Package com.streambase.liveview.client

Class LiveResult

java.lang.Object
com.streambase.liveview.client.LiveResult
All Implemented Interfaces:
QueryListener, EventListener
public class LiveResult extends Object implements QueryListener
A live result is a QueryListener the receives and maintains a local copy of tuples. Methods exists to retrieve the current list of tuples maintained locally. The live results can also be constructed with a nested QueryListener. In this mode the live result will propagate events it received to the nested listener. It will also modify update and remove events to include the old or removed tuple (in addition to the new tuple.)

  • Constructor Details

    • LiveResult

      public LiveResult(QueryListener listener)
      Contruct a LiveResult that will maintain the tuples for you, plus you can also be informed of all the events. All events will be passed on to your listener. However, the update events will be populated with a complete old and new tuples. (Without the LiveResult, then update events only have the
      Parameters:
      listener - The listener to dispatch events to when changes occur on this LiveResult

    • LiveResult

      public LiveResult()
      Construct a LiveResult that will maintain the list of tuples for you which you can query at your leisure.

  • Method Details

    • setTimeout

      public void setTimeout(int ms)
      setTimeout limits the amount of time to wait for the snapshot to complete.
      Parameters:
      ms - - number of milliseconds to wait before abandoning waiting for snapshot complete.
      Since:
      1.4.1

    • isEmpty

      public final boolean isEmpty()
      Is the result empty
      Returns:
      true is the result is empty

    • size

      public final int size()
      The size of the result
      Returns:
      the size

    • getTuple

      public Tuple getTuple(KeyValue keyValue)
      Get a tuple from the KeyValue obtained from an Event. Note that this will return null if the tuple is not in the list of tuples, that is, before it has been added or after it has been removed.
      Parameters:
      keyValue - of type KeyValue.
      Returns:
      Tuple.

    • getTuples

      public final Collection<Tuple> getTuples()
      Retrieves the current tuples in the result.
      Returns:
      the collection of tuples in the result.

    • getTuples

      public final Collection<Tuple> getTuples(boolean waitForSnapshot)
      Retrieves the current tuples in the result
      Parameters:
      waitForSnapshot - waits for the query snapshot to complete before returning from the call
      Returns:
      the collection of tuples in the result

    • waitForSnapshot

      public final void waitForSnapshot()
      Blocking call that waits for the query snapshot to complete.

    • tupleAdded

      public void tupleAdded(TupleAddedEvent event)
      Event when a new tuple is added to the result.
      Specified by:
      tupleAdded in interface QueryListener
      Parameters:
      event - add event
      Throws:
      TupleException

    • getKeyFromEvent

      protected Long getKeyFromEvent(AbstractTupleEvent event)

    • getKeyForEvent

      protected Long getKeyForEvent(AbstractTupleEvent event, boolean remove)

    • tupleUpdated

      public void tupleUpdated(TupleUpdatedEvent event)
      Event when an existing tuple in the result is updated.
      Specified by:
      tupleUpdated in interface QueryListener
      Parameters:
      event - update event

    • tupleRemoved

      public void tupleRemoved(TupleRemovedEvent event)
      Event when an existing tuple is removed from the result.
      Specified by:
      tupleRemoved in interface QueryListener
      Parameters:
      event - remove event

    • snapshotBegin

      public void snapshotBegin(BeginSnapshotEvent event)
      Event to indicate the start of the result snapshot. This is the first method called when a query starts returning results, but this method is also called to indicate a reset (a complete restart of the query.)
      Specified by:
      snapshotBegin in interface QueryListener
      Parameters:
      event - snapshot begin

    • snapshotEnd

      public void snapshotEnd(EndSnapshotEvent event)
      Event to indicate the query snapshot is complete.
      Specified by:
      snapshotEnd in interface QueryListener
      Parameters:
      event - snapshot end

    • exceptionRaised

      public void exceptionRaised(QueryExceptionEvent event)
      Event when an exception occurs during the query. Since 1.3, reaching the row limit is considered an exception.
      Specified by:
      exceptionRaised in interface QueryListener
      Parameters:
      event - exception event

    • queryClosed

      public void queryClosed(QueryClosedEvent event)
      Event when a query being listened to is closed.
      Specified by:
      queryClosed in interface QueryListener
      Parameters:
      event - query closed event

    • deleteBegin

      public void deleteBegin(BeginDeleteEvent event)
      Description copied from interface: QueryListener
      Event to indicate the start of delete query.
      Specified by:
      deleteBegin in interface QueryListener
      Parameters:
      event - delete begin

    • deleteEnd

      public void deleteEnd(EndDeleteEvent event)
      Description copied from interface: QueryListener
      Event to indicate the delete query is complete.
      Specified by:
      deleteEnd in interface QueryListener
      Parameters:
      event - delete end

    • aggMarkEnd

      public void aggMarkEnd(EndAggMarkEvent event)
      Description copied from interface: QueryListener
      Event to indicate that the set of aggregation results since the last aggMarkBegin event are now consistent and will not change until the next aggMarkBegin.
      Specified by:
      aggMarkEnd in interface QueryListener
      Parameters:
      event - the EndAggMarkEvent

    • aggMarkBegin

      public void aggMarkBegin(BeginAggMarkEvent event)
      Description copied from interface: QueryListener
      Event to indicate that the set of aggregation results may be changing so some results may be from an older generation while other may be from a newer one.
      Specified by:
      aggMarkBegin in interface QueryListener
      Parameters:
      event - the BeginAggMarkEvent

    • isSnapshotComplete

      public boolean isSnapshotComplete()
      Retreives whether or not the LiveResult is up to date.
      Returns:
      true if the LiveResult is up to date.