net.sf.saxon.expr
Interface MappingFunction

All Known Implementing Classes:

Atomizer.AtomizingFunction, TupleSorter

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

java.lang.Object

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

Method Detail

map

public java.lang.Object 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) an Item if it maps to a single item, or (c) null if it maps to an empty sequence.

Throws:

XPathException