java.lang.Object
org.rrd4j.graph.Source
org.rrd4j.graph.VDef
class VDefextends Source
Represents a variable definition (VDEF) in RRD graphs. A VDEF defines a data source that computes values using variables like MIN, MAX, AVERAGE, etc.

  • Field Details

    • defName

      private final String defName
      Name other definitions use to refer to this one.

    • var

      private final Variable var
      The variable holding the defined value.

  • Constructor Details

    • VDef

      VDef(String name, String defName, Variable var)
      Creates a VDEF data source bound to the given name and computation
      Parameters:
      name - the name this data source is addressed by in the graph
      defName - the VDEF expression name identifying the computation to apply
      var - the variable the computation reduces to, such as MIN, MAX or AVERAGE

  • Method Details

    • requestData

      void requestData(DataProcessor dproc)
      Asks the processor to evaluate this VDEF for the given data source
      Specified by:
      requestData in class Source
      Parameters:
      dproc - the processor to pass the data source request to