Package com.atlassian.confluence.api.service.journal

Interface JournalService

All Known Subinterfaces:
IndexJournalService
All Known Implementing Classes:
DefaultIndexJournalService, DefaultJournalService
@PublicApi public interface JournalService
This service is an entry point to the journal subsystem.

Typical way to use journal subsystem is to call enqueue(com.atlassian.confluence.api.model.journal.JournalEntry) to queue new entries that should be actioned on each cluster node. Later on queued entries can be processed by calling processNewEntries(JournalIdentifier, int, Function) on each cluster node. Subsequent calls to processEntries will be passed only entries that were added since the last call on that cluster node.

Since:
5.6

  • Method Details

    • enqueue

      long enqueue(@NonNull JournalEntry entry) throws ServiceException
      Adds the given entry to a journal.

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

      Parameters:
      entry - entry to persist
      Returns:
      id generated for the entry
      Throws:
      ServiceException - if the entry could not be persisted

    • processNewEntries

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

      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
      Since:
      7.0.1

    • waitForRecentEntriesToBecomeVisible

      void waitForRecentEntriesToBecomeVisible() throws InterruptedException
      Waits long enough to ensure that entries added before calling this method will be available to subsequent call to processNewEntries(JournalIdentifier, int, Function).
      Throws:
      InterruptedException - if the thread got interrupted

    • peek

      Iterable<JournalEntry> peek(@NonNull JournalIdentifier journalId, int maxEntries) throws ServiceException
      Return a copy of journal entries that are waiting to be processed.
      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

      void reset(@NonNull JournalIdentifier journalId) throws ServiceException
      Resets the state of the journal so that all entries currently in the journal will be skipped.
      Parameters:
      journalId - identifier of the journal to reset
      Throws:
      ServiceException - if the reset fails

    • countEntries

      int countEntries(@NonNull JournalIdentifier journalId) throws ServiceException
      Counts the number of entries in a journal.
      Parameters:
      journalId - identifier of the journal
      Throws:
      ServiceException - if entries could not be counted