Package org.eclipse.jetty.util.statistic

Class SampleStatistic

  • @Deprecated(since="2021-05-27")
public class SampleStatistic
extends java.lang.Object
    Deprecated.
    The Eclipse Jetty and Apache Felix Http Jetty packages are no longer supported.

    Statistics on a sampled value.

    Provides max, total, mean, count, variance, and standard deviation of continuous sequence of samples.

    Calculates estimates of mean, variance, and standard deviation characteristics of a sample using a non synchronized approximation of the on-line algorithm presented in Donald Knuth's Art of Computer Programming, Volume 2, Semi numerical Algorithms, 3rd edition, page 232, Boston: Addison-Wesley. That cites a 1962 paper by B.P. Welford: Note on a Method for Calculating Corrected Sums of Squares and Products

    This algorithm is also described in Wikipedia in the section "Online algorithm": Algorithms for calculating variance.

    • Constructor Detail

      • SampleStatistic

        public SampleStatistic()
        Deprecated.

    • Method Detail

      • reset

        public void reset()
        Deprecated.
        Resets the statistics.

      • record

        public void record​(long sample)
        Deprecated.
        Records a sample value.
        Parameters:
        sample - the value to record.

      • set

        @Deprecated
public void set​(long sample)
        Deprecated.
        use record(long) instead
        Parameters:
        sample - the value to record.

      • getMax

        public long getMax()
        Deprecated.
        Returns:
        the max value of the recorded samples

      • getTotal

        public long getTotal()
        Deprecated.
        Returns:
        the sum of all the recorded samples

      • getCount

        public long getCount()
        Deprecated.
        Returns:
        the number of samples recorded

      • getMean

        public double getMean()
        Deprecated.
        Returns:
        the average value of the samples recorded, or zero if there are no samples

      • getVariance

        public double getVariance()
        Deprecated.
        Returns:
        the variance of the samples recorded, or zero if there are less than 2 samples

      • getStdDev

        public double getStdDev()
        Deprecated.
        Returns:
        the standard deviation of the samples recorded

      • toString

        public java.lang.String toString()
        Deprecated.
        Overrides:
        toString in class java.lang.Object