Package org.rrd4j.data

Class DataProcessor

java.lang.Object
org.rrd4j.data.DataProcessor
All Implemented Interfaces:
DataHolder
public class DataProcessor extends Object implements DataHolder

Class which should be used for all calculations based on the data fetched from RRD files. This class supports ordinary DEF datasources (defined in RRD files), CDEF datasources (RPN expressions evaluation), SDEF (static datasources - extension of Rrd4j) and PDEF (plottables, see Plottable for more information.

Typical class usage:

 final long t1 = ...
 final long t2 = ...
 DataProcessor dp = new DataProcessor(t1, t2);
 // DEF datasource
 dp.addDatasource("x", "demo.rrd", "some_source", "AVERAGE");
 // DEF datasource
 dp.addDatasource("y", "demo.rrd", "some_other_source", "AVERAGE");
 // CDEF datasource, z = (x + y) / 2
 dp.addDatasource("z", "x,y,+,2,/");
 // ACTION!
 dp.processData();
 // Dump calculated values
 System.out.println(dp.dump());

  • Field Details

    • DEFAULT_PIXEL_COUNT

      @Deprecated public static final int DEFAULT_PIXEL_COUNT
      Deprecated.
      Not used any more.
      See Also:

    • DEFAULT_PERCENTILE

      public static final double DEFAULT_PERCENTILE
      Constant DEFAULT_PERCENTILE=95.0
      See Also:

  • Constructor Details

    • DataProcessor

      public DataProcessor(long t1, long t2)
      Creates new DataProcessor object for the given time span. Ending timestamp may be set to zero. In that case, the class will try to find the optimal ending timestamp based on the last update time of RRD files processed with the processData() method.
      Parameters:
      t1 - Starting timestamp in seconds without milliseconds
      t2 - Ending timestamp in seconds without milliseconds

    • DataProcessor

      public DataProcessor(Date d1, Date d2)
      Creates new DataProcessor object for the given time span. Ending date may be set to null. In that case, the class will try to find optimal ending date based on the last update time of RRD files processed with the processData() method.
      Parameters:
      d1 - Starting date
      d2 - Ending date

    • DataProcessor

      public DataProcessor(Calendar gc1, Calendar gc2)
      Creates new DataProcessor object for the given time span. Ending date may be set to null. In that case, the class will try to find optimal ending date based on the last update time of RRD files processed with the processData() method. It use the time zone for starting calendar date.
      Parameters:
      gc1 - Starting Calendar date
      gc2 - Ending Calendar date

    • DataProcessor

      public DataProcessor(java.time.temporal.TemporalAmount d)
      Creates new DataProcessor object for the given time duration. The given duration will be substracted from current time.
      Parameters:
      d - duration to substract.

  • Method Details

    • isPoolUsed

      public boolean isPoolUsed()
      Returns boolean value representing RrdDbPool usage policy.
      Specified by:
      isPoolUsed in interface DataHolder
      Returns:
      true, if the pool will be used internally to fetch data from RRD files, false otherwise.

    • setPoolUsed

      public void setPoolUsed(boolean poolUsed)
      Sets the RrdDbPool usage policy.
      Specified by:
      setPoolUsed in interface DataHolder
      Parameters:
      poolUsed - true, if the pool should be used to fetch data from RRD files, false otherwise.

    • getPool

      public RrdDbPool getPool()
      Specified by:
      getPool in interface DataHolder

    • setPool

      public void setPool(RrdDbPool pool)
      Defines the RrdDbPool to use. If not defined, but {setPoolUsed(boolean) set to true, the default RrdDbPool.getInstance() will be used.
      Specified by:
      setPool in interface DataHolder
      Parameters:
      pool - an optional pool to use.

    • setPixelCount

      public void setPixelCount(int pixelCount)

      Sets the number of pixels (target graph width). This number is used only to calculate pixel coordinates for Rrd4j graphs (methods getValuesPerPixel(String) and getTimestampsPerPixel()), but has influence neither on datasource values calculated with the processData() method nor on aggregated values returned from getAggregates(String) and similar methods. In other words, aggregated values will not change once you decide to change the dimension of your graph.

      Parameters:
      pixelCount - The number of pixels. If you process RRD data in order to display it on the graph, this should be the width of your graph.

    • getPixelCount

      public int getPixelCount()
      Returns the number of pixels (target graph width). See setPixelCount(int) for more information.
      Returns:
      Target graph width

    • setStep

      public void setStep(long step)
      Once data are fetched, the step value will be used to generate values. If not defined, or set to 0, a optimal step will be calculated.
      Specified by:
      setStep in interface DataHolder
      Parameters:
      step - Default to 0.

    • getStep

      public long getStep()
      Returns the time step used for data processing. Initially, this method returns zero. Once processData() is finished, the method will return the time stamp interval.
      Specified by:
      getStep in interface DataHolder
      Returns:
      Step used for data processing.

    • getFetchRequestResolution

      public long getFetchRequestResolution()
      Returns desired RRD archive step (resolution) in seconds to be used while fetching data from RRD files. In other words, this value will used as the last parameter of RrdDb.createFetchRequest() method when this method is called internally by this DataProcessor.
      Returns:
      Desired archive step (fetch resolution) in seconds.

    • setFetchRequestResolution

      public void setFetchRequestResolution(long fetchRequestResolution)
      Sets desired RRD archive step in seconds to be used internally while fetching data from RRD files. In other words, this value will used as the last parameter of RrdDb.createFetchRequest() method when this method is called internally by this DataProcessor. If this method is never called, fetch request resolution defaults to 1 (smallest possible archive step will be chosen automatically).
      Parameters:
      fetchRequestResolution - Desired archive step (fetch resolution) in seconds.

    • getTimeZone

      public TimeZone getTimeZone()
      Specified by:
      getTimeZone in interface DataHolder

    • setTimeZone

      public void setTimeZone(TimeZone tz)
      Description copied from interface: DataHolder
      Set the time zone used for the legend.
      Specified by:
      setTimeZone in interface DataHolder
      Parameters:
      tz - the time zone to set

    • getEndingTimestamp

      public long getEndingTimestamp()
      Deprecated.
      Uses getEndTime() instead.
      Returns ending timestamp. Basically, this value is equal to the ending timestamp specified in the constructor. However, if the ending timestamps was zero, it will be replaced with the real timestamp when the processData() method returns. The real value will be calculated from the last update times of processed RRD files.
      Returns:
      Ending timestamp in seconds

    • getTimestamps

      public long[] getTimestamps()
      Returns consolidated timestamps created with the processData() method.
      Returns:
      array of timestamps in seconds

    • getValues

      public double[] getValues(String sourceName)
      Returns calculated values for a single datasource. Corresponding timestamps can be obtained from the getTimestamps() method.
      Parameters:
      sourceName - Datasource name
      Returns:
      an array of datasource values
      Throws:
      IllegalArgumentException - Thrown if invalid datasource name is specified, or if datasource values are not yet calculated (method processData() was not called)

    • getAggregate

      @Deprecated public double getAggregate(String sourceName, ConsolFun consolFun)
      Deprecated.
      Use Variable based method instead.
      Returns single aggregated value for a single datasource.
      Parameters:
      sourceName - Datasource name
      consolFun - Consolidation function to be applied to fetched datasource values. Valid consolidation functions are MIN, MAX, LAST, FIRST, AVERAGE and TOTAL (these string constants are conveniently defined in the ConsolFun class)
      Returns:
      a aggregate value as a double calculated from the source.
      Throws:
      IllegalArgumentException - Thrown if invalid datasource name is specified, or if datasource values are not yet calculated (method processData() was not called)

    • getAggregates

      @Deprecated public Aggregates getAggregates(String sourceName)
      Deprecated.
      Use Variable based method instead.
      Returns all (MIN, MAX, LAST, FIRST, AVERAGE and TOTAL) aggregated values for a single datasource.
      Parameters:
      sourceName - Datasource name
      Returns:
      Object containing all aggregated values
      Throws:
      IllegalArgumentException - Thrown if invalid datasource name is specified, or if datasource values are not yet calculated (method processData() was not called)

    • getVariable

      public Variable.Value getVariable(String sourceName)
      Extract the variable value from an already define Variable datasource (a VDEF)
      Parameters:
      sourceName - Datasource name
      Returns:
      A combined time and value extracted calculated from the datasource

    • getVariable

      public Variable.Value getVariable(String sourceName, Variable var)
      Returns single aggregated value for a single datasource.
      Parameters:
      sourceName - Datasource name
      var - variable that will generate value
      Returns:
      A combined time and value extracted calculated from the datasource

    • get95Percentile

      @Deprecated public double get95Percentile(String sourceName)
      Deprecated.
      Use Variable based method instead.
      This method is just an alias for getPercentile(String) method. Used by ISPs which charge for bandwidth utilization on a "95th percentile" basis.

      The 95th percentile is the highest source value left when the top 5% of a numerically sorted set of source data is discarded. It is used as a measure of the peak value used when one discounts a fair amount for transitory spikes. This makes it markedly different from the average.

      Read more about this topic at Rednet or Bytemark.

      Parameters:
      sourceName - Datasource name
      Returns:
      95th percentile of fetched source values

    • getPercentile

      @Deprecated public double getPercentile(String sourceName)
      Deprecated.
      Use Variable based method instead.
      Used by ISPs which charge for bandwidth utilization on a "95th percentile" basis.

      The 95th percentile is the highest source value left when the top 5% of a numerically sorted set of source data is discarded. It is used as a measure of the peak value used when one discounts a fair amount for transitory spikes. This makes it markedly different from the average.

      Read more about this topic at Rednet or Bytemark.

      Parameters:
      sourceName - Datasource name
      Returns:
      95th percentile of fetched source values

    • getPercentile

      @Deprecated public double getPercentile(String sourceName, double percentile)
      Deprecated.
      Use Variable based method instead.
      The same as getPercentile(String) but with a possibility to define custom percentile boundary (different from 95).
      Parameters:
      sourceName - Datasource name.
      percentile - Boundary percentile. Value of 95 (%) is suitable in most cases, but you are free to provide your own percentile boundary between zero and 100.
      Returns:
      Requested percentile of fetched source values

    • getSourceNames

      public String[] getSourceNames()
      Returns array of datasource names defined in this DataProcessor.
      Returns:
      array of datasource names

    • getValues

      public double[][] getValues()
      Returns an array of all datasource values for all datasources. Each row in this two-dimensional array represents an array of calculated values for a single datasource. The order of rows is the same as the order in which datasources were added to this DataProcessor object.
      Returns:
      All datasource values for all datasources. The first index is the index of the datasource, the second index is the index of the datasource value. The number of datasource values is equal to the number of timestamps returned with getTimestamps() method.
      Throws:
      IllegalArgumentException - Thrown if invalid datasource name is specified, or if datasource values are not yet calculated (method processData() was not called)

    • getSource

      Source getSource(String sourceName)

    • addDatasource

      @Deprecated public void addDatasource(String name, Plottable plottable)
      Deprecated.
      Uses datasource(String, IPlottable) instead
      Adds a custom, plottable datasource (PDEF). The datapoints should be made available by a class extending Plottable class.
      Parameters:
      name - source name.
      plottable - class that extends Plottable class and is suited for graphing.

    • datasource

      public void datasource(String name, IPlottable plottable)
      Adds a custom, plottable datasource (PDEF). The datapoints should be made available by a class extending Plottable class.
      Specified by:
      datasource in interface DataHolder
      Parameters:
      name - source name.
      plottable - class that extends Plottable class and is suited for graphing.
      Since:
      3.7

    • addDatasource

      @Deprecated public void addDatasource(String name, String rpnExpression)
      Deprecated.
      Uses datasource(String, String) instead

      Adds complex source (CDEF). Complex sources are evaluated using the supplied RPN expression.

      Complex source name can be used:
      • To specify sources for line, area and stack plots.
      • To define other complex sources.
      The supported RPN functions, operators and constants are detailed at RRD4J's wiki.

      Rrd4j does not force you to specify at least one simple source name as RRDTool.

      For more details on RPN see RRDTool's rrdgraph man page.

      Parameters:
      name - source name.
      rpnExpression - RPN expression containing comma delimited simple and complex source names, RPN constants, functions and operators.

    • datasource

      public void datasource(String name, String rpnExpression)

      Adds complex source (CDEF). Complex sources are evaluated using the supplied RPN expression.

      Complex source name can be used:
      • To specify sources for line, area and stack plots.
      • To define other complex sources.
      The supported RPN functions, operators and constants are detailed at RRD4J's wiki.

      Rrd4j does not force you to specify at least one simple source name as RRDTool.

      For more details on RPN see RRDTool's rrdgraph man page.

      Specified by:
      datasource in interface DataHolder
      Parameters:
      name - source name.
      rpnExpression - RPN expression containing comma delimited simple and complex source names, RPN constants, functions and operators.
      Since:
      3.7

    • addDatasource

      @Deprecated public void addDatasource(String name, String defName, ConsolFun consolFun)
      Deprecated.
      Use Variable based method instead.
      Adds static source (SDEF). Static sources are the result of a consolidation function applied to any other source that has been defined previously.
      Parameters:
      name - source name.
      defName - Name of the datasource to calculate the value from.
      consolFun - Consolidation function to use for value calculation

    • addDatasource

      @Deprecated public void addDatasource(String name, String sourceName, double percentile)
      Deprecated.
      Use Variable based method instead.
      Creates a datasource that performs a percentile calculation on an another named datasource to yield a single value. Requires that the other datasource has already been defined; otherwise, it'll end up with no data
      Parameters:
      name - - the new virtual datasource name
      sourceName - - the datasource from which to extract the percentile. Must be a previously defined virtual datasource
      percentile - - the percentile to extract from the source datasource

    • addDatasource

      @Deprecated public void addDatasource(String name, String defName, Variable var)
      Deprecated.
      Uses datasource(String, String, Variable) instead.
      Creates a datasource that performs a variable calculation on an another named datasource to yield a single combined timestamp/value. Requires that the other datasource has already been defined; otherwise, it'll end up with no data
      Parameters:
      name - - the new virtual datasource name
      defName - - the datasource from which to extract the percentile. Must be a previously defined virtual datasource
      var - - a new instance of a Variable used to do the calculation

    • datasource

      public void datasource(String name, String defName, Variable var)
      Creates a datasource that performs a variable calculation on an another named datasource to yield a single combined timestamp/value. Requires that the other datasource has already been defined; otherwise, it'll end up with no data
      Specified by:
      datasource in interface DataHolder
      Parameters:
      name - - the new virtual datasource name
      defName - - the datasource from which to extract the percentile. Must be a previously defined virtual datasource
      var - - a new instance of a Variable used to do the calculation
      Since:
      3.7

    • addDatasource

      @Deprecated public void addDatasource(String name, String file, String dsName, ConsolFun consolFunc)
      Deprecated.
      Uses datasource(String, String, String, ConsolFun) instead.

      Adds simple datasource (DEF). Simple source name can be used:

      • To specify sources for line, area and stack plots.
      • To define complex sources
      Parameters:
      name - source name.
      file - Path to RRD file.
      dsName - Datasource name defined in the RRD file.
      consolFunc - Consolidation function that will be used to extract data from the RRD

    • datasource

      public void datasource(String name, String file, String dsName, ConsolFun consolFunc)

      Adds simple datasource (DEF). Simple source name can be used:

      • To specify sources for line, area and stack plots.
      • To define complex sources
      Specified by:
      datasource in interface DataHolder
      Parameters:
      name - source name.
      file - Path to RRD file.
      dsName - Datasource name defined in the RRD file.
      consolFunc - Consolidation function that will be used to extract data from the RRD
      Since:
      3.7

    • datasource

      public void datasource(String name, URI rrdUri, String dsName, ConsolFun consolFunc)

      Adds simple datasource (DEF). Simple source name can be used:

      • To specify sources for line, area and stack plots.
      • To define complex sources
      Specified by:
      datasource in interface DataHolder
      Parameters:
      name - source name.
      rrdUri - URI to RRD file.
      dsName - Datasource name defined in the RRD file.
      consolFunc - Consolidation function that will be used to extract data from the RRD
      Since:
      3.7

    • addDatasource

      @Deprecated public void addDatasource(String name, String file, String dsName, ConsolFun consolFunc, String backend)
      Deprecated.
      uses datasource(String, String, String, ConsolFun, RrdBackendFactory) instead

      Adds simple source (DEF). Source name can be used:

      • To specify sources for line, area and stack plots.
      • To define complex sources
      Parameters:
      name - Source name.
      file - Path to RRD file.
      dsName - Data source name defined in the RRD file.
      consolFunc - Consolidation function that will be used to extract data from the RRD file ("AVERAGE", "MIN", "MAX" or "LAST" - these string constants are conveniently defined in the ConsolFun class).
      backend - Name of the RrdBackendFactory that should be used for this RrdDb.

    • addDatasource

      @Deprecated public void addDatasource(String name, String file, String dsName, ConsolFun consolFunc, RrdBackendFactory backend)
      Deprecated.
      uses datasource(String, String, String, ConsolFun, RrdBackendFactory) instead

      Adds simple source (DEF). Source name can be used:

      • To specify sources for line, area and stack plots.
      • To define complex sources
      Parameters:
      name - Source name.
      file - Path to RRD file.
      dsName - Data source name defined in the RRD file.
      consolFunc - Consolidation function that will be used to extract data from the RRD file ("AVERAGE", "MIN", "MAX" or "LAST" - these string constants are conveniently defined in the ConsolFun class).
      backend - Name of the RrdBackendFactory that should be used for this RrdDb.

    • datasource

      public void datasource(String name, String file, String dsName, ConsolFun consolFunc, RrdBackendFactory backend)

      Adds simple source (DEF). Source name can be used:

      • To specify sources for line, area and stack plots.
      • To define complex sources
      Specified by:
      datasource in interface DataHolder
      Parameters:
      name - Source name.
      file - Path to RRD file.
      dsName - Data source name defined in the RRD file.
      consolFunc - Consolidation function that will be used to extract data from the RRD file ("AVERAGE", "MIN", "MAX" or "LAST" - these string constants are conveniently defined in the ConsolFun class).
      backend - Name of the RrdBackendFactory that should be used for this RrdDb.
      Since:
      3.7

    • datasource

      public void datasource(String name, URI uri, String dsName, ConsolFun consolFunc, RrdBackendFactory backend)

      Adds simple source (DEF). Source name can be used:

      • To specify sources for line, area and stack plots.
      • To define complex sources
      Specified by:
      datasource in interface DataHolder
      Parameters:
      name - Source name.
      uri - URI to RRD file.
      dsName - Data source name defined in the RRD file.
      consolFunc - Consolidation function that will be used to extract data from the RRD file ("AVERAGE", "MIN", "MAX" or "LAST" - these string constants are conveniently defined in the ConsolFun class).
      backend - Name of the RrdBackendFactory that should be used for this RrdDb.
      Since:
      3.7

    • addDatasource

      @Deprecated public void addDatasource(String name, FetchData fetchData)
      Deprecated.
      Uses datasource(String, FetchData) instead.
      Adds DEF datasource with datasource values already available in the FetchData object. This method is used internally by Rrd4j and probably has no purpose outside of it.
      Parameters:
      name - Source name.
      fetchData - Fetched data containing values for the given source name.

    • datasource

      public void datasource(String name, FetchData fetchData)
      Adds DEF datasource with datasource values already available in the FetchData object. This method is used internally by Rrd4j and probably has no purpose outside of it.
      Specified by:
      datasource in interface DataHolder
      Parameters:
      name - Source name.
      fetchData - Fetched data containing values for the given source name.
      Since:
      3.7

    • addDatasource

      @Deprecated public void addDatasource(String name, String dsName, FetchData fetchData)
      Deprecated.
      Uses datasource(String, String, FetchData) instead.
      Adds DEF datasource with datasource values already available in the FetchData object. This method is used internally by Rrd4j and probably has no purpose outside of it. The values will be extracted from dsName in fetchData.
      Parameters:
      name - Source name.
      dsName - Source name in the fetch data.
      fetchData - Fetched data containing values for the given source name.

    • datasource

      public void datasource(String name, String dsName, FetchData fetchData)
      Adds DEF datasource with datasource values already available in the FetchData object. This method is used internally by Rrd4j and probably has no purpose outside of it. The values will be extracted from dsName in fetchData.
      Specified by:
      datasource in interface DataHolder
      Parameters:
      name - Source name.
      dsName - Source name in the fetch data.
      fetchData - Fetched data containing values for the given source name.
      Since:
      3.7

    • processData

      public void processData() throws IOException
      Method that should be called once all datasources are defined. Data will be fetched from RRD files, RPN expressions will be calculated, etc.
      Throws:
      IOException - Thrown in case of I/O error (while fetching data from RRD files)

    • getValuesPerPixel

      public double[] getValuesPerPixel(String sourceName, int pixelCount)
      Method used to calculate datasource values which should be presented on the graph based on the desired graph width. Each value returned represents a single pixel on the graph. Corresponding timestamp can be found in the array returned from getTimestampsPerPixel() method.
      Parameters:
      sourceName - Datasource name
      pixelCount - Graph width
      Returns:
      Per-pixel datasource values
      Throws:
      IllegalArgumentException - Thrown if datasource values are not yet calculated (method processData() was not called)

    • getValuesPerPixel

      public double[] getValuesPerPixel(String sourceName)
      Method used to calculate datasource values which should be presented on the graph based on the graph width set with a setPixelCount(int) method call. Each value returned represents a single pixel on the graph. Corresponding timestamp can be found in the array returned from getTimestampsPerPixel() method.
      Parameters:
      sourceName - Datasource name
      Returns:
      Per-pixel datasource values
      Throws:
      IllegalArgumentException - Thrown if datasource values are not yet calculated (method processData() was not called)

    • getTimestampsPerPixel

      public long[] getTimestampsPerPixel(int pixelCount)
      Calculates timestamps which correspond to individual pixels on the graph. It also set the timestampsPerPixel value.
      Parameters:
      pixelCount - Graph width
      Returns:
      Array of timestamps

    • getTimestampsPerPixel

      public long[] getTimestampsPerPixel()
      Calculates timestamps which correspond to individual pixels on the graph based on the graph width set with a setPixelCount(int) method call.
      Returns:
      Array of timestamps

    • dump

      public String dump()
      Dumps timestamps and values of all datasources in a tabular form. Very useful for debugging.
      Returns:
      Dumped object content.

    • getLastRrdArchiveUpdateTime

      public long getLastRrdArchiveUpdateTime()
      Returns time when last RRD archive was updated (all RRD files are considered).
      Returns:
      Last archive update time for all RRD files in this DataProcessor

    • setEndTime

      public void setEndTime(long time)
      Description copied from interface: DataHolder
      Sets the time when the graph should end. Time in seconds since epoch (1970-01-01) is required. Negative numbers are relative to the current time.
      Specified by:
      setEndTime in interface DataHolder
      Parameters:
      time - Ending time for the graph in seconds since epoch
      Since:
      3.7

    • getEndTime

      public long getEndTime()
      Description copied from interface: DataHolder
      Returns ending timestamp.
      Specified by:
      getEndTime in interface DataHolder
      Returns:
      Ending timestamp in seconds
      Since:
      3.7

    • setStartTime

      public void setStartTime(long time)
      Description copied from interface: DataHolder
      Sets the time when the graph should start. Time in seconds since epoch (1970-01-01) is required. Negative numbers are relative to the current time.
      Specified by:
      setStartTime in interface DataHolder
      Parameters:
      time - Starting time for the graph in seconds since epoch

    • getStartTime

      public long getStartTime()
      Description copied from interface: DataHolder
      Returns starting timestamp.
      Specified by:
      getStartTime in interface DataHolder
      Returns:
      Starting timestamp in seconds
      Since:
      3.7

    • setTimeSpan

      public void setTimeSpan(long startTime, long endTime)
      Description copied from interface: DataHolder
      Sets starting and ending time for the for the graph. Timestamps in seconds since epoch are required. Negative numbers are relative to the current time.
      Specified by:
      setTimeSpan in interface DataHolder
      Parameters:
      startTime - Starting time in seconds since epoch
      endTime - Ending time in seconds since epoch
      Since:
      3.7