net.sf.saxon.expr

Interface MappingFunction

Known Subinterfaces:
MappingIterator.StatefulMappingFunction
Known Implementing Classes:
Atomizer.AtomizingFunction, TupleSorter.TupleUnwrapper

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.

Method Summary

SequenceIterator
map(Item item)
Map one item to a sequence.

Method Details

map

public 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.