java.lang.Object
org.rrd4j.graph.Source
org.rrd4j.graph.Def
class Defextends Source
Represents a data definition (DEF) in RRD graphs. A DEF defines a data source by specifying an RRD file, data source name, and consolidation function. This is the primary way to import data from RRD files into graphs.

  • Field Details

    • rrdUri

      private final URI rrdUri
      The RRD file the definition reads.

    • dsName

      private final String dsName
      The data source to read.

    • backend

      private final RrdBackendFactory backend
      Backend used to open the file.

    • consolFun

      private final ConsolFun consolFun
      Consolidation function to read with.

  • Constructor Details

    • Def

      Def(String name, URI rrdUri, String dsName, ConsolFun consolFun, RrdBackendFactory backend)
      Creates a DEF naming the RRD, datasource, consolidation function and backend to read from, which requestData(DataProcessor) hands to a data processor as a source to fetch.
      Parameters:
      name - DEF name, used to identify this series within the graph
      rrdUri - location of the RRD holding the datasource
      dsName - name of the datasource to read within that RRD
      consolFun - consolidation function (CF) the archive values were produced with
      backend - factory that opens the RRD when the definition is fetched

  • Method Details

    • requestData

      void requestData(DataProcessor dproc)
      Request data
      Specified by:
      requestData in class Source
      Parameters:
      dproc - the data processor to receive the data