Package org.HdrHistogram

Class ShortCountsHistogram

    • Constructor Detail

      • 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 Detail

      • 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