Package org.apache.activemq.broker.region.cursors

Class AbstractPendingMessageCursor

java.lang.Object

org.apache.activemq.broker.region.cursors.AbstractPendingMessageCursor

All Implemented Interfaces:

PendingMessageCursor, org.apache.activemq.Service

Direct Known Subclasses:

AbstractStoreCursor, FilePendingMessageCursor, StoreDurableSubscriberCursor, StoreQueueCursor, VMPendingMessageCursor

public abstract class AbstractPendingMessageCursor
extends Object
implements PendingMessageCursor

Abstract method holder for pending message (messages awaiting disptach to a consumer) cursor

Field Summary

Fields

Modifier and Type	Field	Description
protected org.apache.activemq.ActiveMQMessageAudit	audit
protected boolean	cacheEnabled
protected boolean	enableAudit
protected org.apache.activemq.broker.region.MessageReference	last
protected int	maxAuditDepth
protected int	maxBatchSize
protected int	maxProducersToAudit
protected int	memoryUsageHighWaterMark
protected final boolean	prioritizedMessages
protected boolean	started
protected SystemUsage	systemUsage
protected boolean	useCache

Fields inherited from interface org.apache.activemq.broker.region.cursors.PendingMessageCursor

INFINITE_WAIT

Constructor Summary

Constructors

Constructor	Description
AbstractPendingMessageCursor(boolean prioritizedMessages)

Method Summary

Modifier and Type	Method	Description
void	add(ConnectionContext context, Destination destination)	Add a destination
void	addMessageFirst(org.apache.activemq.broker.region.MessageReference node)	add message to await dispatch
boolean	addMessageLast(org.apache.activemq.broker.region.MessageReference node)	add message to await dispatch
void	addRecoveredMessage(org.apache.activemq.broker.region.MessageReference node)	Add a message recovered from a retroactive policy
void	clear()	clear all pending messages
void	destroy()	destroy the cursor
protected void	fillBatch()
void	gc()	free up any internal buffers
int	getMaxAuditDepth()
int	getMaxBatchSize()
int	getMaxProducersToAudit()
int	getMemoryUsageHighWaterMark()
org.apache.activemq.ActiveMQMessageAudit	getMessageAudit()
SystemUsage	getSystemUsage()
boolean	hasMessagesBufferedToDeliver()
boolean	hasNext()
boolean	hasSpace()
boolean	isCacheEnabled()
boolean	isDuplicate(org.apache.activemq.command.MessageId messageId)
boolean	isEmpty()
boolean	isEmpty(Destination destination)	check if a Destination is Empty for this cursor
boolean	isEnableAudit()
boolean	isFull()
static boolean	isPrioritizedMessageSubscriber(Broker broker, Subscription sub)
boolean	isRecoveryRequired()	Informs the Broker if the subscription needs to intervention to recover it's state e.g.
boolean	isStarted()
boolean	isTransient()
boolean	isUseCache()
org.apache.activemq.broker.region.MessageReference	next()
LinkedList<org.apache.activemq.broker.region.MessageReference>	pageInList(int maxItems)	Page in a restricted number of messages
void	rebase()
boolean	recordUniqueId(org.apache.activemq.command.MessageId messageId)	records a message id and checks if it is a duplicate
void	release()	hint to the cursor to release any locks it might have grabbed after a reset
void	remove()	remove the message at the cursor position
List<org.apache.activemq.broker.region.MessageReference>	remove(ConnectionContext context, Destination destination)	remove a destination
void	remove(org.apache.activemq.broker.region.MessageReference node)	remove a node
void	reset()	reset the cursor
void	resetForGC()	Give the cursor a hint that we are about to remove messages from memory only
void	rollback(org.apache.activemq.command.MessageId id)	remove from auditing the message id
void	setCacheEnabled(boolean val)
void	setEnableAudit(boolean enableAudit)
void	setMaxAuditDepth(int maxAuditDepth)	Set the maximum depth of message ids to track
void	setMaxBatchSize(int maxBatchSize)	Set the max batch size
void	setMaxProducersToAudit(int maxProducersToAudit)	set the maximum number of producers to track at one time
void	setMemoryUsageHighWaterMark(int memoryUsageHighWaterMark)
void	setMessageAudit(org.apache.activemq.ActiveMQMessageAudit audit)	set the audit
void	setSystemUsage(SystemUsage usageManager)	Set the UsageManager
void	setUseCache(boolean useCache)	use a cache to improve performance
int	size()
void	start()
void	stop()
boolean	tryAddMessageLast(org.apache.activemq.broker.region.MessageReference node, long maxWaitTime)	add message to await dispatch - if it can

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.activemq.broker.region.cursors.PendingMessageCursor

messageSize

Field Details

memoryUsageHighWaterMark

protected int memoryUsageHighWaterMark

maxBatchSize

protected int maxBatchSize

systemUsage

protected SystemUsage systemUsage

maxProducersToAudit

protected int maxProducersToAudit

maxAuditDepth

protected int maxAuditDepth

enableAudit

protected boolean enableAudit

audit

protected org.apache.activemq.ActiveMQMessageAudit audit

useCache

protected boolean useCache

cacheEnabled

protected boolean cacheEnabled

started

protected boolean started

last

protected org.apache.activemq.broker.region.MessageReference last

prioritizedMessages

protected final boolean prioritizedMessages

Constructor Details

AbstractPendingMessageCursor

public AbstractPendingMessageCursor(boolean prioritizedMessages)

Method Details

start

public void start()
           throws Exception

Specified by:

start in interface org.apache.activemq.Service

Throws:

Exception

stop

public void stop()
          throws Exception

Specified by:

stop in interface org.apache.activemq.Service

Throws:

Exception

add

public void add(ConnectionContext context,
 Destination destination)
         throws Exception

Description copied from interface: PendingMessageCursor

Add a destination

Specified by:

add in interface PendingMessageCursor

Throws:

Exception

remove

public List<org.apache.activemq.broker.region.MessageReference> remove(ConnectionContext context,
 Destination destination)
                                                                throws Exception

Description copied from interface: PendingMessageCursor

remove a destination

Specified by:

remove in interface PendingMessageCursor

Throws:

Exception

isRecoveryRequired

public boolean isRecoveryRequired()

Description copied from interface: PendingMessageCursor

Informs the Broker if the subscription needs to intervention to recover it's state e.g. DurableTopicSubscriber may do

Specified by:

isRecoveryRequired in interface PendingMessageCursor

Returns:

true if recovery required

addMessageFirst

public void addMessageFirst(org.apache.activemq.broker.region.MessageReference node)
                     throws Exception

Description copied from interface: PendingMessageCursor

add message to await dispatch

Specified by:

addMessageFirst in interface PendingMessageCursor

Throws:

Exception

addMessageLast

public boolean addMessageLast(org.apache.activemq.broker.region.MessageReference node)
                       throws Exception

Description copied from interface: PendingMessageCursor

add message to await dispatch

Specified by:

addMessageLast in interface PendingMessageCursor

Returns:

boolean true if successful, false if cursor traps a duplicate

Throws:

IOException

Exception

tryAddMessageLast

public boolean tryAddMessageLast(org.apache.activemq.broker.region.MessageReference node,
 long maxWaitTime)
                          throws Exception

Description copied from interface: PendingMessageCursor

add message to await dispatch - if it can

Specified by:

tryAddMessageLast in interface PendingMessageCursor

Returns:

true if successful

Throws:

IOException

Exception

addRecoveredMessage

public void addRecoveredMessage(org.apache.activemq.broker.region.MessageReference node)
                         throws Exception

Description copied from interface: PendingMessageCursor

Add a message recovered from a retroactive policy

Specified by:

addRecoveredMessage in interface PendingMessageCursor

Throws:

Exception

clear

public void clear()

Description copied from interface: PendingMessageCursor

clear all pending messages

Specified by:

clear in interface PendingMessageCursor

hasNext

public boolean hasNext()

Specified by:

hasNext in interface PendingMessageCursor

Returns:

true if there pending messages to dispatch

isEmpty

public boolean isEmpty()

Specified by:

isEmpty in interface PendingMessageCursor

Returns:

true if there are no pending messages

isEmpty

public boolean isEmpty(Destination destination)

Description copied from interface: PendingMessageCursor

check if a Destination is Empty for this cursor

Specified by:

isEmpty in interface PendingMessageCursor

Returns:

true id the Destination is empty

next

public org.apache.activemq.broker.region.MessageReference next()

Specified by:

next in interface PendingMessageCursor

Returns:

the next pending message with its reference count increment

remove

public void remove()

Description copied from interface: PendingMessageCursor

remove the message at the cursor position

Specified by:

remove in interface PendingMessageCursor

reset

public void reset()

Description copied from interface: PendingMessageCursor

reset the cursor

Specified by:

reset in interface PendingMessageCursor

size

public int size()

Specified by:

size in interface PendingMessageCursor

Returns:

the number of pending messages

getMaxBatchSize

public int getMaxBatchSize()

Specified by:

getMaxBatchSize in interface PendingMessageCursor

Returns:

the maximum batch size

setMaxBatchSize

public void setMaxBatchSize(int maxBatchSize)

Description copied from interface: PendingMessageCursor

Set the max batch size

Specified by:

setMaxBatchSize in interface PendingMessageCursor

fillBatch

protected void fillBatch()
                  throws Exception

Throws:

Exception

resetForGC

public void resetForGC()

Description copied from interface: PendingMessageCursor

Give the cursor a hint that we are about to remove messages from memory only

Specified by:

resetForGC in interface PendingMessageCursor

remove

public void remove(org.apache.activemq.broker.region.MessageReference node)

Description copied from interface: PendingMessageCursor

remove a node

Specified by:

remove in interface PendingMessageCursor

gc

public void gc()

Description copied from interface: PendingMessageCursor

free up any internal buffers

Specified by:

gc in interface PendingMessageCursor

setSystemUsage

public void setSystemUsage(SystemUsage usageManager)

Description copied from interface: PendingMessageCursor

Set the UsageManager

Specified by:

setSystemUsage in interface PendingMessageCursor

See Also:

• SystemUsage

hasSpace

public boolean hasSpace()

Specified by:

hasSpace in interface PendingMessageCursor

Returns:

true if the cursor has space to page messages into

isFull

public boolean isFull()

Specified by:

isFull in interface PendingMessageCursor

Returns:

true if the cursor is full

release

public void release()

Description copied from interface: PendingMessageCursor

hint to the cursor to release any locks it might have grabbed after a reset

Specified by:

release in interface PendingMessageCursor

hasMessagesBufferedToDeliver

public boolean hasMessagesBufferedToDeliver()

Specified by:

hasMessagesBufferedToDeliver in interface PendingMessageCursor

Returns:

true if the cursor has buffered messages ready to deliver

getMemoryUsageHighWaterMark

public int getMemoryUsageHighWaterMark()

Specified by:

getMemoryUsageHighWaterMark in interface PendingMessageCursor

Returns:

the memoryUsageHighWaterMark

setMemoryUsageHighWaterMark

public void setMemoryUsageHighWaterMark(int memoryUsageHighWaterMark)

Specified by:

setMemoryUsageHighWaterMark in interface PendingMessageCursor

Parameters:

memoryUsageHighWaterMark - the memoryUsageHighWaterMark to set

getSystemUsage

public SystemUsage getSystemUsage()

Specified by:

getSystemUsage in interface PendingMessageCursor

Returns:

the usageManager

destroy

public void destroy()
             throws Exception

destroy the cursor

Specified by:

destroy in interface PendingMessageCursor

Throws:

Exception

pageInList

public LinkedList<org.apache.activemq.broker.region.MessageReference> pageInList(int maxItems)

Page in a restricted number of messages

Specified by:

pageInList in interface PendingMessageCursor

Parameters:

maxItems - maximum number of messages to return

Returns:

a list of paged in messages

getMaxProducersToAudit

public int getMaxProducersToAudit()

Specified by:

getMaxProducersToAudit in interface PendingMessageCursor

Returns:

the maxProducersToAudit

setMaxProducersToAudit

public void setMaxProducersToAudit(int maxProducersToAudit)

Description copied from interface: PendingMessageCursor

set the maximum number of producers to track at one time

Specified by:

setMaxProducersToAudit in interface PendingMessageCursor

Parameters:

maxProducersToAudit - the maxProducersToAudit to set

getMaxAuditDepth

public int getMaxAuditDepth()

Specified by:

getMaxAuditDepth in interface PendingMessageCursor

Returns:

the maxAuditDepth

setMaxAuditDepth

public void setMaxAuditDepth(int maxAuditDepth)

Description copied from interface: PendingMessageCursor

Set the maximum depth of message ids to track

Specified by:

setMaxAuditDepth in interface PendingMessageCursor

Parameters:

maxAuditDepth - the maxAuditDepth to set

isEnableAudit

public boolean isEnableAudit()

Specified by:

isEnableAudit in interface PendingMessageCursor

Returns:

the enableAudit

setEnableAudit

public void setEnableAudit(boolean enableAudit)

Specified by:

setEnableAudit in interface PendingMessageCursor

Parameters:

enableAudit - the enableAudit to set

isTransient

public boolean isTransient()

Specified by:

isTransient in interface PendingMessageCursor

Returns:

true if the underlying state of this cursor disappears when the broker shuts down

setMessageAudit

public void setMessageAudit(org.apache.activemq.ActiveMQMessageAudit audit)

set the audit

Specified by:

setMessageAudit in interface PendingMessageCursor

Parameters:

audit - new audit component

getMessageAudit

public org.apache.activemq.ActiveMQMessageAudit getMessageAudit()

Specified by:

getMessageAudit in interface PendingMessageCursor

Returns:

the audit

isUseCache

public boolean isUseCache()

Specified by:

isUseCache in interface PendingMessageCursor

Returns:

true if a cache may be used

setUseCache

public void setUseCache(boolean useCache)

Description copied from interface: PendingMessageCursor

use a cache to improve performance

Specified by:

setUseCache in interface PendingMessageCursor

isDuplicate

public boolean isDuplicate(org.apache.activemq.command.MessageId messageId)

recordUniqueId

public boolean recordUniqueId(org.apache.activemq.command.MessageId messageId)

records a message id and checks if it is a duplicate

Parameters:

messageId -

Returns:

true if id is unique, false otherwise.

rollback

public void rollback(org.apache.activemq.command.MessageId id)

Description copied from interface: PendingMessageCursor

remove from auditing the message id

Specified by:

rollback in interface PendingMessageCursor

isStarted

public boolean isStarted()

isPrioritizedMessageSubscriber

public static boolean isPrioritizedMessageSubscriber(Broker broker,
 Subscription sub)

isCacheEnabled

public boolean isCacheEnabled()

Specified by:

isCacheEnabled in interface PendingMessageCursor

Returns:

true if cache is being used

setCacheEnabled

public void setCacheEnabled(boolean val)

rebase

public void rebase()

Specified by:

rebase in interface PendingMessageCursor