Class Variable

java.lang.Object
org.rrd4j.data.Variable
Direct Known Subclasses:
Variable.AVERAGE, Variable.FIRST, Variable.LAST, Variable.LSLCORREL, Variable.LSLINT, Variable.LSLSLOPE, Variable.MAX, Variable.MIN, Variable.PERCENTILE, Variable.STDDEV, Variable.TOTAL

public abstract class Variable extends Object
An abstract class to help extract single value from a set of value (VDEF in rrdtool) It can be used to add new fancy statistical calculation with rrd values
  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static class 
    Calculate the average of the data points.
    (package private) static final class 
    The sort used by rrdtool for percent, where NaN < -INF < finite values < INF
    static class 
    Find the first valid data point and it's timestamp
    static class 
    Find the first last valid point and it's timestamp
    static class 
    Calculate the correlation coefficient of the least squares line.
    static class 
    Calculate the y-intercept of the least squares line.
    static class 
    Calculate the slop of the least squares line.
    static class 
    The biggest of the data points and it's time stamp (the first one) is stored.
    static class 
    The smallest of the data points and it's time stamp (the first one) is stored.
    (package private) static final class 
    Store all the informations about a datasource point, for predictive and consistent sorting
    static class 
    Find the point at the n-th percentile.
    static class 
     
    static class 
    Calculate the standard deviation for the data point.
    static class 
    Calculate the sum of the data points.
    static final class 
    This class store both the value and the time stamp It will be used by graph rendering legend
  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final Variable.Value
     
  • Constructor Summary

    Constructors
    Constructor
    Description
     
  • Method Summary

    Modifier and Type
    Method
    Description
    (package private) void
    calculate(Source s, long start, long end)
    Used to calculate the needed value from a source, this method call the abstract method fill(long[], double[], long, long).
    protected abstract Variable.Value
    fill(long[] timestamps, double[] values, long start, long end)
    This method is call with the needed values, extracted from the datasource to do the calculation.
     

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Field Details

  • Constructor Details

    • Variable

      public Variable()
  • Method Details

    • calculate

      void calculate(Source s, long start, long end)
      Used to calculate the needed value from a source, this method call the abstract method fill(long[], double[], long, long).
      Parameters:
      s -
      start -
      end -
    • getValue

      public Variable.Value getValue()
    • fill

      protected abstract Variable.Value fill(long[] timestamps, double[] values, long start, long end)
      This method is call with the needed values, extracted from the datasource to do the calculation. Value is to be filled with both the double value and a possible timestamp, when it's used to find a specific point
      Parameters:
      timestamps - the timestamps for the value
      values - the actual values
      start - the start of the period
      end - the end of the period
      Returns:
      a filled Value object