Package nz.org.riskscape.engine.function

Interface UntypedFunction

All Superinterfaces:
AutoCloseable
All Known Subinterfaces:
IdentifiedFunction, RiskscapeFunction
All Known Implementing Classes:
AddAggregationFunction, AggregationFunctionAdapter, BinaryFunction, BinaryOperatorFunction, BinaryPredicateFunction, ConstantFunction, IdentifiedFunction.Wrapping, JavaFunction, MetadataBasedFunction, NullSafeFunction, RealizableFunction.MetadataIdentifiedRealizableFunction, UnaryFunction
Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.
@FunctionalInterface public interface UntypedFunction extends AutoCloseable

A minimal RiskscapeFunction interface, which exists for two reasons: 1) store a reference to a first-class function in a tuple 2) a minimal functional interface for use with creating minimal riskscape functions without having to implement RiskscapeFunction.

When an UntypedFunction is using for storing a reference to a higher order/first class function as part of a RiskScape pipeline or expression, we don't want to carry around all the extra type metadata with each instance of the function, as this is going to be static, and just means needlessly holding on to more bytes. Hence this interface exists, allowing implementations to be as light-touch on memory as possible.

When stored in a tuple, an UntypedFunction is represented with a FunctionType type, which stores the signature for all instances of the function that can be in a tuple of that type.

  • Method Summary

    Modifier and Type
    Method
    Description
    Object
    call(List<Object> args)
    Execute the function with the given arguments.
    default void
    close()
    Clean up any resources that were allocated with this function.

  • Method Details

    • call

      Object call(List<Object> args)

      Execute the function with the given arguments.

      Parameters:
      args - list of arguments to the function that should conform to the types in ArgumentList.getArgumentTypes()

    • close

      default void close()

      Clean up any resources that were allocated with this function. This can include large objects, so that any memory used can be reclaimed.

      See Realized for more information on the life-cycle of executable pipeline objects.

      Note that there is no standard mechanism for cleaning up resources allocated to functions that realize lambda expressions - the closing of any RealizedExpressions or related objects must be done by the function when it's closed. This is probably something that should be addressed once some standard patterns have been established for the implementation of lambda-accepting functions.

      Specified by:
      close in interface AutoCloseable