Interface Aggregate

  • All Superinterfaces:
    java.io.Serializable
    All Known Implementing Classes:
    AdHocPythonAggregate, AggregateInfo, AggregationMode

    public interface Aggregate
    extends java.io.Serializable
    This interface defines an aggregation function used by the history query system. Different types of history providers may support different Aggregate functions, and may define new types of aggregates. The name and description are for informational purposes, aggregates are only identified by their id (name and description should not be taken into account).

    The general implementation class is AggregateInfo. Common or "well known" aggregates are defined in the AggregationMode enum. The system works like this for historical reasons, previous to 7.7 only the AggregationMode aggregates were used. After, with the introduction of history providers as an extension point, new providers could define any aggregation function.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static int AD_HOC_PYTHON_ID
      Ad-hoc aggregates don't get registered anywhere, but can be sent to the history system.
      static int CUSTOM_RESERVED_ID
      All custom aggregates should be above this value
      static int PYTHON_LIB_ID  
    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      java.lang.String getDesc()
      A possible description for how the aggregate behaves.
      int getId()
      Returns the identifier for the aggregate.
      java.lang.String getName()
      A display name for the aggregate.
    • Field Detail

      • CUSTOM_RESERVED_ID

        static final int CUSTOM_RESERVED_ID
        All custom aggregates should be above this value
        See Also:
        Constant Field Values
      • AD_HOC_PYTHON_ID

        static final int AD_HOC_PYTHON_ID
        Ad-hoc aggregates don't get registered anywhere, but can be sent to the history system.
        See Also:
        Constant Field Values
    • Method Detail

      • getId

        int getId()
        Returns the identifier for the aggregate. This is the only true identifier for the aggregate, name and description should not be taken into account for equality.
      • getName

        java.lang.String getName()
        A display name for the aggregate.
      • getDesc

        java.lang.String getDesc()
        A possible description for how the aggregate behaves.