Package com.espertech.esper.common.internal.view.expression

Class ExpressionBatchView

java.lang.Object
com.espertech.esper.common.internal.view.core.ViewSupport
com.espertech.esper.common.internal.view.expression.ExpressionViewBase
com.espertech.esper.common.internal.view.expression.ExpressionBatchView
All Implemented Interfaces:
AgentInstanceMgmtCallback, VariableChangeCallback, DataWindowView, View, Viewable, ViewDataVisitable, Iterable<EventBean>
public class ExpressionBatchView extends ExpressionViewBase
This view is a moving window extending the into the past until the expression passed to it returns false.

  • Field Details

    • window

      protected final Set<EventBean> window

    • lastBatch

      protected EventBean[] lastBatch

    • newestEventTimestamp

      protected long newestEventTimestamp

    • oldestEventTimestamp

      protected long oldestEventTimestamp

    • oldestEvent

      protected EventBean oldestEvent

    • newestEvent

      protected EventBean newestEvent

  • Constructor Details

  • Method Details

    • isEmpty

      public boolean isEmpty()
      Returns true if the window is empty, or false if not empty.
      Returns:
      true if empty

    • scheduleCallback

      public void scheduleCallback()
      Description copied from class: ExpressionViewBase
      Implemented to check the expiry expression.
      Specified by:
      scheduleCallback in class ExpressionViewBase

    • update

      public void update(EventBean[] newData, EventBean[] oldData)
      Description copied from interface: View
      Notify that data has been added or removed from the Viewable parent. The last object in the newData array of objects would be the newest object added to the parent view. The first object of the oldData array of objects would be the oldest object removed from the parent view.

      If the call to update contains new (inserted) data, then the first argument will be a non-empty list and the second will be empty. Similarly, if the call is a notification of deleted data, then the first argument will be empty and the second will be non-empty. Either the newData or oldData will be non-null. This method won't be called with both arguments being null, but either one could be null. The same is true for zero-length arrays. Either newData or oldData will be non-empty. If both are non-empty, then the update is a modification notification.

      When update() is called on a view by the parent object, the data in newData will be in the collection of the parent, and its data structures will be arranged to reflect that. The data in oldData will not be in the parent's data structures, and any access to the parent will indicate that that data is no longer there.

      Parameters:
      newData - is the new data that has been added to the parent view
      oldData - is the old data that has been removed from the parent view

    • expire

      public void expire(int numEventsInBatch)

    • visitView

      public void visitView(ViewDataVisitor viewDataVisitor)

    • iterator

      public final Iterator<EventBean> iterator()
      Description copied from interface: Viewable
      Allows iteration through all elements in this viewable. The iterator will return the elements in the collection in their natural order, or, if there is no natural ordering, in some unpredictable order.
      Returns:
      an iterator which will go through all current elements in the collection.

    • update

      public void update(Object newValue, Object oldValue)
      Description copied from interface: VariableChangeCallback
      Indicate a change in variable value.
      Specified by:
      update in interface VariableChangeCallback
      Overrides:
      update in class ExpressionViewBase
      Parameters:
      newValue - new value
      oldValue - old value