Package org.apache.jena.sparql.expr.aggregate

Class AggregateRegistry

  • public class AggregateRegistry
extends java.lang.Object
    Registry of custom aggregates There is only a single global registry of aggregates - it affects parsing and parsing happens before Context or Execution makes sense.

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static AccumulatorFactory getAccumulatorFactory​(java.lang.String uri)
      Return the AccumulatorFactory for a registered custom aggregate.
      static Node getNoGroupValue​(java.lang.String uri)
      Return the registered "no groups" value
      static void init()  
      static boolean isRegistered​(java.lang.String uri)
      Is the URI registered as an aggregate function?
      static void register​(java.lang.String uri, AccumulatorFactory accFactory)
      Register a custom aggregate, with its associated factory for accumulators.
      static void register​(java.lang.String uri, AccumulatorFactory accFactory, Node noGroupValue)  
      static void unregister​(java.lang.String uri)
      Remove a registration.

      • Methods inherited from class java.lang.Object

        equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Constructor Detail

      • AggregateRegistry

        public AggregateRegistry()

    • Method Detail

      • init

        public static void init()

      • register

        public static void register​(java.lang.String uri,
                            AccumulatorFactory accFactory)
        Register a custom aggregate, with its associated factory for accumulators.

      • register

        public static void register​(java.lang.String uri,
                            AccumulatorFactory accFactory,
                            Node noGroupValue)

      • unregister

        public static void unregister​(java.lang.String uri)
        Remove a registration.

      • getAccumulatorFactory

        public static AccumulatorFactory getAccumulatorFactory​(java.lang.String uri)
        Return the AccumulatorFactory for a registered custom aggregate.

      • getNoGroupValue

        public static Node getNoGroupValue​(java.lang.String uri)
        Return the registered "no groups" value

      • isRegistered

        public static boolean isRegistered​(java.lang.String uri)
        Is the URI registered as an aggregate function?