Interface EntryLogger

  • All Superinterfaces:
    java.lang.AutoCloseable
    All Known Implementing Classes:
    DefaultEntryLogger, ReadOnlyDefaultEntryLogger

    public interface EntryLogger
    extends java.lang.AutoCloseable
    Entry logger. Sequentially writes entries for a large number of ledgers to a small number of log files, to avoid many random writes. When an entry is added, a location is returned, which consists of the ID of the log into which the entry was added, and the offset of that entry within the log. The location is a long, with 32 bits each for the log ID and the offset. This naturally limits the offset and thus the size of the log to Integer.MAX_VALUE.
    • Method Detail

      • addEntry

        long addEntry​(long ledgerId,
                      io.netty.buffer.ByteBuf buf)
               throws java.io.IOException
        Add an entry for ledger ```ledgerId``` to the entrylog.
        Parameters:
        ledgerId - the ledger for which the entry is being added
        buf - the contents of the entry (this method does not take ownership of the refcount)
        Returns:
        the location in the entry log of the added entry
        Throws:
        java.io.IOException
      • readEntry

        io.netty.buffer.ByteBuf readEntry​(long entryLocation)
                                   throws java.io.IOException,
                                          Bookie.NoEntryException
        Read an entry from an entrylog location.
        Parameters:
        entryLocation - the location from which to read the entry
        Returns:
        the entry
        Throws:
        java.io.IOException
        Bookie.NoEntryException
      • readEntry

        io.netty.buffer.ByteBuf readEntry​(long ledgerId,
                                          long entryId,
                                          long entryLocation)
                                   throws java.io.IOException,
                                          Bookie.NoEntryException
        Read an entry from an entrylog location, and verify that is matches the expected ledger and entry ID.
        Parameters:
        ledgerId - the ledgerID to match
        entryId - the entryID to match
        entryLocation - the location from which to read the entry
        Returns:
        the entry
        Throws:
        java.io.IOException
        Bookie.NoEntryException
      • flush

        void flush()
            throws java.io.IOException
        Flush any outstanding writes to disk.
        Throws:
        java.io.IOException
      • close

        void close()
            throws java.io.IOException
        Specified by:
        close in interface java.lang.AutoCloseable
        Throws:
        java.io.IOException
      • newCompactionLog

        CompactionEntryLog newCompactionLog​(long logToCompact)
                                     throws java.io.IOException
        Create a new entrylog into which compacted entries can be added. There is a 1-1 mapping between logs that are being compacted and the log the compacted entries are written to.
        Throws:
        java.io.IOException
      • incompleteCompactionLogs

        java.util.Collection<CompactionEntryLog> incompleteCompactionLogs()
        Return a collection of all the compaction entry logs which have been compacted, but have not been cleaned up.
      • getFlushedLogIds

        java.util.Collection<java.lang.Long> getFlushedLogIds()
        Get the log ids for the set of logs which have been completely flushed to disk. Only log ids in this set are considered for either compaction or garbage collection.
      • scanEntryLog

        void scanEntryLog​(long entryLogId,
                          EntryLogScanner scanner)
                   throws java.io.IOException
        Scan the given entrylog, returning all entries contained therein.
        Throws:
        java.io.IOException
      • getEntryLogMetadata

        default EntryLogMetadata getEntryLogMetadata​(long entryLogId)
                                              throws java.io.IOException
        Retrieve metadata for the given entrylog ID. The metadata contains the size of the log, the size of the data in the log which is still active, and a list of all the ledgers contained in the log and the size of the data stored for each ledger.
        Throws:
        java.io.IOException
      • getEntryLogMetadata

        EntryLogMetadata getEntryLogMetadata​(long entryLogId,
                                             AbstractLogCompactor.Throttler throttler)
                                      throws java.io.IOException
        Retrieve metadata for the given entrylog ID. The metadata contains the size of the log, the size of the data in the log which is still active, and a list of all the ledgers contained in the log and the size of the data stored for each ledger.
        Throws:
        java.io.IOException
      • logExists

        boolean logExists​(long logId)
        Check whether an entrylog with the given ID exists.
      • removeEntryLog

        boolean removeEntryLog​(long entryLogId)
        Delete the entrylog with the given ID.
        Returns:
        false if the entrylog doesn't exist.