This package provides utility routines for sorting and grouping.
Specifically, it contains a QuickSort implementation,
AtomicComparer objects that handle character and numeric comparisons, together
with the important
DocumentOrderIterator which iterates over a set of nodes in document
The package also
contains the classes to support the implementation of the XSLT 2.0 instruction
xsl:for-each-group, and some utilities for maintaining sets and maps whose keys
are unboxed integer values.