Package net.sf.saxon.expr

Interface MappingFunction

All Known Implementing Classes:
ForExpression.MappingAction, SequenceMapper
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 MappingFunction
MappingFunction is an interface that must be satisfied by an object passed to a MappingIterator. It represents an object which, given an Item, can return a SequenceIterator that delivers a sequence of zero or more Items.

It maps an item of class F to a sequence of items of class T, returned as an iterator.

NOTE: Java allows a lambda expression to be used where an ItemMappingFunction is needed, but C# does not (it's not possible in C# to have a class implementing a delegate). So if a delegate is wanted, use SequenceMapper.

  • Method Summary

    Modifier and Type
    Method
    Description
    SequenceIterator
    map(Item item)
    Map one item to a sequence.

  • Method Details

    • map

      SequenceIterator map(Item item) throws XPathException
      Map one item to a sequence.
      Parameters:
      item - The item to be mapped.
      Returns:
      one of the following: (a) a SequenceIterator over the sequence of items that the supplied input item maps to, or (b) null if it maps to an empty sequence.
      Throws:
      XPathException - if a dynamic error occurs