Class NodeStats


  • public abstract class NodeStats
    extends java.lang.Object
    This is a utility class to represent rowCount, rate and window.
    • Field Detail

      • UNKNOWN

        public static final NodeStats UNKNOWN
        Returns an instance with all values set to INFINITY. This will be only used when the node is not a BeamRelNode and we don't have an estimation implementation for it in the metadata handler. In this case we return INFINITE and it will be propagated up in the estimates.
    • Constructor Detail

      • NodeStats

        public NodeStats()
    • Method Detail

      • getRowCount

        public abstract double getRowCount()
      • getRate

        public abstract double getRate()
      • getWindow

        public abstract double getWindow()
        This method returns the number of tuples in each window. It is different than the windowing notion of Beam.
      • create

        public static NodeStats create​(double rowCount,
                                       double rate,
                                       double window)
      • create

        public static NodeStats create​(double rowCount)
        It creates an instance with rate=0 and window=rowCount for bounded sources.
      • isUnknown

        public boolean isUnknown()
        If any of the values for rowCount, rate or window is infinite, it returns true.
      • multiply

        public NodeStats multiply​(double factor)