Class ReclaimSpace

java.lang.Object
org.apache.derby.impl.store.raw.data.ReclaimSpace
All Implemented Interfaces:
Serviceable
public final class ReclaimSpace extends Object implements Serviceable
Post commit work to reclaim some space from the raw store. This is a wrapper class for the real serviceable class who wraps this on top of itself so different things can be identified.

  • Field Details

    • serviceASAP

      private boolean serviceASAP

    • containerId

      private ContainerKey containerId

    • pageId

      private PageKey pageId

    • headRowHandle

      private RecordHandle headRowHandle

    • columnId

      private int columnId

    • columnPageId

      private long columnPageId

    • columnRecordId

      private int columnRecordId

    • timeStamp

      private PageTimeStamp timeStamp

    • attempts

      private int attempts

    • processor

      private DataFactory processor

    • reclaim

      private int reclaim

    • CONTAINER

      public static final int CONTAINER
      See Also:

    • PAGE

      public static final int PAGE
      See Also:

    • ROW_RESERVE

      public static final int ROW_RESERVE
      See Also:

    • COLUMN_CHAIN

      public static final int COLUMN_CHAIN
      See Also:

  • Constructor Details

    • ReclaimSpace

      public ReclaimSpace(int reclaim, ContainerKey containerId, DataFactory processor, boolean serviceASAP)

    • ReclaimSpace

      public ReclaimSpace(int reclaim, PageKey pageId, DataFactory processor, boolean serviceASAP)

    • ReclaimSpace

      public ReclaimSpace(int reclaim, RecordHandle headRowHandle, DataFactory processor, boolean serviceASAP)

    • ReclaimSpace

      public ReclaimSpace(int reclaim, RecordHandle headRowHandle, int columnId, long ovPageId, int ovRecordId, PageTimeStamp timeStamp, DataFactory processor, boolean serviceASAP)

  • Method Details

    • initContainerInfo

      private void initContainerInfo(ContainerKey containerId, int reclaim, DataFactory processor, boolean serviceASAP)

    • serviceASAP

      public boolean serviceASAP()
      Description copied from interface: Serviceable
      If this work should be done as soon as possible, then return true. If it doesn't make any difference if it is done sooner rather than later, then return false. The difference is whether or not the daemon service will be notified to work on this when this work is enqueued or subscribed, in case the serviceable work is put together but not sent to the daemon service directly, like in post commit processing

      MT - MT safe

      Specified by:
      serviceASAP in interface Serviceable

    • performWork

      public int performWork(ContextManager context) throws StandardException
      Description copied from interface: Serviceable
      Do whatever it is that you want the daemon to do for you. There may be multiple daemon objects on different thread calling performWork at the same time. The DaemonService will always call performWork with a context manager set up. the DaemonService will clean up the context if an exception is thrown. However, it is up to performWork to manage its own transaction. If you start a transaction in performWork, you must commit or abort it at the end. You may leave the transaction open so that other serviceable may use the transaction and context without starting a new one. On the same token, there may already be an opened transaction on the context. Serviceable performWork should always check the state of the context before use. A Serviceable object should be well behaved while it is performing the daemon work, i.e., it should not take too many resources or hog the CPU for too long or deadlock with anyone else.
      Specified by:
      performWork in interface Serviceable
      Parameters:
      context - the contextManager set up by the DaemonService. There may or may not be the necessary context on it, depending on which other Serviceable object it has done work for.
      Returns:
      the return status is only significant if the Serviceable client was enqueued instead of subscribed. For subscribed client, the return status is ignored. For enqueue client, it returns DONE or REQUEUE. If a REQUEUEd is returned, it would be desirable if this should not be serviceASAP, although no harm is done if this still maintains that this should be serviced ASAP ...
      Throws:
      StandardException - Standard Derby exception policy

      MT - depends on the work. Be wary of multiple DaemonService thread calling at the same time if you subscribe or enqueue multiple times.

    • serviceImmediately

      public boolean serviceImmediately()
      Description copied from interface: Serviceable
      If this work should be done immediately on the user thread then return true. If it doesn't make any difference if this work is done on a the user thread immediately or if it is performed by another thread asynchronously later, then return false.
      Specified by:
      serviceImmediately in interface Serviceable

    • getContainerId

      public final ContainerKey getContainerId()

    • getPageId

      public final PageKey getPageId()

    • getHeadRowHandle

      public final RecordHandle getHeadRowHandle()

    • getColumnId

      public final int getColumnId()

    • getColumnPageId

      public final long getColumnPageId()

    • getColumnRecordId

      public final int getColumnRecordId()

    • getPageTimeStamp

      public final PageTimeStamp getPageTimeStamp()

    • reclaimWhat

      public final int reclaimWhat()

    • incrAttempts

      public final int incrAttempts()

    • toString

      public String toString()
      Overrides:
      toString in class Object