHandler
private final OracleConnection	jdbcConnection
private final AtomicReference<XstreamStreamingChangeEventSource.PositionAndScn>	lcrMessage	A message box between thread that is informed about committed offsets and the XStream thread.
private static final org.slf4j.Logger	LOGGER
private final int	posVersion
private final OracleDatabaseSchema	schema
private final XStreamStreamingChangeEventSourceMetrics	streamingMetrics
private oracle.streams.XStreamOut	xsOut
private final String	xStreamServerName

Constructor Summary

Constructors

Constructor	Description
XstreamStreamingChangeEventSource(OracleConnectorConfig connectorConfig, OracleConnection jdbcConnection, EventDispatcher<OraclePartition,TableId> dispatcher, ErrorHandler errorHandler, Clock clock, OracleDatabaseSchema schema, XStreamStreamingChangeEventSourceMetrics streamingMetrics)

Method Summary

Modifier and Type	Method	Description
void	commitOffset(Map<String,?> partition, Map<String,?> offset)
private byte[]	convertScnToPosition(Scn scn)
private OracleOffsetContext	emptyContext()
void	execute(ChangeEventSource.ChangeEventSourceContext context, OraclePartition partition, OracleOffsetContext offsetContext)
OracleOffsetContext	getOffsetContext()
(package private) oracle.streams.XStreamOut	getXsOut()
void	init(OracleOffsetContext offsetContext)
private boolean	isAttachExceptionRetriable(oracle.streams.StreamsException e)
private oracle.streams.XStreamOut	performAttachWithRetries(OracleConnection xsConnection, byte[] startPosition)
(package private) XstreamStreamingChangeEventSource.PositionAndScn	receivePublishedPosition()
private static int	resolvePosVersion(OracleConnection connection, OracleConnectorConfig connectorConfig)
private void	sendPublishedPosition(LcrPosition lcrPosition, Scn scn)

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.debezium.pipeline.source.spi.StreamingChangeEventSource

executeIteration

Field Details

LOGGER

private static final org.slf4j.Logger LOGGER

DEFAULT_MAX_ATTACH_RETRIES

private static final int DEFAULT_MAX_ATTACH_RETRIES

See Also:

• Constant Field Values

DEFAULT_MAX_ATTACH_RETRY_DELAY_SECONDS

private static final int DEFAULT_MAX_ATTACH_RETRY_DELAY_SECONDS

See Also:

• Constant Field Values

connectorConfig

private final OracleConnectorConfig connectorConfig

jdbcConnection

private final OracleConnection jdbcConnection

dispatcher

private final EventDispatcher<OraclePartition,TableId> dispatcher

errorHandler

private final ErrorHandler errorHandler

clock

private final Clock clock

schema

private final OracleDatabaseSchema schema

streamingMetrics

private final XStreamStreamingChangeEventSourceMetrics streamingMetrics

xStreamServerName

private final String xStreamServerName

xsOut

private volatile oracle.streams.XStreamOut xsOut

posVersion

private final int posVersion

lcrMessage

private final AtomicReference<XstreamStreamingChangeEventSource.PositionAndScn> lcrMessage

A message box between thread that is informed about committed offsets and the XStream thread. When the last offset is committed its value is passed to the XStream thread and a watermark is set to signal which events were safely processed. This is important as setting watermark in a concurrent thread can lead to a deadlock due to an internal Oracle code locking.

attachRetryStrategy

private final DelayStrategy attachRetryStrategy

effectiveOffset

private OracleOffsetContext effectiveOffset

Constructor Details

XstreamStreamingChangeEventSource

public XstreamStreamingChangeEventSource(OracleConnectorConfig connectorConfig,
 OracleConnection jdbcConnection,
 EventDispatcher<OraclePartition,TableId> dispatcher,
 ErrorHandler errorHandler,
 Clock clock,
 OracleDatabaseSchema schema,
 XStreamStreamingChangeEventSourceMetrics streamingMetrics)

Method Details

init

public void init(OracleOffsetContext offsetContext)
          throws InterruptedException

Specified by:

init in interface StreamingChangeEventSource<OraclePartition,OracleOffsetContext>

Throws:

InterruptedException

emptyContext

private OracleOffsetContext emptyContext()

execute

public void execute(ChangeEventSource.ChangeEventSourceContext context,
 OraclePartition partition,
 OracleOffsetContext offsetContext)
             throws InterruptedException

Specified by:

execute in interface StreamingChangeEventSource<OraclePartition,OracleOffsetContext>

Throws:

InterruptedException

commitOffset

public void commitOffset(Map<String,?> partition,
 Map<String,?> offset)

Specified by:

commitOffset in interface StreamingChangeEventSource<OraclePartition,OracleOffsetContext>

getOffsetContext

public OracleOffsetContext getOffsetContext()

Specified by:

getOffsetContext in interface StreamingChangeEventSource<OraclePartition,OracleOffsetContext>

performAttachWithRetries

private oracle.streams.XStreamOut performAttachWithRetries(OracleConnection xsConnection,
 byte[] startPosition)
                                                    throws Exception

Throws:

Exception

isAttachExceptionRetriable

private boolean isAttachExceptionRetriable(oracle.streams.StreamsException e)

convertScnToPosition

private byte[] convertScnToPosition(Scn scn)

getXsOut

oracle.streams.XStreamOut getXsOut()

sendPublishedPosition

private void sendPublishedPosition(LcrPosition lcrPosition,
 Scn scn)

receivePublishedPosition

XstreamStreamingChangeEventSource.PositionAndScn receivePublishedPosition()

resolvePosVersion

private static int resolvePosVersion(OracleConnection connection,
 OracleConnectorConfig connectorConfig)