Package com.atlassian.confluence.impl.journal

Class DefaultJournalService

java.lang.Object

com.atlassian.confluence.impl.journal.DefaultJournalService

All Implemented Interfaces:

JournalService

Direct Known Subclasses:

DefaultIndexJournalService

public class DefaultJournalService
extends Object
implements JournalService

This is the default implementation of JournalService.

Since:

5.6

Constructor Summary

Constructors

Constructor	Description
DefaultJournalService(JournalManager journalManager)

Method Summary

Modifier and Type	Method	Description
int	countEntries(@NonNull JournalIdentifier journalId)	Counts the number of entries in a journal.
long	enqueue(@NonNull JournalEntry entry)	Adds the given entry to a journal.
Iterable<JournalEntry>	peek(@NonNull JournalIdentifier journalId, int maxEntries)	Return a copy of journal entries that are waiting to be processed.
<V> V	processNewEntries(@NonNull JournalIdentifier journalId, int maxEntries, @NonNull Function<Iterable<JournalEntry>,EntryProcessorResult<V>> entryProcessor)	Processes journal entries that were added since the last time this method was called for this journal on this cluster node.
void	reset(@NonNull JournalIdentifier journalId)	Resets the state of the journal so that all entries currently in the journal will be skipped.
void	waitForRecentEntriesToBecomeVisible()	Waits long enough to ensure that entries added before calling this method will be available to subsequent call to JournalService.processNewEntries(JournalIdentifier, int, Function).

Methods inherited from class java.lang.Object

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

Constructor Details

DefaultJournalService

public DefaultJournalService(JournalManager journalManager)

Method Details

enqueue

public long enqueue(@NonNull JournalEntry entry)
             throws ServiceException

Description copied from interface: JournalService

Adds the given entry to a journal.

New journal is automatically created if a journal with the given name does not exists.

Specified by:

enqueue in interface JournalService

Parameters:

entry - entry to persist

Returns:

id generated for the entry

Throws:

ServiceException - if the entry could not be persisted

processNewEntries

public <V> V processNewEntries(@NonNull JournalIdentifier journalId,
 int maxEntries,
 @NonNull Function<Iterable<JournalEntry>,EntryProcessorResult<V>> entryProcessor)
                        throws ServiceException

Description copied from interface: JournalService

Processes journal entries that were added since the last time this method was called for this journal on this cluster node.

This method does not return entries that were added immediately before calling this method. Use JournalService.waitForRecentEntriesToBecomeVisible() for ensuring these entries will be included.

This method can miss some entries due to identifier assignment and entry insertion not being an atomic operation. The risk of missed entries can be reduced by creating new entries as close to transaction commit as possible.

If entryProcessor throws an exception, the same entries will be returned again when this method is next called for this journal on this cluster node.

New journal is automatically created if a journal with the given name does not exists.

Specified by:

processNewEntries in interface JournalService

Parameters:

journalId - only entries with this journal id will be returned

maxEntries - maximum number of entries to process

entryProcessor - function that will process entries that were added since the last time

Returns:

result of entryProcessor

Throws:

ServiceException - if entries could not be fetched or the journal state could not be saved

waitForRecentEntriesToBecomeVisible

public void waitForRecentEntriesToBecomeVisible()
                                         throws InterruptedException

Description copied from interface: JournalService

Waits long enough to ensure that entries added before calling this method will be available to subsequent call to JournalService.processNewEntries(JournalIdentifier, int, Function).

Specified by:

waitForRecentEntriesToBecomeVisible in interface JournalService

Throws:

InterruptedException - if the thread got interrupted

peek

public Iterable<JournalEntry> peek(@NonNull JournalIdentifier journalId,
 int maxEntries)
                            throws ServiceException

Description copied from interface: JournalService

Return a copy of journal entries that are waiting to be processed.

Specified by:

peek in interface JournalService

Parameters:

journalId - only entries with this journal id will be returned

maxEntries - maximum number of entries to return

Returns:

a copy of journal entries that are waiting to be processed

Throws:

ServiceException - if entries could not be fetched

reset

public void reset(@NonNull JournalIdentifier journalId)
           throws ServiceException

Description copied from interface: JournalService

Resets the state of the journal so that all entries currently in the journal will be skipped.

Specified by:

reset in interface JournalService

Parameters:

journalId - identifier of the journal to reset

Throws:

ServiceException - if the reset fails

countEntries

public int countEntries(@NonNull JournalIdentifier journalId)
                 throws ServiceException

Description copied from interface: JournalService

Counts the number of entries in a journal.

Specified by:

countEntries in interface JournalService

Parameters:

journalId - identifier of the journal

Throws:

ServiceException - if entries could not be counted