| java.lang.Object
 gnu.lists.FilterConsumer
gnu.xquery.util.OrderedTuples
| OrderedTuples | | public class OrderedTuples extends FilterConsumer (Code) | | Helper class used in conjunction with
OrderedMap .
It has the tuples from the
for and
let -clauses,
as filtered by the
where -clause.
The tuples are sorted using a linked-list version of merge sort.
The sequence of n tuples for m variables is represented using
an array of length n where each element is an array of length m.
A possible future optimization would be to instead use m
different arrays of of length n. The advantage is that each
of the M arrays could have the "correct" type for each variable,
and so we avoid casts or boxing/unboxing.
|
| Field Summary | |
| Procedure | body
The return clause, encoded as a procedure on a tuple. | | Object[] | comps
The compator functions. | | int | first
| | int | n
The number of tuples. | | int[] | next
Used to chain the tuples after sorting.
I.e. | | Object[] | tuples
The sequence of tuples, in input (unsorted) order. |
| body | | Procedure body(Code) | | The return clause, encoded as a procedure on a tuple.
|
| comps | | Object[] comps(Code) | | The compator functions.
If there are k comparator, the array's length is 3*k.
comps[3*i] is the i'th comparison function
(represented as a procedure on a tuple);
comps[3*i+1] is the i'th set of flags encoded as a string;
and comps[3*i+2] is the i'th collator
(either null or a NamedCollator).
|
| n | | int n(Code) | | The number of tuples.
|
| next | | int[] next(Code) | | Used to chain the tuples after sorting.
I.e. if the i'th tuple (is sort order) is tuples[k],
then the (i+1)'the sorted tuple is tuples[next[k]].
The end of the list is indicated by -1.
|
| tuples | | Object[] tuples(Code) | | The sequence of tuples, in input (unsorted) order.
|
| OrderedTuples | | OrderedTuples()(Code) | | |
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