Package com.tangosol.io.journal

Class AbstractJournalRM.JournalFile

java.lang.Object
com.tangosol.io.journal.AbstractJournalRM.JournalFile
All Implemented Interfaces:
Disposable, AutoCloseable
Direct Known Subclasses:
AbstractJournalRM.CollectorDaemon.InvokeGCJournalFile, FlashJournalRM.JournalFile, RamJournalRM.JournalFile
Enclosing class:
AbstractJournalRM
protected abstract class AbstractJournalRM.JournalFile extends Object implements Disposable
A JournalFile object is created for each file used to store the journal contents. It is created in an initial "append" mode -- which may be interrupted from time to time by a "congested" mode if writes are falling too far behind, it then transitions to a "full" mode, and once enough of its storage has been released it transitions to an "evacuating" mode, which (once evacuated) becomes "garbage" and (upon deletion) is "discarded".

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected final Condition
    f_journalFileCondition
    A condition associated with a synchronization lock above that is used to wait for notification and to notify waiting threads.
    protected final Lock
    f_journalFileLock
    The lock that should be used to control concurrent access to this Journal File.
    protected final AtomicLong
    m_cbReleased
    Amount of data that has been released.
    protected final AtomicLong
    m_cbWritten
    Amount of data that has been written.
    protected boolean
    m_fNotifiedFull
    Set to true when the JournalFile is notified that it is full and its contents have been fully written.
    protected AbstractJournalRM.JournalFile
    m_jrnlfileNext
    The JournalFile that "comes after" this JournalFile in the journal.
    protected final AtomicLong
    m_lStateOffset
    Current state of the JournalFile and the appending offset within the file.
    protected final int
    m_nFile
    The file index.
    static final long
    STATE_APPENDING
    State: File is being appended to.
    static final long
    STATE_CONGESTION
    State: File is appending, but there is congestion forcing a wait by all appending threads.
    static final long
    STATE_DISCARDED
    State: File has been discarded.
    static final long
    STATE_EVACUATING
    State: Remaining entries in the file are being evacuated.
    static final long
    STATE_FULL
    State: File is full and appends are no longer occurring.
    static final long
    STATE_GARBAGE
    State: File is garbage and can safely be discarded.
    static final long
    STATE_MASK
    The bits of the m_lStateOffset that are used for the current state of the file (one of the STATE_* constants).
    static final long
    STATE_RESERVED
    State: File is reserved by the CollectorDaemon.

  • Constructor Summary

    Constructors
    Constructor
    Description
    JournalFile(int nFile)
    Construct a Journal File.

  • Method Summary

    Modifier and Type
    Method
    Description
    protected boolean
    compareAndSetOffset(long lPrevValue, long lOffset)
    Specify the new offset value of this JournalFile.
    protected boolean
    compareAndSetState(long lPrevValue, long lState)
    Specify the current state of this JournalFile unless the state is STATE_RESERVED as it is a special case and should be set via setReserved(boolean).
    abstract void
    dispose()
    Invoked when all resources owned by the implementer can safely be released.
    abstract long
    enqueue(Binary bin)
    Enqueue a Binary value to be written to this file, returning a ticket, or return 0L if this file is full and the append has to occur to a new file.
    void
    evacuate()
    Called by the CollectorDaemon to evacuate all remaining data from the JournalFile.
    long
    getBytesWritten()
    Determine the number of bytes written.
    protected String
    getDescription()
    Format the object attributes into a String for inclusion in the String returned from the toString() method.
    int
    getFileId()
    Determine the file id (0-511) for this JournalFile.
    AbstractJournalRM.JournalFile
    getNextJournalFile()
    Determine the JournalFile for the file in the journal that follows the file represented by this JournalFile.
    long
    getOffset()
    Determine the current append offset (or length) of this JournalFile.
    protected long
    getOffset(long lStateOffset)
    Determine the current append offset (or length) from the provided long.
    long
    getReleased()
    Determine the number of bytes that have been released from this JournalFile.
    long
    getState()
    Determine the current state of this JournalFile.
    protected long
    getState(long lState)
    Determine the state of the provided (potentially) unmasked lState.
    boolean
    isAppending()
    Return whether the JournalFile can be appended to.
    boolean
    isReserved()
    Return whether the JournalFile has been reserved thus can not be used by clients.
    void
    notifyWriteCompleted()
    Called by the CollectorDaemon the first time that the JournalFile is encountered in its FULL state and its data has all been written.
    abstract Binary
    read(long lTicket)
    Read the Binary associated with the specified ticket from the journal file.
    void
    release(int cbValue)
    Release the specified number of bytes from this journal file.
    void
    setNextJournalFile(AbstractJournalRM.JournalFile jrnlfileNext)
    Once this file has been filled, it gets a reference to the file that follows it.
    protected void
    setReserved(boolean fReserved)
    Specify whether the current JournalFile is reserved.
    protected void
    setState(long lState)
    Specify the current state of this JournalFile.
    String
    toString()
    void
    touch()
    This method is called periodically by the collector daemon to indicate that the file is still being used.

    Methods inherited from class java.lang.Object

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

    Methods inherited from interface com.oracle.coherence.common.base.Disposable

    close

  • Field Details

    • STATE_APPENDING

      public static final long STATE_APPENDING
      State: File is being appended to.
      See Also:

    • STATE_CONGESTION

      public static final long STATE_CONGESTION
      State: File is appending, but there is congestion forcing a wait by all appending threads.
      See Also:

    • STATE_FULL

      public static final long STATE_FULL
      State: File is full and appends are no longer occurring.
      See Also:

    • STATE_EVACUATING

      public static final long STATE_EVACUATING
      State: Remaining entries in the file are being evacuated.
      See Also:

    • STATE_GARBAGE

      public static final long STATE_GARBAGE
      State: File is garbage and can safely be discarded.
      See Also:

    • STATE_DISCARDED

      public static final long STATE_DISCARDED
      State: File has been discarded.
      See Also:

    • STATE_RESERVED

      public static final long STATE_RESERVED
      State: File is reserved by the CollectorDaemon. This state differs from the others as it may exist in combination with the other states thus is a marker.
      See Also:

    • STATE_MASK

      public static final long STATE_MASK
      The bits of the m_lStateOffset that are used for the current state of the file (one of the STATE_* constants).
      See Also:

    • m_nFile

      protected final int m_nFile
      The file index. Immutable field.

    • m_lStateOffset

      protected final AtomicLong m_lStateOffset
      Current state of the JournalFile and the appending offset within the file. These two values are maintained in a single "long" value so that the file can be appended to and transitioned from state to state in an atomic manner, i.e. when the file gets close to being full, it can be transitioned from the "appending" state in the same manner as an append itself is done (which simply updates the offset).

    • m_cbWritten

      protected final AtomicLong m_cbWritten
      Amount of data that has been written.

    • m_cbReleased

      protected final AtomicLong m_cbReleased
      Amount of data that has been released.

    • m_jrnlfileNext

      protected volatile AbstractJournalRM.JournalFile m_jrnlfileNext
      The JournalFile that "comes after" this JournalFile in the journal.

    • m_fNotifiedFull

      protected boolean m_fNotifiedFull
      Set to true when the JournalFile is notified that it is full and its contents have been fully written.

    • f_journalFileLock

      protected final Lock f_journalFileLock
      The lock that should be used to control concurrent access to this Journal File.

    • f_journalFileCondition

      protected final Condition f_journalFileCondition
      A condition associated with a synchronization lock above that is used to wait for notification and to notify waiting threads.

  • Constructor Details

    • JournalFile

      public JournalFile(int nFile)
      Construct a Journal File.
      Parameters:
      nFile - the file number in the range 0-511 (inclusive)

  • Method Details

    • enqueue

      public abstract long enqueue(Binary bin)
      Enqueue a Binary value to be written to this file, returning a ticket, or return 0L if this file is full and the append has to occur to a new file.
      Parameters:
      bin - the value to append to the journal file
      Returns:
      a ticket if the Binary has successfully been enqueued, or 0L if the file is full

    • read

      public abstract Binary read(long lTicket)
      Read the Binary associated with the specified ticket from the journal file.
      Parameters:
      lTicket - a ticket previously returned from enqueue(com.tangosol.util.Binary)
      Returns:
      the Binary value that is associated with the ticket

    • release

      public void release(int cbValue)
      Release the specified number of bytes from this journal file.
      Parameters:
      cbValue - the number of bytes that are being released

    • getFileId

      public int getFileId()
      Determine the file id (0-511) for this JournalFile.
      Returns:
      the file id for this JournalFile

    • getState

      public long getState()
      Determine the current state of this JournalFile.
      Returns:
      the one of the STATE_* constants

    • getOffset

      public long getOffset()
      Determine the current append offset (or length) of this JournalFile.
      Returns:
      the current append offset

    • getBytesWritten

      public long getBytesWritten()
      Determine the number of bytes written.
      Returns:
      the number of bytes that have been reported to have been written

    • getReleased

      public long getReleased()
      Determine the number of bytes that have been released from this JournalFile.
      Returns:
      the number of bytes that have been released from this file

    • isAppending

      public boolean isAppending()
      Return whether the JournalFile can be appended to.
      Returns:
      whether the JournalFile can be appended to

    • isReserved

      public boolean isReserved()
      Return whether the JournalFile has been reserved thus can not be used by clients.
      Returns:
      whether the JournalFile has been reserved

    • touch

      public void touch()
      This method is called periodically by the collector daemon to indicate that the file is still being used.

    • getNextJournalFile

      public AbstractJournalRM.JournalFile getNextJournalFile()
      Determine the JournalFile for the file in the journal that follows the file represented by this JournalFile.
      Returns:
      the next file in the journal, or null if it has not yet been set

    • setNextJournalFile

      public void setNextJournalFile(AbstractJournalRM.JournalFile jrnlfileNext)
      Once this file has been filled, it gets a reference to the file that follows it.
      Parameters:
      jrnlfileNext - the next file in the journal

    • getDescription

      protected String getDescription()
      Format the object attributes into a String for inclusion in the String returned from the toString() method.
      Returns:
      a comma-delimited String listing the attributes of this object in the form "attribute=value"

    • notifyWriteCompleted

      public void notifyWriteCompleted()
      Called by the CollectorDaemon the first time that the JournalFile is encountered in its FULL state and its data has all been written.

    • evacuate

      public void evacuate()
      Called by the CollectorDaemon to evacuate all remaining data from the JournalFile.

    • setReserved

      protected void setReserved(boolean fReserved)
      Specify whether the current JournalFile is reserved.
      Parameters:
      fReserved - whether the JournalFile is reserved

    • dispose

      public abstract void dispose()
      Invoked when all resources owned by the implementer can safely be released.

      Once disposed of the object should no longer be considered to be usable.

      Note the Disposable interface is compatible with try-with-resources which will automatically invoke this method.

      Specified by:
      dispose in interface Disposable

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • getState

      protected long getState(long lState)
      Determine the state of the provided (potentially) unmasked lState.
      Parameters:
      lState - the journal file state
      Returns:
      the state only value

    • setState

      protected void setState(long lState)
      Specify the current state of this JournalFile.
      Parameters:
      lState - one of the STATE_* constants

    • compareAndSetState

      protected boolean compareAndSetState(long lPrevValue, long lState)
      Specify the current state of this JournalFile unless the state is STATE_RESERVED as it is a special case and should be set via setReserved(boolean).
      Parameters:
      lPrevValue - the expected state value
      lState - one of the STATE_* constants, except STATE_RESERVED
      Returns:
      true if the value was successfully cas'd

    • compareAndSetOffset

      protected boolean compareAndSetOffset(long lPrevValue, long lOffset)
      Specify the new offset value of this JournalFile.
      Parameters:
      lPrevValue - the expected state value
      lOffset - the new offset value
      Returns:
      true if the value was successfully cas'd

    • getOffset

      protected long getOffset(long lStateOffset)
      Determine the current append offset (or length) from the provided long.
      Parameters:
      lStateOffset - the long value holding both the state and offset
      Returns:
      the current append offset