Package org.jgroups.util

Class Average

  • All Implemented Interfaces:
    Streamable
    Direct Known Subclasses:
    AverageMinMax
    public class Average
extends java.lang.Object
implements Streamable
    Maintains an approximation of an average of positive (>= 0) values in a window and adding new values at random indices.
    This class is lock-less, at the expense of incorrect reads and writes (by multiple threads), but the noise of these errors should be neglectable. Note that a bigger capacity (window size) reduces this noise.
    Since:
    3.4, 5.4
    Author:
    Bela Ban

    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected boolean all_filled  
      protected static int DEFAULT_CAPACITY  
      protected long[] samples  
      protected java.util.concurrent.TimeUnit unit  

    • Constructor Summary

      Constructors 
      Constructor Description
      Average()  
      Average​(int capacity)  

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      <T extends Average>
      T      		 add​(long num)  
      double average()
      Returns the average of all valid samples divided by the number of valid samples
      int capacity()  
      void clear()  
      int count()
      Returns the number of valid samples (>= 0)
      double getAverage()  
      boolean isEmpty()
      Returns true if there are no valid samples (>= 0), false otherwise
      <T extends Average>
      T      		 merge​(T other)
      Merges this average with another one
      void readFrom​(java.io.DataInput in)
      Read the state of the current object (including superclasses) from instream Note that the input stream must not be closed
      java.lang.String toString()  
      java.lang.String toString​(java.util.concurrent.TimeUnit u)  
      long total()
      Returns the total of all valid (>= 0) values
      java.util.concurrent.TimeUnit unit()  
      <T extends Average>
      T      		 unit​(java.util.concurrent.TimeUnit u)  
      void writeTo​(java.io.DataOutput out)
      Write the entire state of the current object (including superclasses) to outstream.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

    • Field Detail

      • samples

        protected long[] samples

      • unit

        protected java.util.concurrent.TimeUnit unit

      • all_filled

        protected volatile boolean all_filled

    • Constructor Detail

      • Average

        public Average()

      • Average

        public Average​(int capacity)

    • Method Detail

      • capacity

        public int capacity()

      • unit

        public java.util.concurrent.TimeUnit unit()

      • unit

        public <T extends Average> T unit​(java.util.concurrent.TimeUnit u)

      • getAverage

        public double getAverage()

      • add

        public <T extends Average> T add​(long num)

      • merge

        public <T extends Average> T merge​(T other)
        Merges this average with another one

      • total

        public long total()
        Returns the total of all valid (>= 0) values

      • count

        public int count()
        Returns the number of valid samples (>= 0)

      • isEmpty

        public boolean isEmpty()
        Returns true if there are no valid samples (>= 0), false otherwise

      • average

        public double average()
        Returns the average of all valid samples divided by the number of valid samples

      • clear

        public void clear()

      • toString

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

      • toString

        public java.lang.String toString​(java.util.concurrent.TimeUnit u)

      • writeTo

        public void writeTo​(java.io.DataOutput out)
             throws java.io.IOException
        Description copied from interface: Streamable
        Write the entire state of the current object (including superclasses) to outstream. Note that the output stream must not be closed
        Specified by:
        writeTo in interface Streamable
        Throws:
        java.io.IOException

      • readFrom

        public void readFrom​(java.io.DataInput in)
              throws java.io.IOException
        Description copied from interface: Streamable
        Read the state of the current object (including superclasses) from instream Note that the input stream must not be closed
        Specified by:
        readFrom in interface Streamable
        Throws:
        java.io.IOException