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

Class WeightedAverageView

java.lang.Object
com.espertech.esper.common.internal.view.core.ViewSupport
com.espertech.esper.common.internal.view.derived.WeightedAverageView
All Implemented Interfaces:
DerivedValueView, View, Viewable, Iterable<EventBean>
public class WeightedAverageView extends ViewSupport implements DerivedValueView
View for computing a weighted average. The view uses 2 fields within the parent view to compute the weighted average. The X field and weight field. In a price-volume example it calculates the volume-weighted average price as (sum(price * volume) / sum(volume)). Example: weighted_avg("price", "volume")

  • Field Details

    • sumXtimesW

      protected double sumXtimesW

    • sumW

      protected double sumW

    • currentValue

      protected double currentValue

    • lastValuesEventNew

      protected Object[] lastValuesEventNew

  • Constructor Details

  • Method Details

    • 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.

      Specified by:
      update in interface View
      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

    • getEventType

      public final EventType getEventType()
      Description copied from interface: Viewable
      Provides metadata information about the type of object the event collection contains.
      Specified by:
      getEventType in interface Viewable
      Returns:
      metadata for the objects in the collection

    • 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.
      Specified by:
      iterator in interface Iterable<EventBean>
      Specified by:
      iterator in interface Viewable
      Returns:
      an iterator which will go through all current elements in the collection.

    • createEventType

      public static EventType createEventType(StatViewAdditionalPropsForge additionalProps, ViewForgeEnv env)

    • getSumXtimesW

      public double getSumXtimesW()

    • setSumXtimesW

      public void setSumXtimesW(double sumXtimesW)

    • getSumW

      public double getSumW()

    • setSumW

      public void setSumW(double sumW)

    • getCurrentValue

      public double getCurrentValue()

    • setCurrentValue

      public void setCurrentValue(double currentValue)

    • getLastValuesEventNew

      public Object[] getLastValuesEventNew()

    • setLastValuesEventNew

      public void setLastValuesEventNew(Object[] lastValuesEventNew)

    • getViewFactory

      public ViewFactory getViewFactory()