Package org.HdrHistogram

Class ShortCountsHistogram

java.lang.Object
org.HdrHistogram.EncodableHistogram
org.HdrHistogram.AbstractHistogram
org.HdrHistogram.ShortCountsHistogram
All Implemented Interfaces:
Serializable, ValueRecorder
public class ShortCountsHistogram extends AbstractHistogram

A High Dynamic Range (HDR) Histogram using a short count type

See package description for org.HdrHistogram for details.

See Also:

  • Constructor Details

    • ShortCountsHistogram

      public ShortCountsHistogram(int numberOfSignificantValueDigits)
      Construct an auto-resizing ShortCountsHistogram with a lowest discernible value of 1 and an auto-adjusting highestTrackableValue. Can auto-resize up to track values up to (Long.MAX_VALUE / 2).
      Parameters:
      numberOfSignificantValueDigits - Specifies the precision to use. This is the number of significant decimal digits to which the histogram will maintain value resolution and separation. Must be a non-negative integer between 0 and 5.

    • ShortCountsHistogram

      public ShortCountsHistogram(long highestTrackableValue, int numberOfSignificantValueDigits)
      Construct a ShortCountsHistogram given the Highest value to be tracked and a number of significant decimal digits. The histogram will be constructed to implicitly track (distinguish from 0) values as low as 1.
      Parameters:
      highestTrackableValue - The highest value to be tracked by the histogram. Must be a positive integer that is >= 2.
      numberOfSignificantValueDigits - Specifies the precision to use. This is the number of significant decimal digits to which the histogram will maintain value resolution and separation. Must be a non-negative integer between 0 and 5.

    • ShortCountsHistogram

      public ShortCountsHistogram(long lowestDiscernibleValue, long highestTrackableValue, int numberOfSignificantValueDigits)
      Construct a ShortCountsHistogram given the Lowest and Highest values to be tracked and a number of significant decimal digits. Providing a lowestDiscernibleValue is useful is situations where the units used for the histogram's values are much smaller that the minimal accuracy required. E.g. when tracking time values stated in nanosecond units, where the minimal accuracy required is a microsecond, the proper value for lowestDiscernibleValue would be 1000.
      Parameters:
      lowestDiscernibleValue - The lowest value that can be tracked (distinguished from 0) by the histogram. Must be a positive integer that is >= 1. May be internally rounded down to nearest power of 2.
      highestTrackableValue - The highest value to be tracked by the histogram. Must be a positive integer that is >= (2 * lowestDiscernibleValue).
      numberOfSignificantValueDigits - Specifies the precision to use. This is the number of significant decimal digits to which the histogram will maintain value resolution and separation. Must be a non-negative integer between 0 and 5.

    • ShortCountsHistogram

      public ShortCountsHistogram(AbstractHistogram source)
      Construct a histogram with the same range settings as a given source histogram, duplicating the source's start/end timestamps (but NOT it's contents)
      Parameters:
      source - The source histogram to duplicate

  • Method Details

    • copy

      public ShortCountsHistogram copy()
      Description copied from class: AbstractHistogram
      Create a copy of this histogram, complete with data and everything.
      Specified by:
      copy in class AbstractHistogram
      Returns:
      A distinct copy of this histogram.

    • copyCorrectedForCoordinatedOmission

      public ShortCountsHistogram copyCorrectedForCoordinatedOmission(long expectedIntervalBetweenValueSamples)
      Description copied from class: AbstractHistogram
      Get a copy of this histogram, corrected for coordinated omission.

      To compensate for the loss of sampled values when a recorded value is larger than the expected interval between value samples, the new histogram will include an auto-generated additional series of decreasingly-smaller (down to the expectedIntervalBetweenValueSamples) value records for each count found in the current histogram that is larger than the expectedIntervalBetweenValueSamples. Note: This is a post-correction method, as opposed to the at-recording correction method provided by recordValueWithExpectedInterval. The two methods are mutually exclusive, and only one of the two should be be used on a given data set to correct for the same coordinated omission issue. by

      See notes in the description of the Histogram calls for an illustration of why this corrective behavior is important.

      Specified by:
      copyCorrectedForCoordinatedOmission in class AbstractHistogram
      Parameters:
      expectedIntervalBetweenValueSamples - If expectedIntervalBetweenValueSamples is larger than 0, add auto-generated value records as appropriate if value is larger than expectedIntervalBetweenValueSamples
      Returns:
      a copy of this histogram, corrected for coordinated omission.

    • getTotalCount

      public long getTotalCount()
      Description copied from class: AbstractHistogram
      Get the total count of all recorded values in the histogram
      Specified by:
      getTotalCount in class AbstractHistogram
      Returns:
      the total count of all recorded values in the histogram

    • decodeFromByteBuffer

      public static ShortCountsHistogram decodeFromByteBuffer(ByteBuffer buffer, long minBarForHighestTrackableValue)
      Construct a new histogram by decoding it from a ByteBuffer.
      Parameters:
      buffer - The buffer to decode from
      minBarForHighestTrackableValue - Force highestTrackableValue to be set at least this high
      Returns:
      The newly constructed histogram

    • decodeFromCompressedByteBuffer

      public static ShortCountsHistogram decodeFromCompressedByteBuffer(ByteBuffer buffer, long minBarForHighestTrackableValue) throws DataFormatException
      Construct a new histogram by decoding it from a compressed form in a ByteBuffer.
      Parameters:
      buffer - The buffer to decode from
      minBarForHighestTrackableValue - Force highestTrackableValue to be set at least this high
      Returns:
      The newly constructed histogram
      Throws:
      DataFormatException - on error parsing/decompressing the buffer

    • fromString

      public static ShortCountsHistogram fromString(String base64CompressedHistogramString) throws DataFormatException
      Construct a new ShortCountsHistogram by decoding it from a String containing a base64 encoded compressed histogram representation.
      Parameters:
      base64CompressedHistogramString - A string containing a base64 encoding of a compressed histogram
      Returns:
      A ShortCountsHistogram decoded from the string
      Throws:
      DataFormatException - on error parsing/decompressing the input